draft-ietf-rddp-ddp-06.txt   draft-ietf-rddp-ddp-07.txt 
Remote Direct Data Placement Hemal Shah Remote Direct Data Placement Hemal Shah
Working Group Broadcom Corporation Working Group Broadcom Corporation
INTERNET-DRAFT James Pinkerton INTERNET-DRAFT James Pinkerton
Category: Standards Track Microsoft Corporation Category: Standards Track Microsoft Corporation
draft-ietf-rddp-ddp-06.txt Renato Recio draft-ietf-rddp-ddp-07.txt Renato Recio
IBM Corporation IBM Corporation
Paul Culley Paul Culley
Hewlett-Packard Company Hewlett-Packard Company
Expires: January, 2007 June, 2006 Expires: March, 2007 September, 2006
Direct Data Placement over Reliable Transports Direct Data Placement over Reliable Transports
Status of this Memo Status of this Memo
By submitting this Internet-Draft, each author represents that any By submitting this Internet-Draft, each author represents that any
applicable patent or other IPR claims of which he or she is aware applicable patent or other IPR claims of which he or she is aware
have been or will be disclosed, and any of which he or she becomes have been or will be disclosed, and any of which he or she becomes
aware will be disclosed, in accordance with Section 6 of BCP 79. aware will be disclosed, in accordance with Section 6 of BCP 79.
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http://www.ietf.org/shadow.html. http://www.ietf.org/shadow.html.
Abstract Abstract
The Direct Data Placement protocol provides information to Place the The Direct Data Placement protocol provides information to Place the
incoming data directly into an upper layer protocol's receive buffer incoming data directly into an upper layer protocol's receive buffer
without intermediate buffers. This removes excess CPU and memory without intermediate buffers. This removes excess CPU and memory
utilization associated with transferring data through the utilization associated with transferring data through the
intermediate buffers. intermediate buffers.
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Table of Contents Table of Contents
Status of this Memo...............................................1 Status of this Memo ....................................... 1
Abstract..........................................................1 Abstract................................................. 1
1 Introduction................................................4 1 Introduction......................................... 4
1.1 Architectural Goals.........................................4 1.1 Architectural Goals................................... 4
1.2 Protocol Overview...........................................5 1.2 Protocol Overview .................................... 5
1.3 DDP Layering................................................6 1.3 DDP Layering......................................... 6
2 Glossary....................................................9 2 Glossary............................................ 9
2.1 General.....................................................9 2.1 General............................................. 9
2.2 LLP........................................................10 2.2 LLP.................................................10
2.3 Direct Data Placement (DDP)................................11 2.3 Direct Data Placement (DDP)............................11
3 Reliable Delivery LLP Requirements.........................13 3 Reliable Delivery LLP Requirements......................13
4 Header Format..............................................15 4 Header Format........................................15
4.1 DDP Control Field..........................................15 4.1 DDP Control Field ....................................15
4.2 DDP Tagged Buffer Model Header.............................16 4.2 DDP Tagged Buffer Model Header.........................16
4.3 DDP Untagged Buffer Model Header...........................17 4.3 DDP Untagged Buffer Model Header .......................17
4.4 DDP Segment Format.........................................18 4.4 DDP Segment Format....................................18
5 Data Transfer..............................................19 5 Data Transfer........................................19
5.1 DDP Tagged or Untagged Buffer Models.......................19 5.1 DDP Tagged or Untagged Buffer Models....................19
5.1.1 Tagged Buffer Model.......................................19 5.1.1 Tagged Buffer Model.................................19
5.1.2 Untagged Buffer Model.....................................19 5.1.2 Untagged Buffer Model................................19
5.2 Segmentation and Reassembly of a DDP Message...............19 5.2 Segmentation and Reassembly of a DDP Message.............19
5.3 Ordering Among DDP Messages................................21 5.3 Ordering Among DDP Messages............................21
5.4 DDP Message Completion & Delivery..........................22 5.4 DDP Message Completion & Delivery.......................22
6 DDP Stream Setup & Teardown................................23 6 DDP Stream Setup & Teardown............................23
6.1 DDP Stream Setup...........................................23 6.1 DDP Stream Setup.....................................23
6.2 DDP Stream Teardown........................................23 6.2 DDP Stream Teardown...................................23
6.2.1 DDP Graceful Teardown.....................................23 6.2.1 DDP Graceful Teardown................................23
6.2.2 DDP Abortive Teardown.....................................24 6.2.2 DDP Abortive Teardown................................24
7 Error Semantics............................................25 7 Error Semantics......................................25
7.1 Errors detected at the Data Sink...........................25 7.1 Errors detected at the Data Sink .......................25
7.2 DDP Error Numbers..........................................26 7.2 DDP Error Numbers ....................................26
8 Security Considerations....................................27 8 Security Considerations...............................27
8.1 Protocol-specific Security Considerations..................27 8.1 Protocol-specific Security Considerations................27
8.2 Association of an STag and a DDP Stream....................27 8.2 Association of an STag and a DDP Stream.................27
8.3 Security Requirements......................................28 8.3 Security Requirements.................................28
8.3.1 RNIC Requirements.........................................29 8.3.1 RNIC Requirements...................................29
8.3.2 Privileged Resources Manager Requirement..................29 8.3.2 Privileged Resources Manager Requirement...............30
8.4 Security Services for DDP..................................30 8.4 Security Services for DDP..............................30
8.4.1 Available Security Services...............................30 8.4.1 Available Security Services..........................30
8.4.2 Requirements for IPsec Services for DDP...................31 8.4.2 Requirements for IPsec Services for DDP................31
9 IANA Considerations........................................33 9 IANA Considerations...................................33
10 References.................................................34 10 References...........................................34
10.1 Normative References......................................34 10.1 Normative References ................................34
10.2 Informative References....................................34 10.2 Informative References...............................34
11 Appendix...................................................36 11 Appendix............................................36
11.1 Receive Window sizing.....................................36 11.1 Receive Window sizing................................36
12 Authors' Addresses.........................................37 12 Authors' Addresses....................................37
13 Contributors...............................................38 13 Contributors.........................................38
14 Intellectual Property Statement............................41 14 Intellectual Property Statement........................41
15 Copyright Notice...........................................42 15 Copyright Notice.....................................42
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Table of Figures Table of Figures
Figure 1 DDP Layering.............................................7 Figure 1 DDP Layering...................................... 7
Figure 2 MPA, DDP, and RDMAP Header Alignment.....................8 Figure 2 MPA, DDP, and RDMAP Header Alignment................. 8
Figure 3 DDP Control Field.......................................15 Figure 3 DDP Control Field.................................15
Figure 4 Tagged Buffer DDP Header................................16 Figure 4 Tagged Buffer DDP Header...........................16
Figure 5 Untagged Buffer DDP Header..............................17 Figure 5 Untagged Buffer DDP Header .........................17
Figure 6 DDP Segment Format......................................18 Figure 6 DDP Segment Format ................................18
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1 Introduction 1 Introduction
Direct Data Placement Protocol (DDP) enables an Upper Layer Protocol Direct Data Placement Protocol (DDP) enables an Upper Layer Protocol
(ULP) to send data to a Data Sink without requiring the Data Sink to (ULP) to send data to a Data Sink without requiring the Data Sink to
Place the data in an intermediate buffer - thus when the data Place the data in an intermediate buffer - thus when the data
arrives at the Data Sink, the network interface can Place the data arrives at the Data Sink, the network interface can Place the data
directly into the ULP's buffer. This can enable the Data Sink to directly into the ULP's buffer. This can enable the Data Sink to
consume substantially less memory bandwidth than a buffered model consume substantially less memory bandwidth than a buffered model
because the Data Sink is not required to move the data from the because the Data Sink is not required to move the data from the
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The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119. document are to be interpreted as described in RFC 2119.
1.1 Architectural Goals 1.1 Architectural Goals
DDP has been designed with the following high-level architectural DDP has been designed with the following high-level architectural
goals: goals:
* Provide a buffer model that enables the Local Peer to Advertise * Provide a buffer model that enables the Local Peer to Advertise
a named buffer (i.e. a Tag for a buffer) to the Remote Peer, a named buffer (i.e., a Tag for a buffer) to the Remote Peer,
such that across the network the Remote Peer can Place data such that across the network the Remote Peer can Place data
into the buffer at Remote Peer specified locations. This is into the buffer at Remote Peer specified locations. This is
referred to as the Tagged Buffer Model. referred to as the Tagged Buffer Model.
* Provide a second receive buffer model which preserves ULP * Provide a second receive buffer model which preserves ULP
message boundaries from the Remote Peer and keeps the Local message boundaries from the Remote Peer and keeps the Local
Peer's buffers anonymous (i.e. Untagged). This is referred to Peer's buffers anonymous (i.e., Untagged). This is referred to
as the Untagged Buffer Model. as the Untagged Buffer Model.
* Provide reliable, in-order Delivery semantics for both Tagged * Provide reliable, in-order Delivery semantics for both Tagged
and Untagged Buffer Models. and Untagged Buffer Models.
* Provide segmentation and reassembly of ULP messages. * Provide segmentation and reassembly of ULP messages.
* Enable the ULP buffer to be used as a reassembly buffer, * Enable the ULP buffer to be used as a reassembly buffer,
without a need for a copy, even if incoming DDP Segments arrive without a need for a copy, even if incoming DDP Segments arrive
out of order. This requires the protocol to separate Data out of order. This requires the protocol to separate Data
Placement of ULP Payload contained in an incoming DDP Segment Placement of ULP Payload contained in an incoming DDP Segment
from Data Delivery of completed ULP Messages. from Data Delivery of completed ULP Messages.
* If the LLP supports multiple LLP streams within a LLP * If the Lower Layer Protocol (LLP) supports multiple LLP Streams
Connection, provide the above capabilities independently on within a LLP Connection, provide the above capabilities
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each LLP stream and enable the capability to be exported on a independently on each LLP Stream and enable the capability to
per LLP stream basis to the ULP. be exported on a per LLP Stream basis to the ULP.
1.2 Protocol Overview 1.2 Protocol Overview
DDP supports two basic data transfer models - a Tagged Buffer data DDP supports two basic data transfer models - a Tagged Buffer data
transfer model and an Untagged Buffer data transfer model. transfer model and an Untagged Buffer data transfer model.
The Tagged Buffer data transfer model requires the Data Sink to send The Tagged Buffer data transfer model requires the Data Sink to send
the Data Source an identifier for the ULP buffer, referred to as a the Data Source an identifier for the ULP buffer, referred to as a
Steering Tag (STag). The STag is transferred to the Data Source Steering Tag (STag). The STag is transferred to the Data Source
using a ULP defined method. Once the Data Source ULP has an STag for using a ULP defined method. Once the Data Source ULP has an STag for
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* For the Tagged Buffer Model, a DDP Message can start at an * For the Tagged Buffer Model, a DDP Message can start at an
arbitrary offset within the Tagged Buffer. For the Untagged arbitrary offset within the Tagged Buffer. For the Untagged
Buffer Model, a DDP Message can only start at offset 0. Buffer Model, a DDP Message can only start at offset 0.
* The Tagged Buffer Model allows multiple DDP Messages targeted * The Tagged Buffer Model allows multiple DDP Messages targeted
to a Tagged Buffer with a single ULP buffer Advertisement. The to a Tagged Buffer with a single ULP buffer Advertisement. The
Untagged Buffer Model requires associating a receive ULP buffer Untagged Buffer Model requires associating a receive ULP buffer
for each DDP Message targeted to an Untagged Buffer. for each DDP Message targeted to an Untagged Buffer.
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Either data transfer model Places a ULP Message into a DDP Message. Either data transfer model Places a ULP Message into a DDP Message.
Each DDP Message is then sliced into DDP Segments that are intended Each DDP Message is then sliced into DDP Segments that are intended
to fit within a lower-layer-protocol's (LLP) Maximum Upper Layer to fit within a lower-layer-protocol's (LLP) Maximum Upper Layer
Protocol Data Unit (MULPDU). Thus the ULP can post arbitrary size Protocol Data Unit (MULPDU). Thus the ULP can post arbitrary size
ULP Messages, containing up to 2^32 - 1 octets of ULP Payload, and ULP Messages, containing up to 2^32 - 1 octets of ULP Payload, and
DDP slices the ULP message into DDP Segments which are reassembled DDP slices the ULP message into DDP Segments which are reassembled
transparently at the Data Sink. transparently at the Data Sink.
DDP provides in-order Delivery for the ULP. However, DDP DDP provides in-order Delivery for the ULP. However, DDP
differentiates between Data Delivery and Data Placement. DDP differentiates between Data Delivery and Data Placement. DDP
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A DDP Message's payload is Delivered to the ULP when: A DDP Message's payload is Delivered to the ULP when:
* all DDP Segments of a DDP Message have been completely received * all DDP Segments of a DDP Message have been completely received
and the payload of the DDP Message has been Placed into the and the payload of the DDP Message has been Placed into the
associated ULP Buffer, associated ULP Buffer,
* all prior DDP Messages have been Placed, and * all prior DDP Messages have been Placed, and
* all prior DDP Message Deliveries have been performed. * all prior DDP Message Deliveries have been performed.
The LLP under DDP may support a single LLP stream of data per The LLP under DDP may support a single LLP Stream of data per
connection (e.g. TCP) or multiple LLP streams of data per connection connection (e.g., TCP [TCP]) or multiple LLP Streams of data per
(e.g. SCTP). But in either case, DDP is specified such that each DDP connection (e.g., SCTP [SCTP]). But in either case, DDP is specified
Stream is independent and maps to a single LLP stream. Within a such that each DDP Stream is independent and maps to a single LLP
specific DDP Stream, the LLP Stream is required to provide in-order, Stream. Within a specific DDP Stream, the LLP Stream is required to
reliable Delivery. Note that DDP has no ordering guarantees between provide in-order, reliable Delivery. Note that DDP has no ordering
DDP Streams. guarantees between DDP Streams.
A DDP protocol could potentially run over reliable Delivery LLPs or A DDP protocol could potentially run over reliable Delivery LLPs or
unreliable Delivery LLPs. This specification requires reliable, in unreliable Delivery LLPs. This specification requires reliable, in
order Delivery LLPs. order Delivery LLPs.
1.3 DDP Layering 1.3 DDP Layering
DDP is intended to be LLP independent, subject to the requirements DDP is intended to be LLP independent, subject to the requirements
defined in section 3. However, DDP was specifically defined to be defined in section 3. However, DDP was specifically defined to be
part of a family of protocols that were created to work well part of a family of protocols that were created to work well
together, as shown in Figure 1 DDP Layering. For LLP protocol together, as shown in Figure 1 DDP Layering. For LLP protocol
definitions of each LLP, see Marker PDU Aligned Framing for TCP definitions of each LLP, see Marker PDU Aligned Framing for TCP
Specification [MPA] and Stream Control Transmission Protocol (SCTP) Specification [MPA] and Stream Control Transmission Protocol (SCTP)
Direct Data Placement (DDP) Adaptation [SCTPDDP]. Direct Data Placement (DDP) Adaptation [SCTPDDP].
DDP enables direct data Placement capability for any ULP, but it has DDP enables direct data Placement capability for any ULP, but it has
been specifically designed to work well with RDMAP (see [RDMAP]), been specifically designed to work well with Remote Direct Memory
and is part of the iWARP protocol suite.
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Access Protocol (RDMAP) (see [RDMAP]), and is part of the iWARP
protocol suite.
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+-------------------+ +-------------------+
| | | |
| RDMA ULP | | RDMA ULP |
| | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | | | |
| ULP | RDMAP | | ULP | RDMAP |
| | | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | |
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| | | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1 DDP Layering Figure 1 DDP Layering
If DDP is layered below RDMAP and on top of MPA and TCP, then the If DDP is layered below RDMAP and on top of MPA and TCP, then the
respective headers and payload are arranged as follows (Note: For respective headers and payload are arranged as follows (Note: For
clarity, MPA header and CRC are included but framing markers are not clarity, MPA header and CRC are included but framing markers are not
shown.): shown.):
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0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | |
// TCP Header // // TCP Header //
| | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MPA Header | | | MPA Header | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +
| | | |
// DDP Header // // DDP Header //
| | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | |
// RDMAP Header // // RDMAP Header //
| | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | |
// //
// RDMAP ULP Payload // // RDMAP ULP Payload //
// //
| | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MPA CRC | | MPA CRC |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2 MPA, DDP, and RDMAP Header Alignment Figure 2 MPA, DDP, and RDMAP Header Alignment
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2 Glossary 2 Glossary
2.1 General 2.1 General
Advertisement (Advertised, Advertise, Advertisements, Advertises) - Advertisement (Advertised, Advertise, Advertisements, Advertises) -
The act of informing a Remote Peer that a local RDMA Buffer is The act of informing a Remote Peer that a local RDMA Buffer is
available to it. A Node makes available an RDMA Buffer for available to it. A Node makes available an RDMA Buffer for
incoming RDMA Read or RDMA Write access by informing its incoming RDMA Read or RDMA Write access by informing its
RDMA/DDP peer of the Tagged Buffer identifiers (STag, base RDMA/DDP peer of the Tagged Buffer identifiers (STag, base
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Source can be required to both send and receive RDMA/DDP Source can be required to both send and receive RDMA/DDP
Messages to transfer a data payload. Messages to transfer a data payload.
Delivery - See Data Delivery in Section 2.1. Delivery - See Data Delivery in Section 2.1.
Delivered - See Data Delivery in Section 2.1. Delivered - See Data Delivery in Section 2.1.
Delivers - See Data Delivery in Section 2.1. Delivers - See Data Delivery in Section 2.1.
iWARP - A suite of wire protocols comprised of RDMAP [RDMAP], DDP iWARP - A suite of wire protocols comprised of RDMAP [RDMAP], DDP
(this specification), and MPA [MPA]. The iWARP protocol suite (this specification), and Marker PDU Aligned Framing for TCP
may be layered above TCP, SCTP, or other transport protocols. (MPA) [MPA]. The iWARP protocol suite may be layered above TCP,
SCTP, or other transport protocols.
Local Peer - The RDMA/DDP protocol implementation on the local end Local Peer - The RDMA/DDP protocol implementation on the local end
of the connection. Used to refer to the local entity when of the connection. Used to refer to the local entity when
describing a protocol exchange or other interaction between two describing a protocol exchange or other interaction between two
Nodes. Nodes.
Node - A computing device attached to one or more links of a Node - A computing device attached to one or more links of a
network. A Node in this context does not refer to a specific network. A Node in this context does not refer to a specific
application or protocol instantiation running on the computer. A application or protocol instantiation running on the computer. A
Node may consist of one or more RNICs installed in a host Node may consist of one or more RDMA Enabled Network Interface
computer. Controllers (RNICs) installed in a host computer.
Placement - See "Data Placement" in Section 2.3 Placement - See "Data Placement" in Section 2.3
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Placed - See "Data Placement" in Section 2.3 Placed - See "Data Placement" in Section 2.3
Places - See "Data Placement" in Section 2.3 Places - See "Data Placement" in Section 2.3
Remote Peer - The RDMA/DDP protocol implementation on the opposite Remote Peer - The RDMA/DDP protocol implementation on the opposite
end of the connection. Used to refer to the remote entity when end of the connection. Used to refer to the remote entity when
describing protocol exchanges or other interactions between two describing protocol exchanges or other interactions between two
Nodes. Nodes.
RNIC - RDMA Enabled Network Interface Controller. In this context, RNIC - RDMA Enabled Network Interface Controller. In this context,
this would be a network I/O adapter or embedded controller with this would be a network I/O adapter or embedded controller with
iWARP functionality. iWARP functionality.
ULP - Upper Layer Protocol. The protocol layer above the protocol ULP - Upper Layer Protocol. The protocol layer above the protocol
layer currently being referenced. The ULP for RDMA/DDP is layer currently being referenced. The ULP for RDMA/DDP is
expected to be an OS, application, adaptation layer, or expected to be an Operating System (OS), application, adaptation
proprietary device. The RDMA/DDP documents do not specify a ULP layer, or proprietary device. The RDMA/DDP documents do not
- they provide a set of semantics that allow a ULP to be specify a ULP - they provide a set of semantics that allow a ULP
designed to utilize RDMA/DDP. to be designed to utilize RDMA/DDP.
ULP Message - The ULP data that is handed to a specific protocol ULP Message - The ULP data that is handed to a specific protocol
layer for transmission. Data boundaries are preserved as they layer for transmission. Data boundaries are preserved as they
are transmitted through iWARP. are transmitted through iWARP.
ULP Payload - The ULP data that is contained within a single ULP Payload - The ULP data that is contained within a single
protocol segment or packet (e.g. a DDP Segment). protocol segment or packet (e.g., a DDP Segment).
2.2 LLP 2.2 LLP
LLP - Lower Layer Protocol. The protocol layer beneath the protocol LLP - Lower Layer Protocol. The protocol layer beneath the protocol
layer currently being referenced. For example, for DDP the LLP layer currently being referenced. For example, for DDP the LLP
is SCTP DDP Adaptation, MPA, or other transport protocols. For is SCTP DDP Adaptation, MPA, or other transport protocols. For
RDMA, the LLP is DDP. RDMA, the LLP is DDP.
LLP Connection - Corresponds to an LLP transport-level connection LLP Connection - Corresponds to an LLP transport-level connection
between the peer LLP layers on two nodes. between the peer LLP layers on two nodes.
LLP Stream - Corresponds to a single LLP transport-level stream LLP Stream - Corresponds to a single LLP transport-level stream
between the peer LLP layers on two Nodes. One or more LLP between the peer LLP layers on two Nodes. One or more LLP
Streams may map to a single transport-level LLP Connection. For Streams may map to a single transport-level LLP Connection. For
transport protocols that support multiple streams per connection transport protocols that support multiple streams per connection
(e.g. SCTP), a LLP Stream corresponds to one transport-level (e.g., SCTP), a LLP Stream corresponds to one transport-level
stream. stream.
MULPDU - Maximum Upper Layer Protocol Data Unit (ULPDU). The current MULPDU - Maximum Upper Layer Protocol Data Unit (ULPDU). The current
maximum size of the record that is acceptable for DDP to pass to maximum size of the record that is acceptable for DDP to pass to
the LLP for transmission. the LLP for transmission.
ULPDU - Upper Layer Protocol Data Unit. The data record defined by ULPDU - Upper Layer Protocol Data Unit. The data record defined by
the layer above MPA. the layer above MPA.
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2.3 Direct Data Placement (DDP) 2.3 Direct Data Placement (DDP)
Data Placement (Placement, Placed, Places) - For DDP, this term is Data Placement (Placement, Placed, Places) - For DDP, this term is
specifically used to indicate the process of writing to a data specifically used to indicate the process of writing to a data
buffer by a DDP implementation. DDP Segments carry Placement buffer by a DDP implementation. DDP Segments carry Placement
information, which may be used by the receiving DDP information, which may be used by the receiving DDP
implementation to perform Data Placement of the DDP Segment ULP implementation to perform Data Placement of the DDP Segment ULP
Payload. See "Data Delivery" and "Direct Data Placement". Payload. See "Data Delivery" and "Direct Data Placement".
skipping to change at line 495 skipping to change at line 500
within DDP Segments may be Placed directly into its final within DDP Segments may be Placed directly into its final
destination in memory without processing of the ULP. This may destination in memory without processing of the ULP. This may
occur even when the DDP Segments arrive out of order. Out of occur even when the DDP Segments arrive out of order. Out of
order Placement support may require the Data Sink to implement order Placement support may require the Data Sink to implement
the LLP and DDP as one functional block. the LLP and DDP as one functional block.
Direct Data Placement Protocol (DDP) - Also, a wire protocol that Direct Data Placement Protocol (DDP) - Also, a wire protocol that
supports Direct Data Placement by associating explicit memory supports Direct Data Placement by associating explicit memory
buffer placement information with the LLP payload units. buffer placement information with the LLP payload units.
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Message Offset (MO) - For the DDP Untagged Buffer Model, specifies Message Offset (MO) - For the DDP Untagged Buffer Model, specifies
the offset, in octets, from the start of a DDP Message. the offset, in octets, from the start of a DDP Message.
Message Sequence Number (MSN) - For the DDP Untagged Buffer Model, Message Sequence Number (MSN) - For the DDP Untagged Buffer Model,
specifies a sequence number that is increasing with each DDP specifies a sequence number that is increasing with each DDP
Message. Message.
Protection Domain (PD) - A Mechanism used to associate a DDP Stream Protection Domain (PD) - A Mechanism used to associate a DDP Stream
and an STag. Under this mechanism, the use of an STag is valid and an STag. Under this mechanism, the use of an STag is valid
on a DDP Stream if the STag has the same Protection Domain on a DDP Stream if the STag has the same Protection Domain
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Untagged Buffer - A buffer that is not explicitly Advertised to the Untagged Buffer - A buffer that is not explicitly Advertised to the
Remote Peer. Remote Peer.
Untagged Buffer Model - A DDP data transfer model used to transfer Untagged Buffer Model - A DDP data transfer model used to transfer
Untagged Buffers from the Local Peer to the Remote Peer. Untagged Buffers from the Local Peer to the Remote Peer.
Untagged DDP Message - A DDP Message that targets an Untagged Untagged DDP Message - A DDP Message that targets an Untagged
Buffer. Buffer.
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3 Reliable Delivery LLP Requirements 3 Reliable Delivery LLP Requirements
Any protocol that can serve as an LLP to DDP MUST meet the following Any protocol that can serve as an LLP to DDP MUST meet the following
requirements. requirements.
1. LLPs MUST expose MULPDU & MULPDU Changes. This is required so 1. LLPs MUST expose MULPDU & MULPDU Changes. This is required so
that the DDP layer can perform segmentation aligned with the that the DDP layer can perform segmentation aligned with the
MULPDU and can adapt as MULPDU changes come about. The corner MULPDU and can adapt as MULPDU changes come about. The corner
case of how to handle outstanding requests during a MULPDU case of how to handle outstanding requests during a MULPDU
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4. The LLP MUST preserve DDP Segment and Message boundaries at the 4. The LLP MUST preserve DDP Segment and Message boundaries at the
Data Sink. Data Sink.
5. The LLP MAY provide the incoming segments out of order for 5. The LLP MAY provide the incoming segments out of order for
Placement, but if it does, it MUST also provide information that Placement, but if it does, it MUST also provide information that
specifies what the sender specified order was. specifies what the sender specified order was.
6. LLP MUST provide a strong digest (at least equivalent to CRC32- 6. LLP MUST provide a strong digest (at least equivalent to CRC32-
C) to cover at least the DDP Segment. It is believed that some C) to cover at least the DDP Segment. It is believed that some
of the existing data integrity digests are not sufficient and of the existing data integrity digests are not sufficient and
that direct memory transfer semantics require a stronger digest that direct memory transfer semantics requires a stronger digest
than, for example, a simple checksum. than, for example, a simple checksum.
7. On receive, the LLP MUST provide the length of the DDP Segment 7. On receive, the LLP MUST provide the length of the DDP Segment
received. This ensures that DDP does not have to carry a length received. This ensures that DDP does not have to carry a length
field in its header. field in its header.
8. If an LLP does not support teardown of a LLP stream independent 8. If an LLP does not support teardown of a LLP Stream independent
of other LLP streams and a DDP error occurs on a specific DDP of other LLP Streams and a DDP error occurs on a specific DDP
Stream, then the LLP MUST label the associated LLP stream as an Stream, then the LLP MUST label the associated LLP Stream as an
erroneous LLP stream and MUST NOT allow any further data erroneous LLP Stream and MUST NOT allow any further data
transfer on that LLP stream after DDP requests the associated transfer on that LLP Stream after DDP requests the associated
DDP Stream to be torn down. DDP Stream to be torn down.
9. For a specific LLP Stream, the LLP MUST provide a mechanism to 9. For a specific LLP Stream, the LLP MUST provide a mechanism to
indicate that the LLP Stream has been gracefully torn down. For indicate that the LLP Stream has been gracefully torn down. For
a specific LLP Connection, the LLP MUST provide a mechanism to a specific LLP Connection, the LLP MUST provide a mechanism to
indicate that the LLP Connection has been gracefully torn down. indicate that the LLP Connection has been gracefully torn down.
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Note that if the LLP does not allow an LLP Stream to be torn Note that if the LLP does not allow an LLP Stream to be torn
down independently of the LLP Connection, the above requirements down independently of the LLP Connection, the above requirements
allow the LLP to notify DDP of both events at the same time. allow the LLP to notify DDP of both events at the same time.
10. For a specific LLP Connection, when all LLP Streams are either 10. For a specific LLP Connection, when all LLP Streams are either
gracefully torn down or are labeled as erroneous LLP streams, gracefully torn down or are labeled as erroneous LLP Streams,
the LLP Connection MUST be torn down. the LLP Connection MUST be torn down.
11. The LLP MUST NOT pass a duplicate DDP Segment to the DDP Layer 11. The LLP MUST NOT pass a duplicate DDP Segment to the DDP Layer
after it has passed all the previous DDP Segments to the DDP after it has passed all the previous DDP Segments to the DDP
Layer and the associated ordering information for the previous Layer and the associated ordering information for the previous
DDP Segments and the current DDP Segment. DDP Segments and the current DDP Segment.
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4 Header Format 4 Header Format
DDP has two different header formats: one for Data Placement into DDP has two different header formats: one for Data Placement into
Tagged Buffers, and the other for Data Placement into Untagged Tagged Buffers, and the other for Data Placement into Untagged
Buffers. See Section 5.1 for a description of the two models. Buffers. See Section 5.1 for a description of the two models.
4.1 DDP Control Field 4.1 DDP Control Field
The first 8 bits of the DDP Header carry a DDP Control Field that is The first 8 bits of the DDP Header carry a DDP Control Field that is
skipping to change at line 669 skipping to change at line 674
Delivered to the ULP after: Delivered to the ULP after:
. Placement of all DDP Segments of this DDP Message and all . Placement of all DDP Segments of this DDP Message and all
prior DDP Messages, and prior DDP Messages, and
. Delivery of each prior DDP Message. . Delivery of each prior DDP Message.
If the Last flag is set to zero, the DDP Segment is an If the Last flag is set to zero, the DDP Segment is an
intermediate DDP Segment. intermediate DDP Segment.
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Rsvd - Reserved: 4 bits. Rsvd - Reserved: 4 bits.
Reserved for future use by the DDP protocol. This field MUST be Reserved for future use by the DDP protocol. This field MUST be
set to zero on transmit, and not checked on receive. set to zero on transmit, and not checked on receive.
DV - Direct Data Placement Protocol Version: 2 bits. DV - Direct Data Placement Protocol Version: 2 bits.
The version of the DDP Protocol in use. This field MUST be set The version of the DDP Protocol in use. This field MUST be set
to one to indicate the version of the specification described to one to indicate the version of the specification described
in this document. The value of DV MUST be the same for all the in this document. The value of DV MUST be the same for all the
skipping to change at line 724 skipping to change at line 729
specific DDP Message MUST contain the same value for this specific DDP Message MUST contain the same value for this
field. The Data Source MUST ensure that each DDP Segment within field. The Data Source MUST ensure that each DDP Segment within
a specific DDP Message contains the same value for this field. a specific DDP Message contains the same value for this field.
STag - Steering Tag: 32 bits. STag - Steering Tag: 32 bits.
The Steering Tag identifies the Data Sink's Tagged Buffer. The The Steering Tag identifies the Data Sink's Tagged Buffer. The
STag MUST be valid for this DDP Stream. The STag is associated STag MUST be valid for this DDP Stream. The STag is associated
with the DDP Stream through a mechanism that is outside the with the DDP Stream through a mechanism that is outside the
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scope of the DDP Protocol specification. At the Data Source, scope of the DDP Protocol specification. At the Data Source,
DDP MUST set the STag field to the value specified by the ULP. DDP MUST set the STag field to the value specified by the ULP.
At the Data Sink, the DDP MUST provide the STag field when the At the Data Sink, the DDP MUST provide the STag field when the
ULP Message is delivered. Each DDP Segment within a specific ULP Message is delivered. Each DDP Segment within a specific
DDP Message MUST contain the same value for this field and MUST DDP Message MUST contain the same value for this field and MUST
be the value supplied by the ULP. The Data Source MUST ensure be the value supplied by the ULP. The Data Source MUST ensure
that each DDP Segment within a specific DDP Message contains that each DDP Segment within a specific DDP Message contains
the same value for this field. the same value for this field.
TO - Tagged Offset: 64 bits. TO - Tagged Offset: 64 bits.
skipping to change at line 777 skipping to change at line 782
RsvdULP - Reserved for use by the ULP: 40 bits. RsvdULP - Reserved for use by the ULP: 40 bits.
The RsvdULP field is opaque to the DDP protocol and can be The RsvdULP field is opaque to the DDP protocol and can be
structured in any way by the ULP. At the Data Source, DDP MUST structured in any way by the ULP. At the Data Source, DDP MUST
set RsvdULP Field to the value specified by the ULP. It is set RsvdULP Field to the value specified by the ULP. It is
transferred unmodified from the Data Source to the Data Sink. transferred unmodified from the Data Source to the Data Sink.
At the Data Sink, DDP MUST provide RsvdULP field to the ULP At the Data Sink, DDP MUST provide RsvdULP field to the ULP
when the ULP Message is Delivered. Each DDP Segment within a when the ULP Message is Delivered. Each DDP Segment within a
specific DDP Message MUST contain the same value for the specific DDP Message MUST contain the same value for the
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RsvdULP field. At the Data Sink, the DDP implementation is NOT RsvdULP field. At the Data Sink, the DDP implementation is NOT
REQUIRED to verify that the same value is present in the REQUIRED to verify that the same value is present in the
RsvdULP field of each DDP Segment within a specific DDP Message RsvdULP field of each DDP Segment within a specific DDP Message
and MAY provide the value from any one of the received DDP and MAY provide the value from any one of the received DDP
Segment to the ULP when the ULP Message is Delivered. Segment to the ULP when the ULP Message is Delivered.
QN - Queue Number: 32 bits. QN - Queue Number: 32 bits.
The Queue Number identifies the Data Sink's Untagged Buffer The Queue Number identifies the Data Sink's Untagged Buffer
queue referenced by this header. Each DDP segment within a queue referenced by this header. Each DDP segment within a
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Each DDP Segment MUST contain a DDP Header. Each DDP Segment may Each DDP Segment MUST contain a DDP Header. Each DDP Segment may
also contain ULP Payload. Following is the DDP Segment format: also contain ULP Payload. Following is the DDP Segment format:
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DDP | | | DDP | |
| Header| ULP Payload (if any) | | Header| ULP Payload (if any) |
| | | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6 DDP Segment Format Figure 6 DDP Segment Format
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5 Data Transfer 5 Data Transfer
DDP supports multi-segment DDP Messages. Each DDP Message is DDP supports multi-segment DDP Messages. Each DDP Message is
composed of one or more DDP Segments. Each DDP Segment contains a composed of one or more DDP Segments. Each DDP Segment contains a
DDP Header. The DDP Header contains the information required by the DDP Header. The DDP Header contains the information required by the
receiver to Place any ULP Payload included in the DDP Segment. receiver to Place any ULP Payload included in the DDP Segment.
5.1 DDP Tagged or Untagged Buffer Models 5.1 DDP Tagged or Untagged Buffer Models
skipping to change at line 848 skipping to change at line 853
5.1.1 Tagged Buffer Model 5.1.1 Tagged Buffer Model
The Tagged Buffer Model is used by the Data Source to transfer a DDP The Tagged Buffer Model is used by the Data Source to transfer a DDP
Message into a Tagged Buffer at the Data Sink that has been Message into a Tagged Buffer at the Data Sink that has been
previously Advertised to the Data Source. An STag identifies a previously Advertised to the Data Source. An STag identifies a
Tagged Buffer. For the Placement of a DDP Message using the Tagged Tagged Buffer. For the Placement of a DDP Message using the Tagged
Buffer model, the STag is used to identify the buffer, and the TO is Buffer model, the STag is used to identify the buffer, and the TO is
used to identify the offset within the Tagged Buffer into which the used to identify the offset within the Tagged Buffer into which the
ULP Payload is transferred. The protocol used to Advertise the ULP Payload is transferred. The protocol used to Advertise the
Tagged Buffer is outside the scope of this specification (i.e. ULP Tagged Buffer is outside the scope of this specification (i.e., ULP
specific). A DDP Message can start at an arbitrary TO within a specific). A DDP Message can start at an arbitrary TO within a
Tagged Buffer. Tagged Buffer.
Additionally, a Tagged Buffer can potentially be written multiple Additionally, a Tagged Buffer can potentially be written multiple
times. This might be done for error recovery or because a buffer is times. This might be done for error recovery or because a buffer is
being re-used after some ULP specific synchronization mechanism. being re-used after some ULP specific synchronization mechanism.
5.1.2 Untagged Buffer Model 5.1.2 Untagged Buffer Model
The Untagged Buffer Model is used by the Data Source to transfer a The Untagged Buffer Model is used by the Data Source to transfer a
skipping to change at line 881 skipping to change at line 886
communicate how many buffers have been queued is outside the scope communicate how many buffers have been queued is outside the scope
of this specification. Similarly, the exact implementation of the of this specification. Similarly, the exact implementation of the
buffer queue is outside the scope of this specification. buffer queue is outside the scope of this specification.
5.2 Segmentation and Reassembly of a DDP Message 5.2 Segmentation and Reassembly of a DDP Message
At the Data Source, the DDP layer MUST segment the data contained in At the Data Source, the DDP layer MUST segment the data contained in
a ULP message into a series of DDP Segments, where each DDP Segment a ULP message into a series of DDP Segments, where each DDP Segment
contains a DDP Header and ULP Payload, and MUST be no larger than contains a DDP Header and ULP Payload, and MUST be no larger than
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the MULPDU value advertised by the LLP. The ULP Message Length MUST the MULPDU value advertised by the LLP. The ULP Message Length MUST
be less than 2^32. At the Data Source, the DDP layer MUST send all be less than 2^32. At the Data Source, the DDP layer MUST send all
the data contained in the ULP message. At the Data Sink, the DDP the data contained in the ULP message. At the Data Sink, the DDP
layer MUST Place the ULP Payload contained in all valid incoming DDP layer MUST Place the ULP Payload contained in all valid incoming DDP
Segments associated with a DDP Message into the ULP Buffer. Segments associated with a DDP Message into the ULP Buffer.
DDP Message segmentation at the Data Source is accomplished by DDP Message segmentation at the Data Source is accomplished by
identifying a DDP Message (which corresponds one-to-one with a ULP identifying a DDP Message (which corresponds one-to-one with a ULP
Message) uniquely and then, for each associated DDP Segment of a DDP Message) uniquely and then, for each associated DDP Segment of a DDP
Message, by specifying an octet offset for the portion of the ULP Message, by specifying an octet offset for the portion of the ULP
skipping to change at line 936 skipping to change at line 941
of the STag effectively enables the ULP to implement of the STag effectively enables the ULP to implement
segmentation and reassembly due to ULP specific constraints. segmentation and reassembly due to ULP specific constraints.
See [RDMAP] for details of how this is done. See [RDMAP] for details of how this is done.
A different implementation of a ULP could use an Untagged DDP A different implementation of a ULP could use an Untagged DDP
Message sent after the Tagged DDP Message which details the Message sent after the Tagged DDP Message which details the
initial TO for the STag that was used in the Tagged DDP initial TO for the STag that was used in the Tagged DDP
Message. And finally, another implementation of a ULP could Message. And finally, another implementation of a ULP could
choose to always use an initial TO of zero such that no choose to always use an initial TO of zero such that no
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additional message is required to convey the initial TO used in additional message is required to convey the initial TO used in
a Tagged DDP Message. a Tagged DDP Message.
Regardless of whether the ULP chooses to recover the original ULP Regardless of whether the ULP chooses to recover the original ULP
Message boundary at the Data Sink for a Tagged DDP Message, DDP Message boundary at the Data Sink for a Tagged DDP Message, DDP
supports segmentation and reassembly of the Tagged DDP Message. The supports segmentation and reassembly of the Tagged DDP Message. The
STag is used to identify the ULP Buffer at the Data Sink and the TO STag is used to identify the ULP Buffer at the Data Sink and the TO
is used to identify the octet-offset within the ULP Buffer is used to identify the octet-offset within the ULP Buffer
referenced by the STag. The ULP at the Data Source MUST specify the referenced by the STag. The ULP at the Data Source MUST specify the
STag and the initial TO when the ULP Message is handed to DDP. STag and the initial TO when the ULP Message is handed to DDP.
skipping to change at line 990 skipping to change at line 995
* SHOULD transmit DDP Segments within a DDP Message in increasing * SHOULD transmit DDP Segments within a DDP Message in increasing
MO order for Untagged DDP Messages and in increasing TO order MO order for Untagged DDP Messages and in increasing TO order
for Tagged DDP Messages. for Tagged DDP Messages.
At the Data Sink, DDP (Note: The following rules are motivated by At the Data Sink, DDP (Note: The following rules are motivated by
LLP implementations that separate Placement and Delivery.): LLP implementations that separate Placement and Delivery.):
* MAY perform Placement of DDP Segments out of order, * MAY perform Placement of DDP Segments out of order,
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* MAY perform Placement of a DDP Segment more than once, * MAY perform Placement of a DDP Segment more than once,
* MUST Deliver a DDP Message to the ULP at most once, * MUST Deliver a DDP Message to the ULP at most once,
* MUST Deliver DDP Messages to the ULP in the order they were * MUST Deliver DDP Messages to the ULP in the order they were
sent by the Data Source. sent by the Data Source.
5.4 DDP Message Completion & Delivery 5.4 DDP Message Completion & Delivery
At the Data Source, DDP Message transfer is considered completed At the Data Source, DDP Message transfer is considered completed
skipping to change at line 1027 skipping to change at line 1032
At the Data Sink, DDP MUST provide the ULP Message Length to the ULP At the Data Sink, DDP MUST provide the ULP Message Length to the ULP
when an Untagged DDP Message is Delivered. The ULP Message Length when an Untagged DDP Message is Delivered. The ULP Message Length
may be calculated by adding the MO and the ULP Payload length in the may be calculated by adding the MO and the ULP Payload length in the
last DDP Segment (with the Last flag set) of an Untagged DDP last DDP Segment (with the Last flag set) of an Untagged DDP
Message. Message.
At the Data Sink, DDP MUST provide the RsvdULP Field of the DDP At the Data Sink, DDP MUST provide the RsvdULP Field of the DDP
Message to the ULP when the DDP Message is delivered. Message to the ULP when the DDP Message is delivered.
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6 DDP Stream Setup & Teardown 6 DDP Stream Setup & Teardown
This section describes LLP independent issues related to DDP Stream This section describes LLP independent issues related to DDP Stream
setup and teardown. setup and teardown.
6.1 DDP Stream Setup 6.1 DDP Stream Setup
It is expected that the ULP will use a mechanism outside the scope It is expected that the ULP will use a mechanism outside the scope
of this specification to establish an LLP Connection, and that the of this specification to establish an LLP Connection, and that the
LLP Connection will support one or more LLP Streams (e.g. MPA/TCP or LLP Connection will support one or more LLP Streams (e.g., MPA/TCP
SCTP). After the LLP sets up the LLP Stream, it will enable a DDP or SCTP). After the LLP sets up the LLP Stream, it will enable a DDP
Stream on a specific LLP Stream at an appropriate point. Stream on a specific LLP Stream at an appropriate point.
The ULP is required to enable both endpoints of an LLP Stream for The ULP is required to enable both endpoints of an LLP Stream for
DDP data transfer at the same time, in both directions; this is DDP data transfer at the same time, in both directions; this is
necessary so that the Data Sink can properly recognize the DDP necessary so that the Data Sink can properly recognize the DDP
Segments. Segments.
6.2 DDP Stream Teardown 6.2 DDP Stream Teardown
DDP MUST NOT independently initiate Stream Teardown. DDP either DDP MUST NOT independently initiate Stream Teardown. DDP either
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torn down. torn down.
If the Local Peer LLP supports a half-closed LLP Stream, on the If the Local Peer LLP supports a half-closed LLP Stream, on the
receipt of a LLP graceful teardown request of the DDP Stream, DDP receipt of a LLP graceful teardown request of the DDP Stream, DDP
SHOULD indicate the half-closed state to the ULP, and continue to SHOULD indicate the half-closed state to the ULP, and continue to
process outbound data transfer requests normally. Following this process outbound data transfer requests normally. Following this
event, when the Local Peer ULP requests graceful teardown, DDP MUST event, when the Local Peer ULP requests graceful teardown, DDP MUST
indicate to the LLP that it SHOULD perform a graceful close of the indicate to the LLP that it SHOULD perform a graceful close of the
other half of the LLP Stream. other half of the LLP Stream.
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If the Local Peer LLP supports a half-closed LLP Stream, on the If the Local Peer LLP supports a half-closed LLP Stream, on the
receipt of a ULP graceful half-close teardown request of the DDP receipt of a ULP graceful half-close teardown request of the DDP
Stream, DDP SHOULD keep data reception enabled on the other half of Stream, DDP SHOULD keep data reception enabled on the other half of
the LLP stream. the LLP Stream.
6.2.2 DDP Abortive Teardown 6.2.2 DDP Abortive Teardown
As previously mentioned, DDP does not independently terminate a DDP As previously mentioned, DDP does not independently terminate a DDP
Stream. Thus any of the following fatal errors on a DDP Stream MUST Stream. Thus any of the following fatal errors on a DDP Stream MUST
cause DDP to indicate to the ULP that a fatal error has occurred: cause DDP to indicate to the ULP that a fatal error has occurred:
* Underlying LLP Connection or LLP Stream is lost. * Underlying LLP Connection or LLP Stream is lost.
* Underlying LLP reports a catastrophic error. * Underlying LLP reports a fatal error.
* DDP Header has one or more invalid fields. * DDP Header has one or more invalid fields.
If the LLP indicates to the ULP that a fatal error has occurred, the If the LLP indicates to the ULP that a fatal error has occurred, the
DDP layer SHOULD report the error to the ULP (see Section 7.2, DDP DDP layer SHOULD report the error to the ULP (see Section 7.2, DDP
Error Numbers) and complete all outstanding ULP requests with an Error Numbers) and complete all outstanding ULP requests with an
error. If the underlying LLP Stream is still intact, DDP SHOULD error. If the underlying LLP Stream is still intact, DDP SHOULD
continue to allow the ULP to transfer additional DDP Messages on the continue to allow the ULP to transfer additional DDP Messages on the
outgoing half connection after the fatal error was indicated to the outgoing half connection after the fatal error was indicated to the
ULP. This enables the ULP to transfer an error syndrome to the ULP. This enables the ULP to transfer an error syndrome to the
Remote Peer. After indicating to the ULP a fatal error has occurred, Remote Peer. After indicating to the ULP a fatal error has occurred,
the DDP Stream MUST NOT be terminated until the Local Peer ULP the DDP Stream MUST NOT be terminated until the Local Peer ULP
indicates to the DDP layer that the DDP Stream should be abortively indicates to the DDP layer that the DDP Stream should be abortively
torndown. torndown.
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7 Error Semantics 7 Error Semantics
All LLP errors reported to DDP SHOULD be passed up to the ULP. All LLP errors reported to DDP SHOULD be passed up to the ULP.
7.1 Errors detected at the Data Sink 7.1 Errors detected at the Data Sink
For non-zero length Untagged DDP Segments, the DDP Segment MUST be For non-zero length Untagged DDP Segments, the DDP Segment MUST be
validated before Placement by verifying: validated before Placement by verifying:
skipping to change at line 1165 skipping to change at line 1170
available to handle the incoming DDP Segments. available to handle the incoming DDP Segments.
For non-zero length Tagged DDP Segments, the segment MUST be For non-zero length Tagged DDP Segments, the segment MUST be
validated before Placement by verifying: validated before Placement by verifying:
1. The STag is valid for this stream. 1. The STag is valid for this stream.
2. The STag has an associated buffer that allows Placement of the 2. The STag has an associated buffer that allows Placement of the
payload. payload.
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3. The TO falls in the range of legal offsets registered for the 3. The TO falls in the range of legal offsets registered for the
STag. STag.
4. The sum of the DDP Segment payload length and the TO falls in 4. The sum of the DDP Segment payload length and the TO falls in
the range of legal offsets registered for the STag. the range of legal offsets registered for the STag.
5. A 64-bit unsigned sum of the DDP Segment payload length and the 5. A 64-bit unsigned sum of the DDP Segment payload length and the
TO does not wrap. TO does not wrap.
If the DDP layer detects any of the receive errors listed in this If the DDP layer detects any of the receive errors listed in this
skipping to change at line 1213 skipping to change at line 1218
0x2 Untagged Buffer Error 0x2 Untagged Buffer Error
0x01 Invalid QN 0x01 Invalid QN
0x02 Invalid MSN - no buffer available 0x02 Invalid MSN - no buffer available
0x03 Invalid MSN - MSN range is not valid 0x03 Invalid MSN - MSN range is not valid
0x04 Invalid MO 0x04 Invalid MO
0x05 DDP Message too long for available buffer 0x05 DDP Message too long for available buffer
0x06 Invalid DDP version 0x06 Invalid DDP version
0x3 Rsvd Reserved for the use by the LLP 0x3 Rsvd Reserved for the use by the LLP
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8 Security Considerations 8 Security Considerations
This section discusses both protocol-specific considerations and the This section discusses both protocol-specific considerations and the
implications of using DDP with existing security mechanisms. The implications of using DDP with existing security mechanisms. The
security requirements for the DDP implementation are provided at the security requirements for the DDP implementation are provided at the
end of the section. A more detailed analysis of the security issues end of the section. A more detailed analysis of the security issues
around the implementation and the use of the DDP can be found in around the implementation and the use of the DDP can be found in
[RDMASEC]. [RDMASEC].
The IPsec requirements for RDDP are based on the version of IPsec
specified in RFC 2401 [IPSEC] and related RFCs, as profiled by RFC
3723 [RFC 3723], despite the existence of a newer version of IPsec
specified in RFC 4301 [RFC 4301] and related RFCs. One of the
important early applications of the RDDP protocols is their use with
iSCSI [iSER]; RDDP's IPsec requirements follow those of IPsec in
order to facilitate that usage by allowing a common profile of IPsec
to be used with iSCSI and the RDDP protocols. In the future, RFC
3723 may be updated to the newer version of IPsec, the IPsec
security requirements of any such update should apply uniformly to
iSCSI and the RDDP protocols.
8.1 Protocol-specific Security Considerations 8.1 Protocol-specific Security Considerations
The vulnerabilities of DDP to active third-party interference are no The vulnerabilities of DDP to active third-party interference are no
greater than any other protocol running over transport protocols greater than any other protocol running over transport protocols
such as TCP and SCTP over IP. A third party, by injecting spoofed such as TCP and SCTP over IP. A third party, by injecting spoofed
packets into the network that are Delivered to a DDP Data Sink, packets into the network that are Delivered to a DDP Data Sink,
could launch a variety of attacks that exploit DDP-specific could launch a variety of attacks that exploit DDP-specific
behavior. Since DDP directly or indirectly exposes memory addresses behavior. Since DDP directly or indirectly exposes memory addresses
on the wire, the Placement information carried in each DDP Segment on the wire, the Placement information carried in each DDP Segment
must be validated, including invalid STag and octet level must be validated, including invalid STag and octet level
skipping to change at line 1255 skipping to change at line 1272
Protection Domain (PD) association and a DDP Stream association. Protection Domain (PD) association and a DDP Stream association.
Under the Protection Domain (PD) association, a unique Protection Under the Protection Domain (PD) association, a unique Protection
Domain Identifier (PD ID) is created and used locally to associate Domain Identifier (PD ID) is created and used locally to associate
an STag with a set of DDP Streams. Under this mechanism, the use of an STag with a set of DDP Streams. Under this mechanism, the use of
the STag is only permitted on the DDP Streams that have the same PD the STag is only permitted on the DDP Streams that have the same PD
ID as the STag. For an incoming DDP Segment of a Tagged DDP Message ID as the STag. For an incoming DDP Segment of a Tagged DDP Message
on a DDP Stream, if the PD ID of the DDP Stream is not the same as on a DDP Stream, if the PD ID of the DDP Stream is not the same as
the PD ID of the STag targeted by the Tagged DDP Message, then the the PD ID of the STag targeted by the Tagged DDP Message, then the
DDP Segment is not placed and the DDP layer MUST surface a local DDP Segment is not placed and the DDP layer MUST surface a local
Shah, et. al. Expires March 2007 27
error to the ULP. Note that the PD ID is locally defined, and cannot error to the ULP. Note that the PD ID is locally defined, and cannot
be directly manipulated by the Remote Peer. be directly manipulated by the Remote Peer.
Under the DDP Stream association, a DDP Stream is identified locally Under the DDP Stream association, a DDP Stream is identified locally
by a unique DDP Stream identifier (ID). An STag is associated with a by a unique DDP Stream identifier (ID). An STag is associated with a
DDP Stream by using a DDP Stream ID. In this case, for an incoming DDP Stream by using a DDP Stream ID. In this case, for an incoming
DDP Segment of a Tagged DDP Message on a DDP Stream, if the DDP DDP Segment of a Tagged DDP Message on a DDP Stream, if the DDP
Stream ID of the DDP Stream is not the same as the DDP Stream ID of Stream ID of the DDP Stream is not the same as the DDP Stream ID of
the STag targeted by the Tagged DDP Message, then the DDP Segment is the STag targeted by the Tagged DDP Message, then the DDP Segment is
not placed and the DDP layer MUST surface a local error to the ULP. not placed and the DDP layer MUST surface a local error to the ULP.
Note that the DDP Stream ID is locally defined, and cannot be Note that the DDP Stream ID is locally defined, and cannot be
directly manipulated by the Remote Peer. directly manipulated by the Remote Peer.
Shah, et. al. Expires January 2007 27
A ULP SHOULD associate an STag with at least one DDP Stream. DDP A ULP SHOULD associate an STag with at least one DDP Stream. DDP
MUST support Protection Domain association and DDP Stream MUST support Protection Domain association and DDP Stream
association mechanisms for associating an STag and a DDP Stream. association mechanisms for associating an STag and a DDP Stream.
8.3 Security Requirements 8.3 Security Requirements
[RDMASEC] defines the security model and general assumptions for [RDMASEC] defines the security model and general assumptions for
RDMAP/DDP. This subsection provides the security requirements for RDMAP/DDP. This subsection provides the security requirements for
the DDP implementation. For more details on the type of attacks, the DDP implementation. For more details on the type of attacks,
type of attackers, trust models, and resource sharing for the DDP type of attackers, trust models, and resource sharing for the DDP
skipping to change at line 1308 skipping to change at line 1326
buffers in order to directly Place data into a user buffer and is buffers in order to directly Place data into a user buffer and is
therefore constrained by the same techniques mentioned to guard therefore constrained by the same techniques mentioned to guard
against attempts to read or write from unauthorized memory regions. against attempts to read or write from unauthorized memory regions.
DDP does not require a node to open its buffers to arbitrary attacks DDP does not require a node to open its buffers to arbitrary attacks
over the DDP Stream. It may access ULP memory only to the extent over the DDP Stream. It may access ULP memory only to the extent
that the ULP has enabled and authorized it to do so. The STag that the ULP has enabled and authorized it to do so. The STag
access control model is defined in [RDMASEC]. Specific security access control model is defined in [RDMASEC]. Specific security
operations include: operations include:
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1. STags are only valid over the exact byte range established by the 1. STags are only valid over the exact byte range established by the
ULP. DDP MUST provide a mechanism for the ULP to establish and ULP. DDP MUST provide a mechanism for the ULP to establish and
revoke the TO range associated with the ULP Buffer referenced by revoke the TO range associated with the ULP Buffer referenced by
the STag. the STag.
2. STags are only valid for the duration established by the ULP. The 2. STags are only valid for the duration established by the ULP. The
ULP may revoke them at any time, in accordance with its own upper ULP may revoke them at any time, in accordance with its own upper
layer protocol requirements. DDP MUST provide a mechanism for the layer protocol requirements. DDP MUST provide a mechanism for the
ULP to establish and revoke STag validity. ULP to establish and revoke STag validity.
3. DDP MUST provide a mechanism for the ULP to communicate the 3. DDP MUST provide a mechanism for the ULP to communicate the
association between a STag and a specific DDP Stream. association between a STag and a specific DDP Stream.
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4. A ULP may only expose memory to remote access to the extent that 4. A ULP may only expose memory to remote access to the extent that
it already had access to that memory itself. it already had access to that memory itself.
5. If an STag is not valid on a DDP Stream, DDP MUST pass the invalid 5. If an STag is not valid on a DDP Stream, DDP MUST pass the invalid
access attempt to the ULP. The ULP may provide a mechanism for access attempt to the ULP. The ULP may provide a mechanism for
terminating the DDP Stream. terminating the DDP Stream.
Further, DDP provides a mechanism that directly Places incoming Further, DDP provides a mechanism that directly Places incoming
payloads in user-mode ULP Buffers. This avoids the risks of prior payloads in user-mode ULP Buffers. This avoids the risks of prior
solutions that relied upon exposing system buffers for incoming solutions that relied upon exposing system buffers for incoming
payloads. payloads.
skipping to change at line 1361 skipping to change at line 1378
revoke the association of a ULP Buffer to an STag and TO range. revoke the association of a ULP Buffer to an STag and TO range.
5. An RNIC MUST provide a mechanism for the ULP to establish and 5. An RNIC MUST provide a mechanism for the ULP to establish and
revoke read, write, or read and write access to the ULP Buffer revoke read, write, or read and write access to the ULP Buffer
referenced by an STag. referenced by an STag.
6. An RNIC MUST ensure that the network interface can no longer 6. An RNIC MUST ensure that the network interface can no longer
modify an advertised buffer after the ULP revokes remote access modify an advertised buffer after the ULP revokes remote access
rights for an STag. rights for an STag.
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7. An RNIC MUST NOT enable firmware to be loaded on the RNIC 7. An RNIC MUST NOT enable firmware to be loaded on the RNIC
directly from an untrusted Local Peer or Remote Peer, unless directly from an untrusted Local Peer or Remote Peer, unless
the Peer is properly authenticated (by a mechanism outside the the Peer is properly authenticated (by a mechanism outside the
scope of this specification. The mechanism presumably entails scope of this specification. The mechanism presumably entails
authenticating that the remote ULP has the right to perform the authenticating that the remote ULP has the right to perform the
update), and the update is done via a secure protocol, such as update), and the update is done via a secure protocol, such as
IPsec. IPsec.
8.3.2 Privileged Resources Manager Requirement 8.3.2 Privileged Resources Manager Requirement
The PRM MUST implement the security semantics described below. The PRM MUST implement the security semantics described below.
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1. All Non-Privileged ULP interactions with the RNIC Engine that 1. All Non-Privileged ULP interactions with the RNIC Engine that
could affect other ULPs MUST be done using the Privileged could affect other ULPs MUST be done using the Privileged
Resource Manager as a proxy. Resource Manager as a proxy.
2. All ULP resource allocation requests for scarce resources MUST 2. All ULP resource allocation requests for scarce resources MUST
also be done using a Privileged Resource Manager. also be done using a Privileged Resource Manager.
3. The Privileged Resource Manager MUST NOT assume different ULPs 3. The Privileged Resource Manager MUST NOT assume different ULPs
share Partial Mutual Trust unless there is a mechanism to share Partial Mutual Trust unless there is a mechanism to
ensure that the ULPs do indeed share partial mutual trust. ensure that the ULPs do indeed share partial mutual trust.
skipping to change at line 1402 skipping to change at line 1419
from allocating more than its fair share of resources. from allocating more than its fair share of resources.
If an RNIC provides the ability to share receive buffers across If an RNIC provides the ability to share receive buffers across
multiple DDP Streams, the combination of the RNIC and the multiple DDP Streams, the combination of the RNIC and the
Privileged Resource Manager MUST be able to detect if the Privileged Resource Manager MUST be able to detect if the
Remote Peer is attempting to consume more than its fair share Remote Peer is attempting to consume more than its fair share
of resources so that the Local Peer can apply countermeasures of resources so that the Local Peer can apply countermeasures
to detect and prevent the attack. to detect and prevent the attack.
8.4 Security Services for DDP 8.4 Security Services for DDP
DDP uses an IP based network services, therefore, all exchanged DDP DDP uses IP based network services, therefore, all exchanged DDP
Segments are vulnerable to spoofing, tampering and information Segments are vulnerable to spoofing, tampering and information
disclosure attacks. If a DDP Stream may be subject to impersonation disclosure attacks. If a DDP Stream may be subject to impersonation
attacks, or Stream hijacking attacks, it is highly RECOMMENDED that attacks, or Stream hijacking attacks, it is highly RECOMMENDED that
the DDP Stream be authenticated, integrity protected, and protected the DDP Stream be authenticated, integrity protected, and protected
from replay attacks; it MAY use confidentiality protection to from replay attacks; it MAY use confidentiality protection to
protect from eavesdropping. protect from eavesdropping.
8.4.1 Available Security Services 8.4.1 Available Security Services
IPsec can be used to protect against the packet injection attacks IPsec can be used to protect against the packet injection attacks
outlined above. Because IPsec is designed to secure arbitrary IP outlined above. Because IPsec is designed to secure arbitrary IP
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packet streams, including streams where packets are lost, DDP can packet streams, including streams where packets are lost, DDP can
run on top of IPsec without any change. run on top of IPsec without any change.
DDP security may also profit from SSL or TLS security services DDP security may also profit from SSL or TLS security services
provided for TCP or SCTP based ULPs [TLS] as well as from DTLS provided for TCP or SCTP based ULPs [TLS] as well as from DTLS
[DTLS] security services provided beneath the transport protocol. [DTLS] security services provided beneath the transport protocol.
See [RDMASEC] for further discussion of these approaches and the See [RDMASEC] for further discussion of these approaches and the
rationale for selection of IPsec security services for the RDDP rationale for selection of IPsec security services for the RDDP
protocols. protocols.
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8.4.2 Requirements for IPsec Services for DDP 8.4.2 Requirements for IPsec Services for DDP
IPsec packets are processed (e.g., integrity checked and possibly IPsec packets are processed (e.g., integrity checked and possibly
decrypted) in the order they are received, and a DDP Data Sink will decrypted) in the order they are received, and a DDP Data Sink will
process the decrypted DDP Segments contained in these packets in the process the decrypted DDP Segments contained in these packets in the
same manner as DDP Segments contained in unsecured IP packets. same manner as DDP Segments contained in unsecured IP packets.
The IP Storage working group has defined the normative IPsec The IP Storage working group has defined the normative IPsec
requirements for IP Storage [RFC3723]. Portions of this requirements for IP Storage [RFC3723]. Portions of this
specification are applicable to the DDP. In particular, a compliant specification are applicable to the DDP. In particular, a compliant
skipping to change at line 1453 skipping to change at line 1470
utilized, per-packet data origin authentication, integrity and utilized, per-packet data origin authentication, integrity and
replay protection MUST be used. replay protection MUST be used.
2. It MUST support ESP in tunnel mode and MAY implement ESP in 2. It MUST support ESP in tunnel mode and MAY implement ESP in
transport mode. transport mode.
3. It MUST support IKE [RFC2409] for peer authentication, 3. It MUST support IKE [RFC2409] for peer authentication,
negotiation of security associations, and key management, using negotiation of security associations, and key management, using
the IPsec DOI [RFC2407]. the IPsec DOI [RFC2407].
4. It MUST NOT interpret the receipt of a IKE Phase 2 delete 4. It MUST NOT interpret the receipt of a IKE delete message as a
message as a reason for tearing down the DDP stream. Since reason for tearing down the DDP stream. Since IPsec
IPsec acceleration hardware may only be able to handle a acceleration hardware may only be able to handle a limited
limited number of active IKE Phase 2 SAs, idle SAs may be number of active IPsec Security Associations (SAs), idle SAs
dynamically brought down and a new SA be brought up again, if may be dynamically brought down and a new SA be brought up
activity resumes. again, if activity resumes.
5. It MUST support peer authentication using a pre-shared key, and 5. It MUST support peer authentication using a pre-shared key, and
MAY support certificate-based peer authentication using digital MAY support certificate-based peer authentication using digital
signatures. Peer authentication using the public key encryption signatures. Peer authentication using the public key encryption
methods [RFC2409] SHOULD NOT be used. methods [RFC2409] SHOULD NOT be used.
6. It MUST support IKE Main Mode and SHOULD support Aggressive 6. It MUST support IKE Main Mode and SHOULD support Aggressive
Mode. IKE Main Mode with pre-shared key authentication SHOULD Mode. IKE Main Mode with pre-shared key authentication SHOULD
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NOT be used when either of the peers uses a dynamically NOT be used when either of the peers uses a dynamically
assigned IP address. assigned IP address.
7. Access to locally stored secret information (pre-shared or 7. Access to locally stored secret information (pre-shared or
private key for digital signing) must be suitably restricted, private key for digital signing) must be suitably restricted,
since compromise of the secret information nullifies the since compromise of the secret information nullifies the
security properties of the IKE/IPsec protocols. security properties of the IKE/IPsec protocols.
8. It MUST follow the guidelines of Section 2.3.4 of [RFC3723] on 8. It MUST follow the guidelines of Section 2.3.4 of [RFC3723] on
the setting of IKE parameters to achieve a high level of the setting of IKE parameters to achieve a high level of
interoperability without requiring extensive configuration. interoperability without requiring extensive configuration.
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Furthermore, implementation and deployment of the IPsec services for Furthermore, implementation and deployment of the IPsec services for
DDP should follow the Security Considerations outlined in Section 5 DDP should follow the Security Considerations outlined in Section 5
of [RFC3723]. of [RFC3723].
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9 IANA Considerations 9 IANA Considerations
This document requests no direct action from IANA. The following This document requests no direct action from IANA. The following
consideration is listed here as commentary. consideration is listed here as commentary.
If DDP was enabled a priori for a ULP by connecting to a well-known If DDP was enabled a priori for a ULP by connecting to a well-known
port, this well-known port would be registered for the DDP with port, this well-known port would be registered for the DDP with
IANA. The registration of the well-known port will be the IANA. The registration of the well-known port will be the
responsibility of the ULP specification. responsibility of the ULP specification.
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10 References 10 References
10.1 Normative References 10.1 Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2406] Kent, S. and Atkinson, R., "IP Encapsulating Security [RFC2406] Kent, S. and Atkinson, R., "IP Encapsulating Security
Payload (ESP)", RFC 2406, November 1998. Payload (ESP)", RFC 2406, November 1998.
skipping to change at line 1540 skipping to change at line 1558
[SCTPDDP] C. Bestler and R. Stewart, "Stream Control Transmission [SCTPDDP] C. Bestler and R. Stewart, "Stream Control Transmission
Protocol (SCTP) Direct Data Placement (DDP) Adaptation", Protocol (SCTP) Direct Data Placement (DDP) Adaptation",
Internet Draft draft-ietf-rddp-sctp-04.txt (work in progress), Internet Draft draft-ietf-rddp-sctp-04.txt (work in progress),
June 2006. June 2006.
[TCP] Postel, J., "Transmission Control Protocol", STD 7, RFC 793, [TCP] Postel, J., "Transmission Control Protocol", STD 7, RFC 793,
September 1981. September 1981.
10.2 Informative References 10.2 Informative References
[RFC 4301] S. Kent and K. Seo, "Security Architecture for the
Internet Protocol", RFC 4301, December 2005.
[DTLS] Rescorla, E. and Modadugu, N., "Datagram Transport Layer [DTLS] Rescorla, E. and Modadugu, N., "Datagram Transport Layer
Security", RFC 4347, April 2006. Security", RFC 4347, April 2006.
[IPSEC] Atkinson, R. and Kent, S., "Security Architecture for the [IPSEC] Atkinson, R. and Kent, S., "Security Architecture for the
Internet Protocol", RFC 2401, November 1998. Internet Protocol", RFC 2401, November 1998.
Shah, et. al. Expires March 2007 34
[TLS] Dierks, T. and Rescorla, E., "The Transport Layer Security [TLS] Dierks, T. and Rescorla, E., "The Transport Layer Security
(TLS) Protocol Version 1.1", RFC 4346, April 2006. (TLS) Protocol Version 1.1", RFC 4346, April 2006.
Shah, et. al. Expires January 2007 34 [iSER] M. Ko, et. al., "iSCSI Extensions for RDMA Specification”,
Internet Draft draft-ietf-ips-iser-05.txt (work in progress),
October 2005.
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11 Appendix 11 Appendix
11.1 Receive Window sizing 11.1 Receive Window sizing
This section provides guidance to LLP implementers. This section provides guidance to LLP implementers.
Reliable, sequenced, LLPs include a mechanism to advertise the Reliable, sequenced, LLPs include a mechanism to advertise the
amount of receive buffer space a sender may consume. This is amount of receive buffer space a sender may consume. This is
generally called a "receive window". generally called a "receive window".
skipping to change at line 1586 skipping to change at line 1610
the rate that DDP Segments can be retired; there may be some cases the rate that DDP Segments can be retired; there may be some cases
where segment processing cannot keep up with the incoming packet where segment processing cannot keep up with the incoming packet
rate. If this occurs, one reasonable way to slow the incoming packet rate. If this occurs, one reasonable way to slow the incoming packet
rate is to reduce the receive window. rate is to reduce the receive window.
Note that the LLP should take care to comply with the applicable Note that the LLP should take care to comply with the applicable
RFCs; for instance, for TCP, receivers are highly discouraged from RFCs; for instance, for TCP, receivers are highly discouraged from
"shrinking" the receive window (reducing the right edge of the "shrinking" the receive window (reducing the right edge of the
window after it has been advertised). window after it has been advertised).
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12 Authors' Addresses 12 Authors' Addresses
Hemal Shah Hemal Shah
Broadcom Corporation Broadcom Corporation
16215 Alton Parkway 16215 Alton Parkway
Irvine, CA. USA 92619-7013 Irvine, CA. USA 92619-7013
Phone: 949-926-6941 Phone: 949-926-6941
Email: hemal@broadcom.com Email: hemal@broadcom.com
skipping to change at line 1618 skipping to change at line 1642
Phone: +1 (512) 838-1365 Phone: +1 (512) 838-1365
Email: recio@us.ibm.com Email: recio@us.ibm.com
Paul R. Culley Paul R. Culley
Hewlett-Packard Company Hewlett-Packard Company
20555 SH 249 20555 SH 249
Houston, TX 77070-2698 USA Houston, TX 77070-2698 USA
Phone: +1 (281) 514-5543 Phone: +1 (281) 514-5543
Email: paul.culley@hp.com Email: paul.culley@hp.com
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13 Contributors 13 Contributors
Many thanks to the following individuals for their contributions. Many thanks to the following individuals for their contributions.
John Carrier John Carrier
Adaptec, Inc. Adaptec, Inc.
691 S. Milpitas Blvd. 691 S. Milpitas Blvd.
Milpitas, CA 95035 USA Milpitas, CA 95035 USA
Phone: +1 (360) 378-8526 Phone: +1 (360) 378-8526
skipping to change at line 1672 skipping to change at line 1696
Irvine, CA. USA 92619-7013 Irvine, CA. USA 92619-7013
Phone: +1-949-926-8635 Phone: +1-949-926-8635
email: pthaler@broadcom.com email: pthaler@broadcom.com
Ted Compton Ted Compton
EMC Corporation EMC Corporation
Research Triangle Park, NC 27709, USA Research Triangle Park, NC 27709, USA
Phone: 919-248-6075 Phone: 919-248-6075
Email: compton_ted@emc.com Email: compton_ted@emc.com
Shah, et. al. Expires January 2007 38 Shah, et. al. Expires March 2007 38
Jim Wendt Jim Wendt
Hewlett-Packard Company Hewlett-Packard Company
8000 Foothills Boulevard 8000 Foothills Boulevard
Roseville, CA 95747-5668 USA Roseville, CA 95747-5668 USA
Phone: +1 (916) 785-5198 Phone: +1 (916) 785-5198
Email: jim_wendt@hp.com Email: jim_wendt@hp.com
Mike Krause Mike Krause
Hewlett-Packard Company, 43LN Hewlett-Packard Company, 43LN
19410 Homestead Road 19410 Homestead Road
skipping to change at line 1727 skipping to change at line 1751
Dave Garcia Dave Garcia
Hewlett-Packard Company Hewlett-Packard Company
19333 Vallco Parkway 19333 Vallco Parkway
Cupertino, Ca. 95014 USA Cupertino, Ca. 95014 USA
Phone: +1 (408) 285-6116 Phone: +1 (408) 285-6116
Email: dave.garcia@hp.com Email: dave.garcia@hp.com
Jeff Hilland Jeff Hilland
Hewlett-Packard Company Hewlett-Packard Company
Shah, et. al. Expires January 2007 39 Shah, et. al. Expires March 2007 39
20555 SH 249 20555 SH 249
Houston, Tx. 77070-2698 USA Houston, Tx. 77070-2698 USA
Phone: +1 (281) 514-9489 Phone: +1 (281) 514-9489
Email: jeff.hilland@hp.com Email: jeff.hilland@hp.com
Barry Reinhold Barry Reinhold
Lamprey Networks Lamprey Networks
Durham, NH 03824 USA Durham, NH 03824 USA
Phone: +1 (603) 868-8411 Phone: +1 (603) 868-8411
Email: bbr@LampreyNetworks.com Email: bbr@LampreyNetworks.com
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14 Intellectual Property Statement 14 Intellectual Property Statement
The IETF takes no position regarding the validity or scope of any The IETF takes no position regarding the validity or scope of any
Intellectual Property Rights or other rights that might be claimed Intellectual Property Rights or other rights that might be claimed
to pertain to the implementation or use of the technology described to pertain to the implementation or use of the technology described
in this document or the extent to which any license under such in this document or the extent to which any license under such
rights might or might not be available; nor does it represent that rights might or might not be available; nor does it represent that
it has made any independent effort to identify any such rights. it has made any independent effort to identify any such rights.
Information on the procedures with respect to rights in RFC Information on the procedures with respect to rights in RFC
skipping to change at line 1765 skipping to change at line 1789
of such proprietary rights by implementers or users of this of such proprietary rights by implementers or users of this
specification can be obtained from the IETF on-line IPR repository specification can be obtained from the IETF on-line IPR repository
at http://www.ietf.org/ipr. at http://www.ietf.org/ipr.
The IETF invites any interested party to bring to its attention any The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary copyrights, patents or patent applications, or other proprietary
rights that may cover technology that may be required to implement rights that may cover technology that may be required to implement
this standard. Please address the information to the IETF at ietf- this standard. Please address the information to the IETF at ietf-
ipr@ietf.org. ipr@ietf.org.
Shah, et. al. Expires January 2007 41 Shah, et. al. Expires March 2007 41
15 Copyright Notice 15 Copyright Notice
Copyright (C) The Internet Society (2006). Copyright (C) The Internet Society (2006).
This document is subject to the rights, licenses and restrictions This document is subject to the rights, licenses and restrictions
contained in BCP 78, and except as set forth therein, the authors contained in BCP 78, and except as set forth therein, the authors
retain all their rights. retain all their rights.
This document and the information contained herein are provided on This document and the information contained herein are provided on
an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE
REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE
INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF
THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
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