draft-ietf-dhc-dhcpv4-bulk-leasequery-04.txt   draft-ietf-dhc-dhcpv4-bulk-leasequery-05.txt 
DHC Working Group Kim Kinnear DHC Working Group Kim Kinnear
Internet Draft Bernie Volz Internet Draft Bernie Volz
Intended Status: Standards Track Mark Stapp Intended Status: Standards Track Mark Stapp
Expires: October 28, 2011 Cisco Systems, Inc. Expires: May 18, 2012 Cisco Systems, Inc.
D. Rao D. Rao
B. Joshi B. Joshi
Infosys Technologies Ltd. Infosys Technologies Ltd.
Neil Russell Neil Russell
Nokia Nokia
P. Kurapati P. Kurapati
Juniper Networks Ltd. Juniper Networks Ltd.
April 28, 2011 November 18, 2011
Bulk DHCPv4 Lease Query Bulk DHCPv4 Lease Query
<draft-ietf-dhc-dhcpv4-bulk-leasequery-04.txt> <draft-ietf-dhc-dhcpv4-bulk-leasequery-05.txt>
Status of this Memo Status of this Memo
This Internet-Draft is submitted to IETF in full conformance with the This Internet-Draft is submitted to IETF in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet- other groups may also distribute working documents as Internet-
Drafts. Drafts.
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7.7. Multiple Queries to a Single Server over One Connection.... 26 7.7. Multiple Queries to a Single Server over One Connection.... 26
7.8. Closing Connections........................................ 27 7.8. Closing Connections........................................ 27
8. Server Behavior.............................................. 27 8. Server Behavior.............................................. 27
8.1. Accepting Connections...................................... 27 8.1. Accepting Connections...................................... 27
8.2. Replying to a Bulk Leasequery.............................. 28 8.2. Replying to a Bulk Leasequery.............................. 28
8.3. Building a Single Reply for Bulk Leasequery................ 31 8.3. Building a Single Reply for Bulk Leasequery................ 31
8.4. Multiple or Parallel Queries............................... 32 8.4. Multiple or Parallel Queries............................... 32
8.5. Closing Connections........................................ 33 8.5. Closing Connections........................................ 33
9. Security Considerations...................................... 33 9. Security Considerations...................................... 33
10. IANA Considerations......................................... 34 10. IANA Considerations......................................... 34
11. Acknowledgements............................................ 35 11. Acknowledgements............................................ 36
12. References.................................................. 36 12. References.................................................. 36
12.1. Normative References...................................... 36 12.1. Normative References...................................... 36
12.2. Informative References.................................... 36 12.2. Informative References.................................... 37
1. Introduction 1. Introduction
The DHCPv4 protocol [RFC2131] [RFC2132] specifies a mechanism for the The DHCPv4 protocol [RFC2131] [RFC2132] specifies a mechanism for the
assignment of IPv4 address and configuration information to IPv4 assignment of IPv4 address and configuration information to IPv4
nodes. DHCPv4 servers maintain authoritative binding information. nodes. DHCPv4 servers maintain authoritative binding information.
+--------+ +--------+
| DHCPv4 | +--------------+ | DHCPv4 | +--------------+
| Server |-...-| DSLAM | | Server |-...-| DSLAM |
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systems run NTP, the clock skew is negligible, and this is not systems run NTP, the clock skew is negligible, and this is not
only acceptable, but desired. only acceptable, but desired.
While it is easy to think that this can be calculated precisely While it is easy to think that this can be calculated precisely
after one message is received by a requestor from a DHCPv4 after one message is received by a requestor from a DHCPv4
server, a more accurate value is derived from continuously server, a more accurate value is derived from continuously
examining the instantaneous value developed from each message examining the instantaneous value developed from each message
received from a DHCPv4 server and using it to make small received from a DHCPv4 server and using it to make small
adjustments to the existing value held in the requestor. adjustments to the existing value held in the requestor.
o "Default VPN"
Indicates that the address being described belongs to the set of
addresses not part of any VPN. In other words, the normal
address space operated on by DHCP. This includes private
addresses, for example the 10.x.x.x addresses as well as the
other private subnets that are not routed on the open internet.
o "DHCPv4 client" o "DHCPv4 client"
A DHCPv4 client is an Internet node using DHCPv4 to obtain A DHCPv4 client is an Internet node using DHCPv4 to obtain
configuration parameters such as a network address. configuration parameters such as a network address.
o "DHCPv4 relay agent" o "DHCPv4 relay agent"
A DHCPv4 relay agent is a third-party agent that transfers BOOTP A DHCPv4 relay agent is a third-party agent that transfers BOOTP
and DHCPv4 messages between clients and servers residing on and DHCPv4 messages between clients and servers residing on
different subnets, per [RFC951] and [RFC1542]. different subnets, per [RFC951] and [RFC1542].
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A DHCPv4 relay agent is a third-party agent that transfers BOOTP A DHCPv4 relay agent is a third-party agent that transfers BOOTP
and DHCPv4 messages between clients and servers residing on and DHCPv4 messages between clients and servers residing on
different subnets, per [RFC951] and [RFC1542]. different subnets, per [RFC951] and [RFC1542].
o "DHCPv4 server" o "DHCPv4 server"
A DHCPv4 server is an Internet node that returns configuration A DHCPv4 server is an Internet node that returns configuration
parameters to DHCPv4 clients. parameters to DHCPv4 clients.
o "DSLAM" o "DSLAM"
Digital Subscriber Line Multiplexer. Digital Subscriber Line Multiplexer.
o "downstream" o "downstream"
Refers to a direction away from the central part of a network Refers to a direction away from the central part of a network
and toward the edge. In a DHCPv4 context, typically refers to a and toward the edge. In a DHCPv4 context, typically refers to a
network direction which is away from the DHCPv4 server. network direction which is away from the DHCPv4 server.
o "Global VPN"
Another name for the "Default VPN".
o "IP address" o "IP address"
In this document, the term "IP address" refers to an IPv4 IP In this document, the term "IP address" refers to an IPv4 IP
address. address.
o "IP address binding" o "IP address binding"
The information that a DHCPv4 server keeps regarding the The information that a DHCPv4 server keeps regarding the
relationship between a DHCPv4 client and an IP address. This relationship between a DHCPv4 client and an IP address. This
includes the identity of the DHCPv4 client and the expiration includes the identity of the DHCPv4 client and the expiration
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Any of the above queries can be qualified by the specification of a Any of the above queries can be qualified by the specification of a
query-start-time or a query-end-time (or both). When these timers are query-start-time or a query-end-time (or both). When these timers are
used as qualifiers, they indicate that a binding should be included used as qualifiers, they indicate that a binding should be included
if it changed on or after the query-start-time and on or before the if it changed on or after the query-start-time and on or before the
query-end-time. query-end-time.
In addition, any of the above queries can be qualified by the In addition, any of the above queries can be qualified by the
specification of a vpn-id option [VpnId] to select the VPN on which specification of a vpn-id option [VpnId] to select the VPN on which
the query should be processed. The vpn-id option is also extended to the query should be processed. The vpn-id option is also extended to
allow queries across all available VPNs. By default, only the default allow queries across all available VPNs. In the absence of any vpn-id
VPN is used to satisfy the query. option, only the default (global) VPN is used to satisfy the query.
5. Interaction Between UDP Leasequery and Bulk Leasequery 5. Interaction Between UDP Leasequery and Bulk Leasequery
Bulk Leasequery can be seen as an extension of the existing UDP Bulk Leasequery can be seen as an extension of the existing UDP
Leasequery protocol [RFC4388]. This section clarifies the Leasequery protocol [RFC4388]. This section clarifies the
relationship between the two protocols. relationship between the two protocols.
Only the DHCPBULKLEASEQUERY request is supported over the Bulk Only the DHCPBULKLEASEQUERY request is supported over the Bulk
Leasequery connection. No other DHCPv4 requests are supported. The Leasequery connection. No other DHCPv4 requests are supported. The
Bulk Leasequery connection is not an alternative DHCPv4 communication Bulk Leasequery connection is not an alternative DHCPv4 communication
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The code for this option is TBD1. The length of this option is a The code for this option is TBD1. The length of this option is a
minimum of 1 octet. minimum of 1 octet.
Status Status Status Status
Code Len Code Message Code Len Code Message
+------+------+------+------+------+-- --+-----+ +------+------+------+------+------+-- --+-----+
| TBD1 | n+1 |status| s1 | s2 | ... | sn | | TBD1 | n+1 |status| s1 | s2 | ... | sn |
+------+------+------+------+------+-- --+-----+ +------+------+------+------+------+-- --+-----+
The status-code is an octet defined in the table below. The Status The status-code is an octet defined in the table below. The Status
Message is an optional NVT ASCII encoded text string suitable for Message is an optional UTF-8 encoded text string suitable for display
display to an end user, which MUST NOT be null-terminated. to an end user, which MUST NOT be null-terminated.
Name Status Code Description Name Status Code Description
---- ----------- ----------- ---- ----------- -----------
Success 000 Success. Also signaled by absence of Success 000 Success. Also signaled by absence of
a status-code option. a status-code option.
UnspecFail 001 Failure, reason unspecified. UnspecFail 001 Failure, reason unspecified.
QueryTerminated 002 Indicates that the server is unable to QueryTerminated 002 Indicates that the server is unable to
perform a query or has prematurely terminated perform a query or has prematurely terminated
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MBZ: MUST BE ZERO (reserved for future use) MBZ: MUST BE ZERO (reserved for future use)
The REMOTE flag is used to indicate where the most recent change of The REMOTE flag is used to indicate where the most recent change of
state (or other interesting change) concerning this IPv4 address took state (or other interesting change) concerning this IPv4 address took
place. If the value is local, then the change took place on the place. If the value is local, then the change took place on the
server from which this message was transmitted. If the value is server from which this message was transmitted. If the value is
remote, then the change took place on some other server, and was made remote, then the change took place on some other server, and was made
known to the server from which this message was transmitted. known to the server from which this message was transmitted.
If this option was requested and it doesn't appear, the requestor If this option was requested and it doesn't appear, the requestor
SHOULD consider that the data-source was local. MUST consider that the data-source was local.
6.2.9. Virtual Subnet Selection Type and Information 6.2.9. Virtual Subnet Selection Type and Information
All of the (sub)options defined in [VpnId] carry identical payloads, All of the (sub)options defined in [VpnId] carry identical payloads,
consisting of a type and additional VSS (Virtual Subnet Selection) consisting of a type and additional VSS (Virtual Subnet Selection)
information. The existing table is extended (see below) with a new information. The existing table is extended (see below) with a new
type 254 to allow specification of a type code which indicates that type 254 to allow specification of a type code which indicates that
all VPN's are to be used to process the Bulk Leasequery. all VPN's are to be used to process the Bulk Leasequery.
Type VSS Information format: Type VSS Information format:
---- ----------------------- ---- -----------------------
0 NVT ASCII VPN identifier 0 UTF-8 ASCII VPN identifier
1 RFC 2685 VPN-ID 1 RFC 2685 VPN-ID
CHANGED -> 2-253 Not Allowed CHANGED -> 2-253 Not Allowed
NEW -> 254 All VPN's (wildcard) NEW -> 254 All VPN's (wildcard)
255 Global, default VPN 255 Global, default VPN
6.3. Connection and Transmission Parameters 6.3. Connection and Transmission Parameters
DHCPv4 servers that support Bulk Leasequery SHOULD listen for DHCPv4 servers that support Bulk Leasequery SHOULD listen for
incoming TCP connections on the DHCPv4 server port 67. incoming TCP connections on the DHCPv4 server port 67.
Implementations MAY offer to make the incoming port configurable, but Implementations MAY offer to make the incoming port configurable, but
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o Query End Time o Query End Time
Inclusion of a query-end-time option specifies that only IP address Inclusion of a query-end-time option specifies that only IP address
bindings which have changed on or before the time specified in the bindings which have changed on or before the time specified in the
query-end-time option should be returned. query-end-time option should be returned.
o VPN Id o VPN Id
If no vpn-id option appears in the DHCPBULKLEASEQUERY, the default If no vpn-id option appears in the DHCPBULKLEASEQUERY, the default
VPN is used to search to satisfy the query specified by the (global) VPN is searched to satisfy the query specified by the
DHCPBULKLEASEQUERY. Using the vpn-id option [VpnId] allows the DHCPBULKLEASEQUERY. Using the vpn-id option [VpnId] allows the
requestor to specify a single VPN other than the default VPN. In requestor to specify a single VPN other than the default VPN. In
addition, the vpn-id option has been extended as part of this addition, the vpn-id option has been extended as part of this
document to allow specification that all configured VPN's be document to allow specification that all configured VPN's be
searched in order to satisfy the query specified in the searched in order to satisfy the query specified in the
DHCPBULKLEASEQUERY. DHCPBULKLEASEQUERY.
In all cases, any message returned from a DHCPBULKLEASEQUERY In all cases, any message returned from a DHCPBULKLEASEQUERY
request containing information about an IP address for other than request containing information about an IP address for other than
the default VPN MUST contain a vpn-id option in the message. the default (global) VPN MUST contain a vpn-id option in the
message.
Use of the query-start-time or the query-end-time options or both can Use of the query-start-time or the query-end-time options or both can
serve to reduce the amount of data transferred over the TCP serve to reduce the amount of data transferred over the TCP
connection by a considerable amount. connection by a considerable amount.
The TCP connection may become blocked or stop being writable while The TCP connection may become blocked or stop being writable while
the requestor is sending its query. Should this happen, the the requestor is sending its query. Should this happen, the
implementation's behavior is controlled by the current value of implementation's behavior is controlled by the current value of
BULK_LQ_DATA_TIMEOUT. The default value is given elsewhere in this BULK_LQ_DATA_TIMEOUT. The default value is given elsewhere in this
document, and this value may be overridden by local configuration of document, and this value may be overridden by local configuration of
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o Query End Time o Query End Time
If a query-end-time option appears in the DHCPBULKLEASEQUERY If a query-end-time option appears in the DHCPBULKLEASEQUERY
request, only IP address bindings that have changed on or before request, only IP address bindings that have changed on or before
the time specified in the query-end-time option should be returned. the time specified in the query-end-time option should be returned.
o VPN Id o VPN Id
If no vpn-id option appears in the DHCPBULKLEASEQUERY, the default If no vpn-id option appears in the DHCPBULKLEASEQUERY, the default
VPN is used to satisfy the query. A vpn-id option [VpnId] value (global) VPN is used to satisfy the query. A vpn-id option [VpnId]
other than the wildcard value (254) allows the requestor to specify value other than the wildcard value (254) allows the requestor to
a single VPN other than the default VPN. In addition, the vpn-id specify a single VPN other than the default VPN. In addition, the
option has been extended as part of this document to allow vpn-id option has been extended as part of this document to allow
specification of a type 254 which indicates that all configured specification of a type 254 which indicates that all configured
VPN's be searched in order to satisfy the primary query. VPN's be searched in order to satisfy the primary query.
In all cases, if the information returned in a DHCPLEASEACTIVE or In all cases, if the information returned in a DHCPLEASEACTIVE or
DHCPLEASEUNASSIGNED message is for a VPN other than the default, a DHCPLEASEUNASSIGNED message is for a VPN other than the default
vpn-id option MUST appear in the packet. (global) VPN, a vpn-id option MUST appear in the packet.
The query-start-time and query-end-time qualifiers are used to The query-start-time and query-end-time qualifiers are used to
constrain the amount of data returned by a Bulk Leasequery request by constrain the amount of data returned by a Bulk Leasequery request by
returning only IP addresses whose address bindings have changed in returning only IP addresses whose address bindings have changed in
some way during the time window specified by the query-start-time and some way during the time window specified by the query-start-time and
query-end-time. query-end-time.
A DHCPv4 server SHOULD consider an address binding to have changed A DHCPv4 server SHOULD consider an address binding to have changed
during a specified time window if either the client-last- during a specified time window if either the client-last-
transaction-time or the start-time-of-state of the address binding transaction-time or the start-time-of-state of the address binding
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in-process queries from any one connection, and that they limit the in-process queries from any one connection, and that they limit the
period of time during which an idle connection will be left open. period of time during which an idle connection will be left open.
[RFC4388] discusses security concerns and potential solutions for [RFC4388] discusses security concerns and potential solutions for
DHCPLEASEQUERY message exchanges in its Section 7, and all of the DHCPLEASEQUERY message exchanges in its Section 7, and all of the
solutions discussed there are applicable to the DHCPLEASEQUERY solutions discussed there are applicable to the DHCPLEASEQUERY
message exchanges described in this document. message exchanges described in this document.
10. IANA Considerations 10. IANA Considerations
This document defines two new name spaces associated with DHCPv4 IANA is requested to assign the following new DHCPv4 option codes
options: from the registry "BOOTP Vendor Extensions and DHCP Options"
maintained at http://www.iana.org/assignments/bootp-dhcp-parameters
1. Status code values for the status-code option, TBD1.
2. DHCP state values for the dhcp-state option, TBD6. 1. An option code of TBD1 for status-code.
IANA has established a registry of values for these two name spaces. 2. An option code of TBD2 for base-time.
These name spaces will be managed by IANA. New values for these name
spaces may only be defined by IETF Consensus, as described in
[RFC5226]. Basically, this means that they are defined by RFCs
approved by the IESG.
IANA is requested to assign the following new values for this 3. An option code of TBD3 for start-time-of-state.
document. See Section 6.2 for details.
1. A dhcp-message-type of TBD8 for DHCPBULKLEASEQUERY. 4. An option code of TBD4 for query-start-time.
2. A dhcp-message-type of TBD9 for DHCPLEASEQUERYDONE. 5. An option code of TBD5 for query-end-time.
3. An option code of TBD1 for status-code. 6. An option code of TBD6 for dhcp-state.
4. An option code of TBD2 for base-time. 7. An option code of TBD7 for data-source.
5. An option code of TBD3 for start-time-of-state. IANA is requested to assign the following new DHCP message types from
the registry "DHCP Message Type 53 Values" maintained at
http://www.iana.org/assignments/bootp-dhcp-parameters
6. An option code of TBD4 for query-start-time. 1. A dhcp-message-type of TBD8 for DHCPBULKLEASEQUERY.
7. An option code of TBD5 for query-end-time. 2. A dhcp-message-type of TBD9 for DHCPLEASEQUERYDONE.
8. An option code of TBD6 for dhcp-state. IANA is requested to create a new registry on the same assignments
page, titled "DHCP State TBD6 Values" (where TBD6 corresponds to the
assigned value of the dhcp-state option, above). This registry will
have the following initial values:
9. An option code of TBD7 for data-source. State
-----
1 AVAILABLE
2 ACTIVE
3 EXPIRED
4 RELEASED
5 ABANDONED
6 RESET
7 REMOTE
8 TRANSITIONING
10.Values for status code in a status-code option (option TBD1): New values for this name space may only be defined by IETF Consensus,
as described in [RFC5226]. Basically, this means that they are
defined by RFCs approved by the IESG.
Name status-code IANA is requested to create a new registry on the same assignments
---- ----------- page, titled "DHCP Status Code TBD1 Values" (where TBD1 corresponds
Success 000 to the assigned value of the status-code option, above). This
UnspecFail 001 registry will have the following initial values:
QueryTerminated 002
MalformedQuery 003
NotAllowed 004
11.Values for dhcp-state (option TBD6): Name status-code
---- -----------
Success 000
UnspecFail 001
QueryTerminated 002
MalformedQuery 003
NotAllowed 004
State New values for this name space may only be defined by IETF Consensus,
----- as described in [RFC5226]. Basically, this means that they are
1 AVAILABLE defined by RFCs approved by the IESG.
2 ACTIVE
3 EXPIRED
4 RELEASED
5 ABANDONED
6 RESET
7 REMOTE
8 TRANSITIONING
12.Additional type field values for the Virtual Subnet Selection Type IANA is requested to revise the registry that will be created on the
and Information [VpnId]: same assignments page when the [VpnId] option is approved. The
registry will be "Virtual Subnet Selection Type and Information". It
should be revised to appear as follows:
Type VSS Information format: Type VSS Information format:
0 NVT ASCII VPN identifier 0 UTF-8 ASCII VPN identifier
1 RFC2685 VPN-ID 1 RFC2685 VPN-ID
2-253 Not Allowed 2-253 Not Allowed
254 All VPN's. (wildcard; only allowed in 254 All VPN's. (wildcard; only allowed in
DHCPBULKLEASEQUERY messages) DHCPBULKLEASEQUERY messages)
255 Global, default VPN. 255 Global, default VPN.
11. Acknowledgements 11. Acknowledgements
This draft is a collaboration between the authors of draft-dtv-dhc- This draft is a collaboration between the authors of draft-dtv-dhc-
dhcpv4-bulk-leasequery-00.txt and draft-kkinnear-dhc-dhcpv4-bulk- dhcpv4-bulk-leasequery-00.txt and draft-kkinnear-dhc-dhcpv4-bulk-
leasequery-00.txt. Both documents acknowledged that significant text leasequery-00.txt. Both documents acknowledged that significant text
as well as important ideas were borrowed in whole or in part from the as well as important ideas were borrowed in whole or in part from the
DHCPv6 Bulk Leasequery RFC, [RFC5460] written by Mark Stapp. Further DHCPv6 Bulk Leasequery RFC, [RFC5460] written by Mark Stapp. Further
suggestions and improvements were made by participants in the DHC suggestions and improvements were made by participants in the DHC
working group, including Alfred Hoenes. working group, including Alfred Hoenes.
skipping to change at page 36, line 28 skipping to change at page 36, line 47
[RFC3046] Patrick, M., "DHCP Relay Agent Information Option", RFC [RFC3046] Patrick, M., "DHCP Relay Agent Information Option", RFC
3046, January 2001. 3046, January 2001.
[RFC4388] Woundy, R., K. Kinnear, "Dynamic Host Configuration [RFC4388] Woundy, R., K. Kinnear, "Dynamic Host Configuration
Protocol (DHCP) Leasequery", RFC 4388, February 2006. Protocol (DHCP) Leasequery", RFC 4388, February 2006.
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an [RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", BCP 26, RFC 5226, May 2008. IANA Considerations Section in RFCs", BCP 26, RFC 5226, May 2008.
[RelayId] Stapp, M., "The DHCPv4 Relay Agent Identifier Suboption", [RelayId] Stapp, M., "The DHCPv4 Relay Agent Identifier Suboption",
draft-ietf-dhc-relay-id-suboption-07.txt, (work in progress) July draft-ietf-dhc-relay-id-suboption-09.txt, (work in progress) June
2009. 2011.
[VpnId] Kinnear, K., R. Johnson, M. Stapp and J. Kumarasamy, "Virtual [VpnId] Kinnear, K., R. Johnson, M. Stapp and J. Kumarasamy, "Virtual
Subnet Selection Options for DHCPv4 and DHCPv6" draft-ietf-dhc- Subnet Selection Options for DHCPv4 and DHCPv6" draft-ietf-dhc-
vpn-option-13.txt, (work in progress) April 2011. vpn-option-14.txt, (work in progress) November 2011.
12.2. Informative References 12.2. Informative References
[RFC951] Croft, B., Gilmore, J., "Bootstrap Protocol (BOOTP)", RFC [RFC951] Croft, B., Gilmore, J., "Bootstrap Protocol (BOOTP)", RFC
951, September 1985. 951, September 1985.
[RFC1542] Wimer, W., "Clarifications and Extensions for the Bootstrap [RFC1542] Wimer, W., "Clarifications and Extensions for the Bootstrap
Protocol", RFC 1542, October 1993. Protocol", RFC 1542, October 1993.
[RFC4614] Duke, M., R. Braden, W. Eddy, and E. Blanton, "A Roadmap [RFC4614] Duke, M., R. Braden, W. Eddy, and E. Blanton, "A Roadmap
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