draft-ietf-msec-arch-04.txt   draft-ietf-msec-arch-05.txt 
Internet Engineering Task Force Thomas Hardjono (VeriSign) Internet Engineering Task Force Thomas Hardjono (VeriSign)
INTERNET-DRAFT Brian Weis (Cisco) INTERNET-DRAFT Brian Weis (Cisco)
draft-ietf-msec-arch-04.txt Expires May 2004 draft-ietf-msec-arch-05.txt Expires July 2004
November 2003 January 2004
The Multicast Security Architecture The Multicast Group Security Architecture
Status of this Memo Status of this Memo
This document is an Internet-Draft and is in full conformance This document is an Internet-Draft and is in full conformance
with all provisions of Section 10 of RFC2026. with all provisions of Section 10 of RFC2026.
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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months and may be updated, replaced, or obsoleted by other months and may be updated, replaced, or obsoleted by other
documents at any time. It is inappropriate to use Internet- documents at any time. It is inappropriate to use Internet-
Drafts as reference material or to cite them other than as Drafts as reference material or to cite them other than as
"work in progress." "work in progress."
The list of current Internet-Drafts can be accessed at The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt http://www.ietf.org/ietf/1id-abstracts.txt
The list of Internet-Draft Shadow Directories can be accessed at The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html. http://www.ietf.org/shadow.html.
Copyright Notice
Copyright (C) The Internet Society (2004). All Rights Reserved.
Abstract Abstract
This document provides an overview and rationale of the multicast This document provides an overview and rationale of the multicast
security architecture used for large multicast groups. The document security architecture used to secure data packets of large multicast
begins by introducing a Multicast Security Reference Framework, and groups. The document begins by introducing a Multicast Security
proceeds to identify the security services that may be part of a Reference Framework, and proceeds to identify the security services
secure multicast solution. that may be part of a secure multicast solution.
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Table of Contents Table of Contents
1. Introduction.......................................................2 1. Introduction.......................................................2
1.1 Scope...........................................................3 1.1 Scope...........................................................3
1.2 Summary of Contents of Document.................................3 1.2 Summary of Contents of Document.................................4
1.3 Audience........................................................4 1.3 Audience........................................................4
1.4 Terminology.....................................................4 1.4 Terminology.....................................................4
2. Architectural Design: The Multicast Security Reference Framework...5 2. Architectural Design: The Multicast Security Reference Framework...5
2.1 The Reference Framework.........................................5 2.1 The Reference Framework.........................................5
2.2 Elements of the Centralized Reference Framework.................6 2.2 Elements of the Centralized Reference Framework.................6
2.2.1 Group Controller and Key Server.............................7 2.2.1 Group Controller and Key Server.............................7
2.2.2 Sender and Receiver.........................................7 2.2.2 Sender and Receiver.........................................7
2.2.3 Policy Server...............................................7 2.2.3 Policy Server...............................................7
2.3 Elements of the Distributed Reference Framework.................8 2.3 Elements of the Distributed Reference Framework.................8
3. Functional Areas...................................................9 3. Functional Areas...................................................9
3.1 Multicast Data Handling.........................................9 3.1 Multicast Data Handling.........................................9
3.2 Group Key Management...........................................10 3.2 Group Key Management...........................................10
3.3 Multicast Security Policies....................................11 3.3 Multicast Security Policies....................................11
4. Group Security Associations (GSA).................................12 4. Group Security Associations (GSA).................................12
4.1 The Security Association.......................................12 4.1 The Security Association.......................................12
4.2 Structure of a GSA: Introduction...............................12 4.2 Structure of a GSA: Introduction...............................12
4.3 Structure of a GSA: Reasoning..................................13 4.3 Structure of a GSA: Reasoning..................................13
4.4 Definition of GSA..............................................14 4.4 Definition of GSA..............................................14
4.5 Typical Compositions of a GSA..................................16 4.5 Typical Compositions of a GSA..................................16
5. Security Services.................................................17 5. Security Services.................................................16
5.1 Multicast Data Confidentiality.................................17 5.1 Multicast Data Confidentiality.................................17
5.2 Multicast Source Authentication and Data Integrity.............18 5.2 Multicast Source Authentication and Data Integrity.............17
5.3 Multicast Group Authentication.................................18 5.3 Multicast Group Authentication.................................18
5.4 Multicast Group Membership Management..........................19 5.4 Multicast Group Membership Management..........................18
5.5 Multicast Key Management.......................................19 5.5 Multicast Key Management.......................................19
5.6 Multicast Policy Management....................................20 5.6 Multicast Policy Management....................................20
6. Security Considerations...........................................21 6. Security Considerations...........................................20
6.1 Multicast Data Handling........................................21 6.1 Multicast Data Handling........................................20
6.2 Group Key Management...........................................21 6.2 Group Key Management...........................................21
6.3 Multicast Security Policies....................................21 6.3 Multicast Security Policies....................................21
7. Acknowledgments...................................................21 7. Intellectual Property Rights Statement............................21
8. References........................................................22 8. Acknowledgments...................................................21
8.1 Normative References...........................................22 9. References........................................................22
8.2 Informative References.........................................22 9.1 Normative References...........................................22
9.2 Informative References.........................................22
Authors Addresses....................................................24 Authors Addresses....................................................24
Full Copyright Statement.............................................24
1. Introduction 1. Introduction
Securing IP multicast communication is a complex task that involves Hardjono, Weis Expires July, 2004 2
many aspects. Consequently, a secure IP multicast protocol suite must The Multicast Group Security Architecture January, 2004
have a number of functional areas that address different aspects of
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the solution. This document describes those functional areas, and how Securing IP multicast group communication is a complex task that
they are related. involves many aspects. Consequently, a secure IP multicast protocol
suite must have a number of functional areas that address different
aspects of the solution. This document describes those functional
areas, and how they are related.
1.1 Scope 1.1 Scope
This architecture is concerned with the securing of large multicast This architecture is concerned with the securing of large multicast
groups. Whereas it can also be used for smaller groups, it is not groups. Whereas it can also be used for smaller groups, it is not
necessarily the most efficient means. Other architectures (e.g., the necessarily the most efficient means. Other architectures (e.g., the
Cliques architecture [STW]) can be more efficient for small ad-hoc Cliques architecture [STW]) can be more efficient for small ad-hoc
group communication. group communication.
This architecture is "end to end", and does not require multicast This architecture is "end to end", and does not require multicast
routing protocols (e.g., PIM [RFC2362]) to participate in this routing protocols (e.g., PIM [RFC2362]) to participate in this
architecture. Inappropriate routing may cause denial of service to architecture. Inappropriate routing may cause denial of service to
application layer groups conforming to this architecture. However the application layer groups conforming to this architecture. However the
routing cannot affect the authenticity or secrecy of group data or routing cannot affect the authenticity or secrecy of group data or
management packets. The multicast routing protocols could themselves management packets. The multicast routing protocols could themselves
use this architecture to protect their own multicast and group use this architecture to protect their own multicast and group
packets. However, this would be independent of any secure application packets. However, this would be independent of any secure application
layer group. layer group.
This architecture does not require IP multicast admission control This architecture does not require IP multicast admission control
protocols (e.g., IGMP [RFC3376], MLD [RFC3019]) to participate in protocols (e.g., IGMP [RFC3376], MLD [RFC3019]) to be a part of
this architecture. As such, a "join" or "leave" operation for a secure multicast groups. As such, a "join" or "leave" operation for a
secure group is independent of a "join" or "leave" of an IP multicast secure group is independent of a "join" or "leave" of an IP multicast
group. For example, the process of joining a secure group requires group. For example, the process of joining a secure group requires
being authenticated and authorized by a security device, while the being authenticated and authorized by a security device, while the
process of joining an IP multicast group entails contacting a process of joining an IP multicast group entails contacting a
multicast-aware router. Admission control protocols could themselves multicast-aware router. Admission control protocols could themselves
use this architecture to protect their own multicast packets. use this architecture to protect their own multicast packets.
However, this would be independent of any secure application layer However, this would be independent of any secure application layer
group. group.
This architecture does not explicitly describe how secure multicast This architecture does not explicitly describe how secure multicast
groups deal with Network Address Translation (NAT) [RFC2663]. groups deal with Network Address Translation (NAT) [RFC2663].
Generally speaking, NAT is not a problem with IP multicast traffic. Multicast routing protocols generally require the source and
This is true because multicast routing protocols generally require destination addresses and ports of an IP multicast packet to remain
the source of an IP multicast packet to remain unchanged in order to unchanged. This allows consistent multicast distribution trees to be
create distribution trees. However, if NAT is deployed in a network created throughout the network. If NAT is used in a network, then the
for IP multicast packets (e.g., between administrative entities), connectivity of senders and receivers may be adversely affected. This
then the connectivity of senders and receivers may be adversely situation is neither improved or degraded as a result of deploying
affected. this architecture.
This architecture does not require the use of reliable mechanisms, This architecture does not require the use of reliable mechanisms,
for either data or management protocols. The use of reliable for either data or management protocols. The use of reliable
multicast routing techniques (e.g., FEC [RFC3453]) enhance the multicast routing techniques (e.g., FEC [RFC3453]) enhance the
availability of secure multicast groups. However the authenticity or availability of secure multicast groups. However the authenticity or
secrecy of group data or management packets is not affected by the secrecy of group data or management packets is not affected by the
omission of that capability from a deployment. omission of that capability from a deployment.
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This document provides an architectural overview that outlines the This document provides an architectural overview that outlines the
security services required to secure large multicast groups. It security services required to secure large multicast groups. It
provides a Reference Framework for organizing the various elements provides a Reference Framework for organizing the various elements
within the architecture, and explains the elements of the Reference within the architecture, and explains the elements of the Reference
Framework. Framework.
The Reference Framework organizes the elements of the architecture The Reference Framework organizes the elements of the architecture
along three Functional Areas pertaining to security. These elements along three Functional Areas pertaining to security. These elements
cover the treatment of data when it is to be sent to a group, the cover the treatment of data when it is to be sent to a group, the
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multicast counterpart of the unicast Security Association (SA). The multicast counterpart of the unicast Security Association (SA). The
GSA is specific to multicast security, and is the foundation of the GSA is specific to multicast security, and is the foundation of the
work on group key management. work on group key management.
1.3 Audience 1.3 Audience
This document is addressed to the technical community, implementers This document is addressed to the technical community, implementers
of IP multicast security technology, and others interested in gaining of IP multicast security technology, and others interested in gaining
a general background understanding of multicast security. This a general background understanding of multicast security. This
document assumes that the reader is familiar with the Internet document assumes that the reader is familiar with the Internet
Protocol, the IPsec suite of protocols (e.g. IPsec [RFC2401], IKE Protocol, the IPsec suite of protocols (e.g. [RFC2401]), related
[RFC2409], ISAKMP [RFC2408]), related networking technology, and networking technology, and general security terms and concepts.
general security terms and concepts.
1.4 Terminology 1.4 Terminology
The following key terms are used throughout this document. The following key terms are used throughout this document.
1-to-N 1-to-N
A group which has one sender and many receivers. A group which has one sender and many receivers.
Group Security Association (GSA) Group Security Association (GSA)
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A bundling of Security Associations (SAs) that together define A bundling of Security Associations (SAs) that together define
how a group communicates securely. The GSA may include an how a group communicates securely. The GSA may include an
registration protocol SA, a rekey protocol SA, and one or more registration protocol SA, a rekey protocol SA, and one or more
data security protocol SAs. data security protocol SAs.
M-to-N M-to-N
A group which has many senders and many receivers, where M and N A group which has many senders and many receivers, where M and N
are not necessarily the same value. are not necessarily the same value.
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Security Association (SA) Security Association (SA)
A set of policy and cryptographic keys that provide security A set of policy and cryptographic keys that provide security
services to network traffic that matches that policy. services to network traffic that matches that policy.
2. Architectural Design: The Multicast Security Reference Framework 2. Architectural Design: The Multicast Security Reference Framework
This section considers the complex issues of multicast security in This section considers the complex issues of multicast security in
the context of a Reference Framework. This reference framework is the context of a Reference Framework. This reference framework is
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Similarly, the reference framework acknowledges that some Similarly, the reference framework acknowledges that some
implementations may in fact merge a number of the "boxes" into a implementations may in fact merge a number of the "boxes" into a
single physical entity. This could be true even across functional single physical entity. This could be true even across functional
areas. For example, an entity in a group could act as both a Group areas. For example, an entity in a group could act as both a Group
Controller and a Sender to a group. Controller and a Sender to a group.
The protocols to be standardized are depicted in the reference The protocols to be standardized are depicted in the reference
framework diagrams by the arrows that connect the various boxes. See framework diagrams by the arrows that connect the various boxes. See
more details in Section 4, below. more details in Section 4, below.
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2.2 Elements of the Centralized Reference Framework 2.2 Elements of the Centralized Reference Framework
The Reference Framework diagram of Figure 1 contains boxes and The Reference Framework diagram of Figure 1 contains boxes and
arrows. The boxes are the functional entities and the arrows are the arrows. The boxes are the functional entities and the arrows are the
interfaces between them. Standard protocols are needed for the interfaces between them. Standard protocols are needed for the
interfaces, which support the multicast services between the interfaces, which support the multicast services between the
functional entities. functional entities.
In some cases, a system implementing the multicast security In some cases, a system implementing the multicast security
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| +------+ ^ | | +------+ ^ |
| | | | | | | | | |
| Multicast |Sender|----------+ | | Multicast |Sender|----------+ |
| Data | | | | Data | | |
| Handling | | | | Handling | | |
| +------+ | | +------+ |
| | | |
+--------------------------------------+ +--------------------------------------+
Figure 1: Centralized Multicast Security Reference Framework Figure 1: Centralized Multicast Security Reference Framework
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2.2.1 Group Controller and Key Server 2.2.1 Group Controller and Key Server
The Group Controller and Key Server (GCKS) represent both the entity The Group Controller and Key Server (GCKS) represent both the entity
and functions relating to the issuance and management of and functions relating to the issuance and management of
cryptographic keys used by a multicast group, which is subject to the cryptographic keys used by a multicast group, which is subject to the
user-authentication and authorization checks conducted on the user-authentication and authorization checks conducted on the
candidate member of the multicast group. candidate member of the multicast group.
The Key Server (KS) and the Group Controller (GC) have somewhat The Key Server (KS) and the Group Controller (GC) have somewhat
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create and manage security policies specific to a multicast group. create and manage security policies specific to a multicast group.
The Policy Server interacts with the GCKS entity in order to install The Policy Server interacts with the GCKS entity in order to install
and manage the security policies related to the membership of a given and manage the security policies related to the membership of a given
multicast group and those related to keying material for a multicast multicast group and those related to keying material for a multicast
group. group.
The interactions between the Policy Server and other entities in the The interactions between the Policy Server and other entities in the
reference framework is dependent to a large extent on the security reference framework is dependent to a large extent on the security
circumstances being addressed by a given policy. circumstances being addressed by a given policy.
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2.3 Elements of the Distributed Reference Framework 2.3 Elements of the Distributed Reference Framework
The need for solutions to be scalable to large groups across wide The need for solutions to be scalable to large groups across wide
geographic regions of the Internet requires the elements of the geographic regions of the Internet requires the elements of the
framework to also function as a distributed system. Figure 2 shows framework to also function as a distributed system. Figure 2 shows
how distributed designs supporting large group scalability fit into how distributed designs supporting large group scalability fit into
the Reference Framework. the Reference Framework.
+-----------------------------------------------------------------+ +-----------------------------------------------------------------+
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In a distributed design the GCKS entity interacts with other GCKS In a distributed design the GCKS entity interacts with other GCKS
entities to achieve scalability in the key management related entities to achieve scalability in the key management related
services. GCKS entities will require a means of authenticating their services. GCKS entities will require a means of authenticating their
peer GCKS entities, a means of authorization, and a means of peer GCKS entities, a means of authorization, and a means of
interacting securely to pass keys and policy. interacting securely to pass keys and policy.
Similarly, Policy Servers must interact with each other securely to Similarly, Policy Servers must interact with each other securely to
allow the communication and enforcement of policies across the allow the communication and enforcement of policies across the
Internet. Internet.
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Two Receiver boxes are displayed corresponding to the situation where Two Receiver boxes are displayed corresponding to the situation where
both the Sender and Receiver employ the same GCKS entity (centralized both the Sender and Receiver employ the same GCKS entity (centralized
architecture) and where the Sender and Receiver employ different GCKS architecture) and where the Sender and Receiver employ different GCKS
entities (distributed architecture). In the distributed design, all entities (distributed architecture). In the distributed design, all
Receivers must obtain identical keys and policy. Each member of a Receivers must obtain identical keys and policy. Each member of a
multicast group may interact with a primary GCKS entity (e.g., the multicast group may interact with a primary GCKS entity (e.g., the
"nearest" GCKS entity, measured in terms of a well-defined and "nearest" GCKS entity, measured in terms of a well-defined and
consistent metric). Similarly, a GCKS entity may interact with one or consistent metric). Similarly, a GCKS entity may interact with one or
more Policy Servers, also arranged in a distributed architecture. more Policy Servers, also arranged in a distributed architecture.
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b. Group authentication. This type of authentication only b. Group authentication. This type of authentication only
guarantees that the data was generated (or last modified) guarantees that the data was generated (or last modified)
by some group member. It does not guarantee data integrity by some group member. It does not guarantee data integrity
unless all group members are trusted. unless all group members are trusted.
While multicast encryption and group authentication are fairly While multicast encryption and group authentication are fairly
standard and similar to encrypting and authenticating point-to-point standard and similar to encrypting and authenticating point-to-point
communication, source authentication for multicast is considerably communication, source authentication for multicast is considerably
more involved. Consequently, off-the-shelf solutions (e.g., taken more involved. Consequently, off-the-shelf solutions (e.g., taken
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from IPSec [RFC2406]) may be sufficient for encryption and group from IPsec [RFC2406]) may be sufficient for encryption and group
authentication. For source authentication, however, special-purpose authentication. For source authentication, however, special-purpose
transformations are necessary. See [CCPRRS] for further transformations are necessary. See [CCPRRS] for further
elaboration on the concerns regarding the data transforms. elaboration on the concerns regarding the data transforms.
Multicast data encrypted and/or authenticated by a sender should be Multicast data encrypted and/or authenticated by a sender should be
handled the same way by both centralized and distributed receivers, handled the same way by both centralized and distributed receivers,
(as shown in Figure 2). (as shown in Figure 2).
The "Multicast Encapsulating Security Payload" [BCCR] provides the The "Multicast Encapsulating Security Payload" [BCCR] provides the
definition for Multicast ESP for data traffic. The "Multicast Source definition for Multicast ESP for data traffic. The "Multicast Source
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circumstance. circumstance.
Core to the area of key management is Security Association (SA) Core to the area of key management is Security Association (SA)
Management, which will be discussed further below. Management, which will be discussed further below.
A "Group Key Management Architecture" document [BCDL] further defines A "Group Key Management Architecture" document [BCDL] further defines
the key management architecture for multicast security. It builds on the key management architecture for multicast security. It builds on
the Group Security Association (GSA) concept, and further defines the the Group Security Association (GSA) concept, and further defines the
roles of the Key Server and Group Controller. roles of the Key Server and Group Controller.
"The Group Domain of Interpretation" [RFC3547], "GSAKMP" [HSMC], and "The Group Domain of Interpretation" [RFC3547], "GSAKMP" [GSAKMP],
"MIKEY" [ACLNM] are three instances of protocols implementing the and "MIKEY" [ACLNM] are three instances of protocols implementing the
group key management function. group key management function.
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3.3 Multicast Security Policies 3.3 Multicast Security Policies
Multicast Security Policies must provide the rules for operation for Multicast Security Policies must provide the rules for operation for
the other elements of the Reference Framework. Security Policies may the other elements of the Reference Framework. Security Policies may
be distributed in an ad-hoc fashion in some instances. However, be distributed in an ad-hoc fashion in some instances. However,
better coordination and higher levels of assurance are achieved if a better coordination and higher levels of assurance are achieved if a
Policy Controller distributes Security Policies policy to the group. Policy Controller distributes Security Policies policy to the group.
Multicast security policies must represent, or contain, more Multicast security policies must represent, or contain, more
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The translation of policy rules from one data model to another is The translation of policy rules from one data model to another is
much more difficult in a multicast group environment. This is much more difficult in a multicast group environment. This is
especially true when group membership spans multiple administrative especially true when group membership spans multiple administrative
domains. Policies specified at a high level with a Policy Management domains. Policies specified at a high level with a Policy Management
tool must be translated into more precise rules that the available tool must be translated into more precise rules that the available
security policy mechanisms can both understand and implement. When security policy mechanisms can both understand and implement. When
dealing with multicast communication and its multiple participants, dealing with multicast communication and its multiple participants,
it is essential that the individual translation performed for each it is essential that the individual translation performed for each
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participant result in the use of a mechanism that is interoperable participant result in the use of a mechanism that is interoperable
with the results of all of the other translations. Typically, the with the results of all of the other translations. Typically, the
translation from high-level policy to specific policy objects must translation from high-level policy to specific policy objects must
result in the same objects in order to achieve communication between result in the same objects in order to achieve communication between
all of the group members. The requirement that policy translation all of the group members. The requirement that policy translation
results in the same objects places constraints on the use and results in the same objects places constraints on the use and
representations in the high-level policies. representations in the high-level policies.
It is also important that policy negotiation and translation be It is also important that policy negotiation and translation be
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protocol). However, group key management may require up to three or protocol). However, group key management may require up to three or
more SAs. These SAs are described in later sections. more SAs. These SAs are described in later sections.
A GSA contains all of the SA attributes identified in the previous A GSA contains all of the SA attributes identified in the previous
section, as well some additional attributes pertaining to the group. section, as well some additional attributes pertaining to the group.
As shown in Figure 3, the GSA builds on the SA in two distinct ways. As shown in Figure 3, the GSA builds on the SA in two distinct ways.
- First, the GSA is a superset of an SA (Figure 3(a)). A GSA has - First, the GSA is a superset of an SA (Figure 3(a)). A GSA has
group policy attributes. For example, the kind of signed group policy attributes. For example, the kind of signed
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credential needed for group membership, whether group members will credential needed for group membership, whether group members will
be given new keys when a member is added (called "backward re-key" be given new keys when a member is added (called "backward re-key"
below), or whether group members will be given new key when a below), or whether group members will be given new key when a
member is removed from the group ("forward re-key"). A GSA also member is removed from the group ("forward re-key"). A GSA also
includes an SA as an attribute of itself. includes an SA as an attribute of itself.
- Second, the GSA is an aggregation of SAs (Figure 3(b)). A GSA is - Second, the GSA is an aggregation of SAs (Figure 3(b)). A GSA is
comprised of multiple SAs, and these SAs may be used for several comprised of multiple SAs, and these SAs may be used for several
independent purposes. independent purposes.
+------------------------------------------------------------+ +---------------+ +-------------------+
| | | GSA | | GSA |
| +---------------+ +-------------------+ | | | | +-----+ +-----+ |
| | GSA | | GSA | | | | | | SA1 | | SA2 | |
| | | | +-----+ +-----+ | | | +----+ | | +-----+ +-----+ |
| | | | | SA1 | | SA2 | | | | | SA | | | +-----+ |
| | +----+ | | +-----+ +-----+ | | | +----+ | | | SA3 | |
| | | SA | | | +-----+ | | | | | +-----+ |
| | +----+ | | | SA3 | | | +---------------+ +-------------------+
| | | | +-----+ | |
| +---------------+ +-------------------+ | (a) superset (b) aggregation
| |
| (a) superset (b) aggregation |
| |
+------------------------------------------------------------+
Figure 3: Relationship of GSA to SA Figure 3: Relationship of GSA to SA
4.3 Structure of a GSA: Reasoning 4.3 Structure of a GSA: Reasoning
Figure 4 shows three categories of SAs that can be aggregated into a Figure 4 shows three categories of SAs that can be aggregated into a
GSA. GSA.
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+------------------------------------------------------------+ +------------------------------------------------------------+
| | | |
| +------------------+ | | +------------------+ |
| | GCKS | | | | GCKS | |
| | | | | | | |
| | REG REG | | | | REG REG | |
| | / REKEY \ | | | | / REKEY \ | |
| +---/-----|----\---+ | | +---/-----|----\---+ |
| / | \ | | / | \ |
| / | \ | | / | \ |
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| | REG | | | REG | | | | REG | | | REG | |
| | REKEY-----+----REKEY | | | | REKEY-----+----REKEY | |
| | SENDER | | RECEIVER | | | | SENDER | | RECEIVER | |
| | DATA----------DATA | | | | DATA----------DATA | |
| +-----------------+ +-----------------+ | | +-----------------+ +-----------------+ |
| | | |
| | | |
+------------------------------------------------------------+ +------------------------------------------------------------+
Figure 4: GSA Structure and 3 categories of SAs Figure 4: GSA Structure and 3 categories of SAs
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The three categories of SAs are: The three categories of SAs are:
- Registration SA (REG): A separate unicast SA between the GCKS and - Registration SA (REG): A separate unicast SA between the GCKS and
each group member, regardless of whether the group member is a each group member, regardless of whether the group member is a
sender or a receiver or acting in both roles. sender or a receiver or acting in both roles.
- Re-key SA (REKEY): A single multicast SA between the GCKS and all - Re-key SA (REKEY): A single multicast SA between the GCKS and all
of the group members. of the group members.
- Data Security SA (DATA): A multicast SA between each multicast - Data Security SA (DATA): A multicast SA between each multicast
skipping to change at line 720 skipping to change at line 721
SA as there are multicast sources allowed by the group's policy. SA as there are multicast sources allowed by the group's policy.
Each of these SAs are defined in more detail in the next section. Each of these SAs are defined in more detail in the next section.
4.4 Definition of GSA 4.4 Definition of GSA
The three categories of SAs correspond to three different kinds of The three categories of SAs correspond to three different kinds of
communications commonly required for group communications. This communications commonly required for group communications. This
section describes the SAs depicted in Figure 4 in detail. section describes the SAs depicted in Figure 4 in detail.
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- Registration SA (REG): - Registration SA (REG):
An SA is required for (bi-directional) unicast communications An SA is required for (bi-directional) unicast communications
between the GCKS and a group member (be it a Sender or Receiver). between the GCKS and a group member (be it a Sender or Receiver).
This SA is established only between the GCKS and a Member. The This SA is established only between the GCKS and a Member. The
GCKS entity is charged with access control to the group keys, GCKS entity is charged with access control to the group keys,
with policy distribution to members (or prospective members), and with policy distribution to members (or prospective members), and
with group key dissemination to Sender and Receiver members. This with group key dissemination to Sender and Receiver members. This
use of a (unicast) SA as a starting point for key management is use of a (unicast) SA as a starting point for key management is
common in a number of group key management environments [RFC3547, common in a number of group key management environments [RFC3547,
HSMC, CCPRRS, RFC2627, BMS,]. GSAKMP, CCPRRS, RFC2627, BMS,].
The Registration SA is initiated by the member to pull GSA The Registration SA is initiated by the member to pull GSA
information from the GCKS. This is how the member requests to information from the GCKS. This is how the member requests to
join the secure group, or has its GSA keys re-initialized after join the secure group, or has its GSA keys re-initialized after
being disconnected from the group (e.g., when its host computer being disconnected from the group (e.g., when its host computer
has been turned off during re-key operations). The GSA has been turned off during re-key operations). The GSA
information pulled down from the GCKS is related to the other two information pulled down from the GCKS is related to the other two
SAs defined as part of the GSA. SAs defined as part of the GSA.
Note that this (unicast) SA is used to protect the other elements Note that this (unicast) SA is used to protect the other elements
of the GSA. As such, the Registration SA is crucial and is of the GSA. As such, the Registration SA is crucial and is
inseparable from the other two SAs in the definition of a GSA. inseparable from the other two SAs in the definition of a GSA.
However, the requirement of a registration SA does not imply the However, the requirement of a registration SA does not imply the
need of a registration protocol to create that Registration SA. need of a registration protocol to create that Registration SA.
The registration SA could instead be setup through some manual The registration SA could instead be setup through some manual
means, such as distributed on a smart card. Thus, what is means, such as distributed on a smart card. Thus, what is
important is that a Registration SA exists, and is used to important is that a Registration SA exists, and is used to
protect the other SAs. protect the other SAs.
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From the perspective of one given GCKS, there are as many unique From the perspective of one given GCKS, there are as many unique
registration SAs as there are members (Senders and/or Receivers) registration SAs as there are members (Senders and/or Receivers)
in the group. This may constitute a scalability concern for some in the group. This may constitute a scalability concern for some
applications. A registration SA may be established on-demand with applications. A registration SA may be established on-demand with
a short lifetime, whereas re-key and data security SAs are a short lifetime, whereas re-key and data security SAs are
established at least for the life of the sessions that they established at least for the life of the sessions that they
support. support.
Conversely the registration SA could be left in place for the Conversely the registration SA could be left in place for the
duration of the group lifetime, if scalability is not an issue. duration of the group lifetime, if scalability is not an issue.
skipping to change at line 777 skipping to change at line 778
In some cases, a GCKS needs the ability to "push" new SAs as part In some cases, a GCKS needs the ability to "push" new SAs as part
of the GSA. These new SAs must be sent to all group members. In of the GSA. These new SAs must be sent to all group members. In
other cases, the GCKS needs the ability to quickly revoke access other cases, the GCKS needs the ability to quickly revoke access
to one or more group members. Both of these needs are satisfied to one or more group members. Both of these needs are satisfied
with the Re-key SA. with the Re-key SA.
This Re-key SA is a unidirectional multicast transmission of key This Re-key SA is a unidirectional multicast transmission of key
management messages from the GCKS to all group members. As such, management messages from the GCKS to all group members. As such,
this SA is known by the GCKS and by all members of the group. this SA is known by the GCKS and by all members of the group.
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This SA is not negotiated, since all the group members must share This SA is not negotiated, since all the group members must share
it. Thus, the GCKS must be the authentic source and act as the it. Thus, the GCKS must be the authentic source and act as the
sole point of contact for the group members to obtain this SA. sole point of contact for the group members to obtain this SA.
A rekey SA is not absolutely required to be part of a GSA. For A rekey SA is not absolutely required to be part of a GSA. For
example, the lifetime of some groups may be short enough such example, the lifetime of some groups may be short enough such
that a rekey is not necessary. Conversely, the policy for the that a rekey is not necessary. Conversely, the policy for the
group could specify multiple rekey SAs of different types. For group could specify multiple rekey SAs of different types. For
example, if the GC and KS are separate entities, the GC may example, if the GC and KS are separate entities, the GC may
deliver rekey messages that adjust the group membership, and the deliver rekey messages that adjust the group membership, and the
skipping to change at line 808 skipping to change at line 806
known by the GCKS and by all members of the group. known by the GCKS and by all members of the group.
Regardless of the number of instances of this third category of Regardless of the number of instances of this third category of
SA, this SA is not negotiated. Rather, all group members obtain SA, this SA is not negotiated. Rather, all group members obtain
it from the GCKS. The GCKS itself does not use this category of it from the GCKS. The GCKS itself does not use this category of
SA. SA.
From the perspective of the Receivers, there is at least one data From the perspective of the Receivers, there is at least one data
security SA for the member sender (one or more) in the group. If security SA for the member sender (one or more) in the group. If
the group has more than one data security SA, the data security the group has more than one data security SA, the data security
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protocol must have a means of differentiating the SAs (e.g., with protocol must have a means of differentiating the SAs (e.g., with
a SPI). a SPI).
There are a number of possibilities with respect to the number of There are a number of possibilities with respect to the number of
data security SAs: data security SAs:
1. Each sender in the group could be assigned a unique data 1. Each sender in the group could be assigned a unique data
security SA, thereby resulting in each receiver having to security SA, thereby resulting in each receiver having to
maintain as many data security SAs as there are senders in the maintain as many data security SAs as there are senders in the
group. In this case, each sender may be verified using source group. In this case, each sender may be verified using source
skipping to change at line 832 skipping to change at line 834
security SA. security SA.
3. A combination of 1. and 2. 3. A combination of 1. and 2.
4.5 Typical Compositions of a GSA 4.5 Typical Compositions of a GSA
Depending on the multicast group policy, many compositions of a GSA Depending on the multicast group policy, many compositions of a GSA
are possible. For illustrative purposes, this section describes a few are possible. For illustrative purposes, this section describes a few
possible compositions. possible compositions.
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- A group of memory-constrained members may require only a REG SA, - A group of memory-constrained members may require only a REG SA,
and a single DATA SA. and a single DATA SA.
- A "pay-per-session" application, where all of the SA information - A "pay-per-session" application, where all of the SA information
needed for the session may be distributed over a REG SA. Re-key needed for the session may be distributed over a REG SA. Re-key
and re-initialization of DATA SAs may not be necessary, so there and re-initialization of DATA SAs may not be necessary, so there
is no REKEY SA. is no REKEY SA.
- A subscription group, where keying material is changed as - A subscription group, where keying material is changed as
membership changes. A REG SA is needed to distribute other SAs; a membership changes. A REG SA is needed to distribute other SAs; a
REKEY SA is needed to re-initialize a DATA SA at the time REKEY SA is needed to re-initialize a DATA SA at the time
membership changes. membership changes.
skipping to change at line 864 skipping to change at line 863
Server and key clients (i.e., the Senders and Receivers of Figure Server and key clients (i.e., the Senders and Receivers of Figure
2), but the services that are needed for multicast key management may 2), but the services that are needed for multicast key management may
be unicast as well as multicast. A security service in the Multicast be unicast as well as multicast. A security service in the Multicast
Security Reference Framework therefore identifies a specific function Security Reference Framework therefore identifies a specific function
along one or more Figure 2 interfaces. along one or more Figure 2 interfaces.
This paper does not attempt to analyze the trust relationships, This paper does not attempt to analyze the trust relationships,
detailed functional requirements, performance requirements, suitable detailed functional requirements, performance requirements, suitable
algorithms, and protocol specifications for IP multicast and algorithms, and protocol specifications for IP multicast and
application-layer multicast security. Instead, that work will occur application-layer multicast security. Instead, that work will occur
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as the security services are further defined and realized in as the security services are further defined and realized in
algorithms and protocols. algorithms and protocols.
5.1 Multicast Data Confidentiality 5.1 Multicast Data Confidentiality
This security service handles the encryption of multicast data at the This security service handles the encryption of multicast data at the
Sender's end and the decryption at the Receiver's end. This security Sender's end and the decryption at the Receiver's end. This security
service may also apply the keying material that is provided by service may also apply the keying material that is provided by
Multicast Key Management in accordance with Multicast Policy Multicast Key Management in accordance with Multicast Policy
Management, but it is independent of both. Management, but it is independent of both.
skipping to change at line 888 skipping to change at line 891
ciphers will be suitable for IP multicast and application-layer ciphers will be suitable for IP multicast and application-layer
multicast traffic. Since this traffic will usually be connectionless multicast traffic. Since this traffic will usually be connectionless
UDP flows, stream ciphers may be unsuitable, though hybrid UDP flows, stream ciphers may be unsuitable, though hybrid
stream/block ciphers may have advantages over some block ciphers. stream/block ciphers may have advantages over some block ciphers.
Regarding application-layer multicast, some consideration is needed Regarding application-layer multicast, some consideration is needed
to consider the effects of sending encrypted data in a multicast to consider the effects of sending encrypted data in a multicast
environment lacking admission-control, where practically any environment lacking admission-control, where practically any
application program can join a multicast event independently of its application program can join a multicast event independently of its
participation in a multicast security protocol. Thus, this security participation in a multicast security protocol. Thus, this security
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service is also concerned with the effects of multicast service is also concerned with the effects of multicast
confidentiality services (intended and otherwise) on application confidentiality services (intended and otherwise) on application
programs. Effects to both senders and receivers is considered. programs. Effects to both senders and receivers is considered.
In Figure 2, the Multicast Data Confidentiality security service is In Figure 2, the Multicast Data Confidentiality security service is
placed in Multicast Data Handling Area along the interface between placed in Multicast Data Handling Area along the interface between
Senders and Receivers. The algorithms and protocols that are Senders and Receivers. The algorithms and protocols that are
realized from work on this security service may be applied to other realized from work on this security service may be applied to other
interfaces and areas of Figure 2 when multicast data confidentiality interfaces and areas of Figure 2 when multicast data confidentiality
is needed. is needed.
skipping to change at line 920 skipping to change at line 919
Management as described below. This is one of the harder areas of Management as described below. This is one of the harder areas of
multicast security due to the connectionless and real-time multicast security due to the connectionless and real-time
requirements of many IP multicast applications. There are classes of requirements of many IP multicast applications. There are classes of
application-layer multicast security, however, where offline source application-layer multicast security, however, where offline source
and data authentication will suffice. As discussed previously, not and data authentication will suffice. As discussed previously, not
all multicast applications require real-time authentication and data- all multicast applications require real-time authentication and data-
packet integrity. A robust solution to multicast source and data packet integrity. A robust solution to multicast source and data
authentication, however, is necessary for a complete solution to authentication, however, is necessary for a complete solution to
multicast security. multicast security.
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In Figure 2, the Multicast Source and Data Authentication security In Figure 2, the Multicast Source and Data Authentication security
service is placed in Multicast Data Handling Area along the interface service is placed in Multicast Data Handling Area along the interface
between Senders and Receivers. The algorithms and protocols that are between Senders and Receivers. The algorithms and protocols that are
produced for this functional area may have applicability to security produced for this functional area may have applicability to security
services in other functional area that use multicast services such as services in other functional area that use multicast services such as
Group Key Management. Group Key Management.
5.3 Multicast Group Authentication 5.3 Multicast Group Authentication
This security service provides a limited amount of authenticity of This security service provides a limited amount of authenticity of
skipping to change at line 943 skipping to change at line 945
are not trusted. are not trusted.
The advantage of group authentication is that it is guaranteed via The advantage of group authentication is that it is guaranteed via
relatively simple and efficient cryptographic transforms. Therefore, relatively simple and efficient cryptographic transforms. Therefore,
when source authentication is not paramount, group authentication when source authentication is not paramount, group authentication
becomes useful. In addition, performing group authentication is becomes useful. In addition, performing group authentication is
useful even when source authentication is later performed: it useful even when source authentication is later performed: it
provides a simple-to-verify weak integrity check that is useful as a provides a simple-to-verify weak integrity check that is useful as a
measure against denial-of-service attacks. measure against denial-of-service attacks.
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The Multicast Group Authentication security service is placed in the The Multicast Group Authentication security service is placed in the
Multicast Data Handling Area along the interface between Senders and Multicast Data Handling Area along the interface between Senders and
Receivers. Receivers.
5.4 Multicast Group Membership Management 5.4 Multicast Group Membership Management
This security service describes the functionality of registration of This security service describes the functionality of registration of
members with the Group Controller, and de-registration of members members with the Group Controller, and de-registration of members
from the Group Controller. These are security functions, which are from the Group Controller. These are security functions, which are
independent from IP multicast group "join" and "leave" operations independent from IP multicast group "join" and "leave" operations
skipping to change at line 976 skipping to change at line 975
De-registration may occur either at the initiative of the member or De-registration may occur either at the initiative of the member or
at the initiative of the group controller. It would result in logging at the initiative of the group controller. It would result in logging
of the de-registration event by the group controller and an of the de-registration event by the group controller and an
invocation of the appropriate mechanism for terminating the invocation of the appropriate mechanism for terminating the
membership of the de-registering member (see Section 5.5). membership of the de-registering member (see Section 5.5).
This security service also describes the functionality of the This security service also describes the functionality of the
communication related to group membership among different GCKS communication related to group membership among different GCKS
servers in a distributed group design. servers in a distributed group design.
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In Figure 2, the Multicast Group Membership security service is In Figure 2, the Multicast Group Membership security service is
placed in the Group Key Management Area and has interfaces to Senders placed in the Group Key Management Area and has interfaces to Senders
and Receivers. and Receivers.
5.5 Multicast Key Management 5.5 Multicast Key Management
This security service describes the functionality of distributing and This security service describes the functionality of distributing and
updating the cryptographic keying material throughout the life of the updating the cryptographic keying material throughout the life of the
group. Components of this security service may include: group. Components of this security service may include:
skipping to change at line 999 skipping to change at line 1001
keys for source authentication, etc). keys for source authentication, etc).
- Updating of current keying material, depending on circumstances - Updating of current keying material, depending on circumstances
and policies. and policies.
- Termination of groups in a secure manner, including the - Termination of groups in a secure manner, including the
multicast group itself and the associated keying material. multicast group itself and the associated keying material.
Among the responsibilities of this security service is the secure Among the responsibilities of this security service is the secure
management of keys between Key Servers and Clients, the addressing management of keys between Key Servers and Clients, the addressing
issues for the multicast distribution of keying material, and the issues for the multicast distribution of keying material, and the
scalability or other performance requirements for multicast key scalability or other performance requirements for multicast key
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management [RFC2627, BMS]. Key Servers and Clients may take advantage management [RFC2627, BMS]. Key Servers and Clients may take advantage
of a common Public Key Infrastructure (PKI) for increased scalability of a common Public Key Infrastructure (PKI) for increased scalability
of authentication and authorization. of authentication and authorization.
To allow for an interoperable and secure IP multicast security To allow for an interoperable and secure IP multicast security
protocol, this security service may need to specify host abstractions protocol, this security service may need to specify host abstractions
such as a group security association database (GSAD) and a group such as a group security association database (GSAD) and a group
security policy database (GSPD) for IP multicast security. The security policy database (GSPD) for IP multicast security. The
degree of overlap between IP multicast and application-layer degree of overlap between IP multicast and application-layer
multicast key management needs to be considered. Thus, this security multicast key management needs to be considered. Thus, this security
skipping to change at line 1032 skipping to change at line 1030
security). security).
This security service also describes the functionality of the This security service also describes the functionality of the
communication related to key management among different GCKS servers communication related to key management among different GCKS servers
in a distributed group design. in a distributed group design.
Multicast Key Management appears in both the centralized and Multicast Key Management appears in both the centralized and
distributed designs as shown in Figure 2 and is placed in the Group distributed designs as shown in Figure 2 and is placed in the Group
Key Management Area. Key Management Area.
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5.6 Multicast Policy Management 5.6 Multicast Policy Management
This security service handles all matters related to multicast group This security service handles all matters related to multicast group
policy including membership policy and multicast key management policy including membership policy and multicast key management
policy. Indeed, one of the first tasks in further defining this policy. Indeed, one of the first tasks in further defining this
security service is identifying the different areas of multicast security service is identifying the different areas of multicast
policy. Multicast Policy Management includes the design of the policy policy. Multicast Policy Management includes the design of the policy
server for multicast security, the particular policy definitions that server for multicast security, the particular policy definitions that
will be used for IP multicast and application-layer multicast will be used for IP multicast and application-layer multicast
security, and the communication protocols between the Policy Server security, and the communication protocols between the Policy Server
skipping to change at line 1056 skipping to change at line 1057
multicast security policy. At minimum, however, this security service multicast security policy. At minimum, however, this security service
will be realized in a set of policy definitions, such as multicast will be realized in a set of policy definitions, such as multicast
security conditions and actions. security conditions and actions.
The Multicast Policy Management security service describes the The Multicast Policy Management security service describes the
functionality of the communication between an instance of a GCKS to functionality of the communication between an instance of a GCKS to
an instance the Policy Server. The information transmitted may an instance the Policy Server. The information transmitted may
include policies concerning groups, memberships, keying material include policies concerning groups, memberships, keying material
definition and their permissible uses, and other information. This definition and their permissible uses, and other information. This
security service also describes communication between and among security service also describes communication between and among
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Policy Servers. Group members are not expected to directly Policy Servers. Group members are not expected to directly
participate in this security service. However, this option is not participate in this security service. However, this option is not
ruled out. ruled out.
6. Security Considerations 6. Security Considerations
This document describes an architectural framework for protecting This document describes an architectural framework for protecting
multicast and group traffic with cryptographic protocols. Three multicast and group traffic with cryptographic protocols. Three
functional areas are identified within the framework. Each functional functional areas are identified within the framework. Each functional
area has unique security considerations, and these are discussed area has unique security considerations, and these are discussed
below. below.
This architectural framework is end-to-end, and does not rely upon This architectural framework is end-to-end, and does not rely upon
the network that connects group controllers and group members. As the network that connects group controllers and group members. It
such, denial of service, message deletion, and other active attacks also does not attempt to resolve security issues in the unicast or
on the unicast or multicast routing infrastructures are not addressed multicast routing infrastructures, or in multicast admission control
by this framework. protocols. As such, denial of service, message deletion, and other
active attacks against the unicast or multicast routing
infrastructures are not addressed by this framework. Section 1.1
describes the relationship of the network infrastructure to the
multicast group security architecture.
6.1 Multicast Data Handling 6.1 Multicast Data Handling
Cryptographic protocols protecting multicast data are responsible for Cryptographic protocols protecting multicast data are responsible for
providing confidentiality and group authentication. They should also providing confidentiality and group authentication. They should also
be able to provide source authentication to uniquely identify senders be able to provide source authentication to uniquely identify senders
to the group. Replay protection of multicast data is also desirable, to the group. Replay protection of multicast data is also desirable,
but may not always be possible. This is due to the complexity of but may not always be possible. This is due to the complexity of
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maintaining replay protection state for multiple senders. Section 3.1 maintaining replay protection state for multiple senders. Section 3.1
elaborates on the security requirements for this area. elaborates on the security requirements for this area.
6.2 Group Key Management 6.2 Group Key Management
Group key management protocols provide cryptographic keys and policy Group key management protocols provide cryptographic keys and policy
to group members. They are responsible for authenticating and to group members. They are responsible for authenticating and
authorizing group members before revealing those keys, and for authorizing group members before revealing those keys, and for
providing confidentiality and authentication of those keys during providing confidentiality and authentication of those keys during
transit. They are also responsible for providing a means for rekeying transit. They are also responsible for providing a means for rekeying
skipping to change at line 1109 skipping to change at line 1114
of this area in more detail. of this area in more detail.
6.3 Multicast Security Policies 6.3 Multicast Security Policies
Cryptographic protocols providing multicast security policies are Cryptographic protocols providing multicast security policies are
responsible for distributing that policy such that the integrity of responsible for distributing that policy such that the integrity of
the policy is maintained. If the policy itself is confidential, they the policy is maintained. If the policy itself is confidential, they
also are responsible for authenticating group controllers and group also are responsible for authenticating group controllers and group
members, and providing confidentiality of the policy during transit. members, and providing confidentiality of the policy during transit.
7. Acknowledgments 7. Intellectual Property Rights Statement
Much of the text in this document was derived from two research The IETF takes no position regarding the validity or scope of any
papers. The framework for this document came from a paper co-authored intellectual property or other rights that might be claimed to
pertain to the implementation or use of the technology described in
this document or the extent to which any license under such rights
might or might not be available; neither does it represent that it
has made any effort to identify any such rights. Information on the
IETF's procedures with respect to rights in standards-track and
standards-related documentation can be found in BCP-11. Copies of
claims of rights made available for publication and any assurances
of licenses to be made available, or the result of an attempt made
to obtain a general license or permission for the use of such
proprietary rights by implementors or users of this specification
can be obtained from the IETF Secretariat.
Hardjono, Weis Expires May, 2004 21 The IETF invites any interested party to bring to its attention any
MSEC Architecture November, 2003 copyrights, patents or patent applications, or other proprietary
rights which may cover technology that may be required to practice
this standard. Please address the information to the IETF Executive
Director.
8. Acknowledgments
Much of the text in this document was derived from two research
papers. The framework for this document came from a paper co-authored
by Thomas Hardjono, Ran Canetti, Mark Baugher, and Pete Dinsmore. by Thomas Hardjono, Ran Canetti, Mark Baugher, and Pete Dinsmore.
Description of the GSA came from a document co-authored by Hugh Description of the GSA came from a document co-authored by Hugh
Harney, Mark Baugher, and Thomas Hardjono. George Gross suggested a Harney, Mark Baugher, and Thomas Hardjono. George Gross suggested a
Hardjono, Weis Expires July, 2004 21
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number of improvements that were included in later versions of this number of improvements that were included in later versions of this
document. document.
8. References 9. References
8.1 Normative References 9.1 Normative References
[RFC2401] S. Kent, R. Atkinson, Security Architecture for the [RFC2401] S. Kent, R. Atkinson, Security Architecture for the
Internet Protocol, November 1998. Internet Protocol, November 1998.
[RFC2408] D. Maughan, M. Shertler, M. Schneider, J. Turner, Internet [RFC2408] D. Maughan, M. Shertler, M. Schneider, J. Turner, Internet
Security Association and Key Management Protocol, November 1998. Security Association and Key Management Protocol, November 1998.
[RFC2409] D. Harkins, D. Carrel, The Internet Key Exchange (IKE), 9.2 Informative References
November, 1998.
[RFC3552] E. Rescorla, et. al., Guidelines for Writing RFC Text on
Security Considerations, RFC 3552, July 2003.
8.2 Informative References
[ACLNM] J. Arkko, et. al., MIKEY: Multimedia Internet KEYing, draft- [ACLNM] J. Arkko, et. al., MIKEY: Multimedia Internet KEYing, draft-
ietf-msec-mikey-06.txt, February, 2003. Work in Progress. ietf-msec-mikey-08.txt, December, 2003. Work in Progress.
[BCCR] M. Baugher, R. Canetti, P. Cheng, P. Rohatgi, MESP: A [BCCR] M. Baugher, R. Canetti, P. Cheng, P. Rohatgi, MESP: A
Multicast Framework for the Ipsec ESP, draft-ietf-msec-mesp-01.txt. Multicast Framework for the IPsec ESP, draft-ietf-msec-mesp-01.txt.
October 2002. Work in Progress. October 2002. Work in Progress.
[BCDL] M. Baugher, R. Canetti, L. Dondeti, F. Lindholm, Group Key [BCDL] M. Baugher, R. Canetti, L. Dondeti, F. Lindholm, Group Key
Management Architecture, draft-ietf-msec-gkmarch-04.txt. March 2003. Management Architecture, draft-ietf-msec-gkmarch-06.txt. September
Work in Progress. 08, 2003. Work in Progress.
[BMS] D. Balenson, D. McGrew, A. Sherman, Key Management for Large [BMS] D. Balenson, D. McGrew, A. Sherman, Key Management for Large
Dynamic Groups: One-Way Function Trees and Amortized Initialization, Dynamic Groups: One-Way Function Trees and Amortized Initialization,
http://www.securemulticast.org/draft-balenson-groupkeymgmt-oft- http://www.securemulticast.org/draft-balenson-groupkeymgmt-oft-
00.txt, February 1999, Work in Progress. 00.txt, February 1999, Work in Progress.
[CCPRRS] Canetti, R., Cheng P. C., Pendarakis D., Rao, J., Rohatgi [CCPRRS] Canetti, R., Cheng P. C., Pendarakis D., Rao, J., Rohatgi
P., Saha D., "An IPSec-based Host Architecture for Secure Internet P., Saha D., "An IPSec-based Host Architecture for Secure Internet
Multicast", Multicast",
http://www.isoc.org/isoc/conferences/ndss/2000/proceedings/028.pdf, http://www.isoc.org/isoc/conferences/ndss/2000/proceedings/028.pdf,
NDSS 2000. NDSS 2000.
[Din] Dinsmore, P., Balenson, D., Heyman, M., Kruus, P., Scace, C., [Din] Dinsmore, P., Balenson, D., Heyman, M., Kruus, P., Scace, C.,
and Sherman, A., "Policy-Based Security Management for Large Dynamic and Sherman, A., "Policy-Based Security Management for Large Dynamic
Groups: An Overview of the DCCM Project," DARPA Information Groups: An Overview of the DCCM Project," DARPA Information
Survivability Conference and Exposition, Survivability Conference and Exposition,
http://download.nai.com/products/media/nai/doc/discex-110199.doc. http://download.nai.com/products/media/nai/doc/discex-110199.doc.
Hardjono, Weis Expires May, 2004 22 [GSAKMP] H. Harney, et. al., GSAKMP. draft-ietf-msec-gsakmp-sec-
MSEC Architecture November, 2003 04.txt. October 2003. Work in Progress.
[Har1] Harney, H., and Muckenhirn, C., "Group Key Management [Har1] Harney, H., and Muckenhirn, C., "Group Key Management
Protocol (GKMP) Specification," RFC 2093, July 1997. Protocol (GKMP) Specification," RFC 2093, July 1997.
[Har2] Harney, H., and Muckenhirn, C., "Group Key Management [Har2] Harney, H., and Muckenhirn, C., "Group Key Management
Protocol (GKMP) Architecture," RFC 2094, July 1997. Protocol (GKMP) Architecture," RFC 2094, July 1997.
[HSMC] H. Harney, A. Schuett, U. Meth, A. Colegrove, GSAKMP. draft- Hardjono, Weis Expires July, 2004 22
ietf-msec-gsakmp-sec-01.txt. February 2003. Work in Progress. The Multicast Group Security Architecture January, 2004
[McD] McDaniel, P., Honeyman, P., and Prakash, A., "Antigone: [McD] McDaniel, P., Honeyman, P., and Prakash, A., "Antigone:
A Flexible Framework for Secure Group Communication," Proceedings of A Flexible Framework for Secure Group Communication," Proceedings of
the Eight USENIX Security Symposium, pp 99-113, August, 1999. the Eight USENIX Security Symposium, pp 99-113, August, 1999.
[PCW] A. Perrig, R. Canetti, B. Whillock, TESLA: Multicast Source [PCW] A. Perrig, R. Canetti, B. Whillock, TESLA: Multicast Source
Authentication Transform Specification. draft-ietf-msec-tesla-spec- Authentication Transform Specification. draft-ietf-msec-tesla-spec-
00.txt. IETF, October 2002. Work in Progress. 00.txt. IETF, October 2002. Work in Progress.
[RFC2362] Estrin, D., et. al., Protocol Independent Multicast-Sparse [RFC2362] Estrin, D., et. al., Protocol Independent Multicast-Sparse
Mode (PIM-SM): Protocol Specification, RFC 2362, June, 1998. Mode (PIM-SM): Protocol Specification, RFC 2362, June, 1998.
[RFC2406] S. Kent, R. Atkinson, IP Encapsulating Security Payload [RFC2406] S. Kent, R. Atkinson, IP Encapsulating Security Payload
(ESP), RFC 2406, November 1998. (ESP), RFC 2406, November 1998.
[RFC2406bis] S. Kent, IP Encapsulating Security Payload (ESP), [RFC2406bis] S. Kent, IP Encapsulating Security Payload (ESP),
draft-ietf-ipsec-esp-v3-04.txt, March 2003. Work In Progress. draft-ietf-ipsec-esp-v3-04.txt, March 2003. Work In Progress.
[RFC2409] D. Harkins, D. Carrel, The Internet Key Exchange (IKE),
November, 1998.
[RFC2627] D. M. Wallner, E. Harder, R. C. Agee, Key Management for [RFC2627] D. M. Wallner, E. Harder, R. C. Agee, Key Management for
Multicast: Issues and Architectures, RFC 2627, September 1998. Multicast: Issues and Architectures, RFC 2627, September 1998.
[RFC2663] P. Srisuresh, M. Holdrege, IP Network Address Translator [RFC2663] P. Srisuresh, M. Holdrege, IP Network Address Translator
(NAT) Terminology and Considerations, RFC 2663, August 1999. (NAT) Terminology and Considerations, RFC 2663, August 1999.
[RFC2748] D. Durham, et. al., The COPS (Common Open Policy Service) [RFC2748] D. Durham, et. al., The COPS (Common Open Policy Service)
Protocol, RFC 2748, January, 2000. Protocol, RFC 2748, January, 2000.
[RFC3019] B. Haberman, Worzella, R., IP Version 6 Management [RFC3019] B. Haberman, Worzella, R., IP Version 6 Management
skipping to change at line 1223 skipping to change at line 1247
[RFC3453] M. Luby, et. al., The Use of Forward Error Correction [RFC3453] M. Luby, et. al., The Use of Forward Error Correction
(FEC) in Reliable Multicast, RFC 3453, December 2002. (FEC) in Reliable Multicast, RFC 3453, December 2002.
[RFC3547] M. Baugher, B. Weis, T. Hardjono, H. Harney, , The Group [RFC3547] M. Baugher, B. Weis, T. Hardjono, H. Harney, , The Group
Domain of Interpretation, RFC 3547, December 2002. Domain of Interpretation, RFC 3547, December 2002.
[STW] M. Steiner, Tsudik, G., Waidner, M., CLIQUES: A New Approach to [STW] M. Steiner, Tsudik, G., Waidner, M., CLIQUES: A New Approach to
Group key Agreement, IEEE ICDCS'98 , May 1998. Group key Agreement, IEEE ICDCS'98 , May 1998.
Hardjono, Weis Expires May, 2004 23 Hardjono, Weis Expires July, 2004 23
MSEC Architecture November, 2003 The Multicast Group Security Architecture January, 2004
Authors Addresses Authors Addresses
Thomas Hardjono Thomas Hardjono
VeriSign VeriSign
487 E. Middlefield Rd. 487 E. Middlefield Rd.
Mountain View, CA 94043, USA Mountain View, CA 94043, USA
Phone:(650) 426-3204 Phone:(650) 426-3204
EMail: thardjono@verisign.com EMail: thardjono@verisign.com
Brian Weis Brian Weis
Cisco Systems Cisco Systems
170 W. Tasman Drive, 170 W. Tasman Drive,
San Jose, CA 95134-1706, USA San Jose, CA 95134-1706, USA
Phone: (408) 526-4796 Phone: (408) 526-4796
EMail: bew@cisco.com EMail: bew@cisco.com
Hardjono, Weis Expires May, 2004 24 Full Copyright Statement
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Acknowledgement
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Hardjono, Weis Expires July, 2004 24
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