draft-ietf-mboned-maccnt-req-05.txt		draft-ietf-mboned-maccnt-req-06.txt
	Tsunemasa Hayashi, NTT		Tsunemasa Hayashi, NTT
	Internet Draft Haixiang He, Nortel		Internet Draft Haixiang He, Nortel
	Document:draft-ietf-mboned-maccnt-req-05.txt Hiroaki Satou, NTT		Document:draft-ietf-mboned-maccnt-req-06.txt Hiroaki Satou, NTT
	Intended Status: Informational Hiroshi Ohta, NTT		Intended Status: Informational Hiroshi Ohta, NTT
	Expires: March 22, 2008 Susheela Vaidya, Cisco Systems		Expires: December 22, 2008 Susheela Vaidya, Cisco Systems
	September 19, 2007		June 20, 2008
	Requirements for Multicast AAA coordinated between Content		Requirements for Multicast AAA coordinated between Content
	Provider(s) and Network Service Provider(s) <draft-ietf-mboned-		Provider(s) and Network Service Provider(s) <draft-ietf-mboned-
	maccnt-req-05.txt>		maccnt-req-06.txt>
	Status of this Memo		Status of this Memo
	By submitting this Internet-Draft, each author represents that		By submitting this Internet-Draft, each author represents that
	any applicable patent or other IPR claims of which he or she is		any applicable patent or other IPR claims of which he or she is
	aware have been or will be disclosed, and any of which he or she		aware have been or will be disclosed, and any of which he or she
	becomes aware will be disclosed, in accordance with Section 6 of		becomes aware will be disclosed, in accordance with Section 6 of
	BCP 79.		BCP 79.
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	This Internet-Draft will expire on March 22, 2008.
	Copyright Notice
	Copyright (C) The IETF Copyright (C) The IETF Trust (2007). This
	document is subject to the rights, licenses and restrictions
	contained in BCP 78, and except as set forth therein, the authors
	retain all their rights. Trust (2007). This document is subject
	to the rights, licenses and restrictions contained in BCP 78, and
	except as set forth therein, the authors retain all their rights.
	Abstract		Abstract
	This memo presents requirements in the area of accounting and		This memo presents requirements in the area of accounting and
	access control for IP multicasting. The scope of the requirements		access control for IP multicasting. The scope of the requirements
	is limited to cases that Authentication, Accounting and		is limited to cases that Authentication, Accounting and
	Authorization (AAA) functions are coordinated between Content		Authorization (AAA) functions are coordinated between Content
	Provider(s) and Network Service Provider(s). General requirements		Provider(s) and Network Service Provider(s). General requirements
	for accounting and admission control capabilities including		for accounting and admission control capabilities including
	quality-of-service (QoS) related issues are listed. This memo		quality-of-service (QoS) related issues are listed. This memo
	assumes that these capabilities can be realized by functions		assumes that these capabilities can be realized by functions
	implemented at edges of a network based on IGMP or MLD. Finally,		implemented at edges of a network based on IGMP or MLD. Finally,
	cases for Content Delivery Services (CDS) are described as		cases for Content Delivery Services (CDS) are described as
	application examples which could benefit from multicasting		application examples which could benefit from multicasting
	accounting and access control capabilities as described in the		accounting and access control capabilities as described in this
	memo.		memo.
	This memo defines requirements related to AAA issues for multi-		This memo defines requirements related to AAA issues for multi-
	entity provider models in which the network service provider and		entity provider models in which the network service provider and
	content provider cooperate to provide CDS and various related AAA		content provider cooperate to provide CDS and various related AAA
	functions for purposes such as protecting and accounting for the		functions for purposes such as protecting and accounting for the
	access to content and network resources. The requirements are		access to content and network resources. The requirements are
	generally not relevant to cases in which there is not a reason to		generally not relevant to cases in which there is not a reason to
	share AAA functions between separate entities.		share AAA functions between separate entities.
	skipping to change at page 3, line 42		skipping to change at page 3, line 42
	10. Conclusion..................................................21		10. Conclusion..................................................21
	Normative References............................................22		Normative References............................................22
	Authors' Addresses..............................................23		Authors' Addresses..............................................23
	Full Copyright Statement........................................24		Full Copyright Statement........................................24
	Intellectual Property...........................................24		Intellectual Property...........................................24
	Expiration......................................................25		Expiration......................................................25
	Acknowledgement.................................................25		Acknowledgement.................................................25
	1. Introduction		1. Introduction
	This memo will present general functional requirements related to		This memo presents general functional requirements related to
	accounting, access control and admission control issues in IP		accounting, access control and admission control issues in IP
	multicasting networks. A multicast network which fulfills all of		multicasting networks. A multicast network which fulfills all of
	these requirements will be called a "fully AAA and QoS enabled" IP		these requirements is called a "fully AAA and QoS enabled" IP
	multicasting network. Fulfillment of all or some of the		multicasting network here. Fulfillment of all or some of the
	requirements will make possible more robust management of IP		requirements will make possible more robust management of IP
	multicasting networks.		multicasting networks.
	IP multicasting is becoming widely used as a method to save		IP multicasting is becoming widely used as a method to save
	network resources such as bandwidth or CPU processing power of the		network resources such as bandwidth or CPU processing power of the
	sender's server for cases where a large volume of information		sender's server for cases where a large volume of information
	needs to be distributed to a very large number of receivers at a		needs to be distributed to a very large number of receivers at a
	given data speed. This trend can be observed both in enterprise		given data speed. This trend can be observed both in enterprise
	use and in broadband services provided by network operator/service		use and in broadband services provided by network operator/service
	providers.		providers.
	Distance learning within a university and in-house (in-company)		Distance learning within a university and in-house (in-company)
	sharing of multimedia information are examples of enterprise use.		sharing of multimedia information are examples of enterprise use.
	In these examples, sources generate high-bit rate (e.g., 6Mbit/s)		In these examples, sources generate high-bit rate (e.g., 6Mbit/s)
	streaming information. When the number of receivers becomes		streaming information. When the number of receivers becomes large,
	large, such systems do not scale well without multicasting.		such systems do not scale well without multicasting.
	On the other hand, a Content Delivery Service (CDS) is an example		On the other hand, a content delivery service (CDS) is an example
	of a broadband service provided by network operators/service		of a broadband service provided by network operators/service
	providers. Distribution of movies and other video programs to		providers. Distribution of movies and other video programs to
	each user are typical services. Each channel requires large		each user is a typical service. Each channel requires large
	bandwidth (e.g., 6Mbit/s) and operator/service providers need to		bandwidth (e.g., 6Mbit/s) and operator/service providers need to
	provide many channels to make their service attractive. In		provide many channels to make their service attractive. In
	addition, the number of receivers is large (e.g., more than a few		addition, the number of receivers is large (e.g., more than a few
	thousands). The system to provide this service does not scale		thousands). A system to provide this service does not scale well
	well without multicasting.		without multicasting.
	As such, multicasting can be useful to make the network more		As such, multicasting can be useful to make a network more
	scalable when a large volume of information needs to be		scalable when a large volume of information needs to be
	distributed to a large number of receivers. However, multicasting		distributed to a large number of receivers. However, multicasting
	according to current standards (e.g., IGMPv3[1] and MLDv2[2]) has		according to current standards (e.g., IGMPv3[1] and MLDv2[2]) has
	drawbacks compared to unicasting when one applies it to commercial		drawbacks compared to unicasting when one applies it to commercial
	services. Accounting of each user's actions is not possible with		services. Accounting of each user's actions is not possible with
	multicasting as it is with unicasting. Accounting consists of		multicasting as it is with unicasting. Accounting consists of
	grasping each user's behavior, when she/he starts/stops to receive		grasping each user's behavior, when she/he starts/stops to receive
	a channel, which channel she/he receives, etc.		a channel, which channel she/he receives, etc.
	There are limitations to the application of multicasting in usage		There are limitations to the application of multicasting in usage
	skipping to change at page 9, line 19		skipping to change at page 9, line 19
	(1) User identification		(1) User identification
	The network should be able to identify each user when they attempt		The network should be able to identify each user when they attempt
	to access the service so that necessary access controlling actions		to access the service so that necessary access controlling actions
	can be applied. Also, it is necessary to identify the user's		can be applied. Also, it is necessary to identify the user's
	receiver (e.g. IP address) of each request (e.g., join/leave) for		receiver (e.g. IP address) of each request (e.g., join/leave) for
	per host tracking purposes.		per host tracking purposes.
	With current protocols (IGMP/MLD), the sender cannot distinguish		With current protocols (IGMP/MLD), the sender cannot distinguish
	which receivers (end hosts) are actually receiving the		which receivers (end hosts) are actually receiving the information.
	information. The sender must rely on the information from the		The sender must rely on the information from the multicasting
	multicasting routers. This can be complicated if the sender and		routers. This can be complicated if the sender and routers are
	routers are maintained by different entities.		maintained by different entities.
	(2) Issue of Network Resource Protection		(2) Issue of Network Resource Protection
	In order to guarantee certain QoS it is important for network		In order to guarantee certain QoS it is important for network
	providers to be able to protect their network resources from being		providers to be able to protect their network resources from being
	wasted, (either maliciously or accidentally).		wasted, (either maliciously or accidentally).
	For comparisons sake, for unicast this issue can be resolved e.g.		For comparisons sake, for unicast this issue can be resolved e.g.
	by using RSVP in some cases.		by using RSVP in some cases.
	skipping to change at page 15, line 8		skipping to change at page 15, line 8
	One way to provide high quality CDS is to use closed networks		One way to provide high quality CDS is to use closed networks
	("walled-garden" model).		("walled-garden" model).
	This subsection shows an example where CP and NSP are different		This subsection shows an example where CP and NSP are different
	entities (companies).		entities (companies).
	5.1.1 Network Model for Multicast Content Delivery Service		5.1.1 Network Model for Multicast Content Delivery Service
	As shown in Fig.2, networks for CDS contain three different types		As shown in Fig.2, networks for CDS contain three different types
	of entities: Content Provider (CP), Network Service Provider		of entities: Content Provider (CP), Network Service Provider (NSP),
	(NSP), and user clients. An NSP owns the network resources		and user clients. An NSP owns the network resources
	(infrastructure). It accommodates content providers on one side		(infrastructure). It accommodates content providers on one side
	and accommodates user clients on the other side. NSP provides the		and accommodates user clients on the other side. NSP provides the
	network for CDS to two other entities (i.e., CPs and user		network for CDS to two other entities (i.e., CPs and user clients).
	clients). A CP provides content to each user through the network		A CP provides content to each user through the network of NSPs.
	of NSPs. NSPs are responsible for delivering the content to user		NSPs are responsible for delivering the content to user clients,
	clients, and for controlling the network resources.		and for controlling the network resources.
	+-------------+ +-------------+ +-------------+		+-------------+ +-------------+ +-------------+
	| CP | | CP | | CP |		| CP | | CP | | CP |
	| #1 | | #2 | | #3 |		| #1 | | #2 | | #3 |
	| +---------+ | | +---------+ | | +---------+ |		| +---------+ | | +---------+ | | +---------+ |
	| | content | | | | content | | | | content | |		| | content | | | | content | | | | content | |
	| | server | | | | server | | | | server | |		| | server | | | | server | | | | server | |
	| +-------+-+ | | +----+----+ | | +-+-------+ |		| +-------+-+ | | +----+----+ | | +-+-------+ |
	+----------\--+ +------|------+ +--/----------+		+----------\--+ +------|------+ +--/----------+
	\ | /		\ | /
	skipping to change at page 16, line 38		skipping to change at page 16, line 38
	/ | \		/ | \
	/ | \ <- user/network interface		/ | \ <- user/network interface
	/ | \		/ | \
	+---------++ +-----+----+ ++---------+		+---------++ +-----+----+ ++---------+
	|client #a | |client #b | |client #c |		|client #a | |client #b | |client #c |
	+----------+ +----------+ +----------+		+----------+ +----------+ +----------+
	User A User B User C		User A User B User C
	Fig.2 Example of CDS network configuration		Fig.2 Example of CDS network configuration
	The NSP provides the information server for all multicast		The NSP provides the information server for all multicast channels,
	channels, and a CP gives detailed channel information (e.g., Time		and a CP gives detailed channel information (e.g., Time table of
	table of each channel) to the information server. An end-user		each channel) to the information server. An end-user client gets
	client gets the information from the information server. In this		the information from the information server. In this model,
	model, multicasting is used in the NSP's CDS network, and there		multicasting is used in the NSP's CDS network, and there are two
	are two different contracts. One is the contract between the NSP		different contracts. One is the contract between the NSP and the
	and the user which permits the user to access the basic network		user which permits the user to access the basic network resources
	resources of the NSP. Another contract is between the CP and user		of the NSP. Another contract is between the CP and user to permit
	to permit the user to subscribe to multicast content. Because the		the user to subscribe to multicast content. Because the CP and NSP
	CP and NSP are different entities, and the NSP generally does not		are different entities, and the NSP generally does not allow a CP
	allow a CP to control (operate) the network resources of the NSP,		to control (operate) the network resources of the NSP, user
	user authorization needs to be done by the CP and NSP		authorization needs to be done by the CP and NSP independently.
	independently. Since there is no direct connection to the		Since there is no direct connection to the user/network interface,
	user/network interface, the CP cannot control the user/network		the CP cannot control the user/network interface. A user may want
	interface. A user may want to move to another place, or may want		to move to another place, or may want to change her/his device
	to change her/his device (client) any time without interrupting		(client) any time without interrupting her/his reception of
	her/his reception of services. As such, IP Multicast network		services. As such, IP Multicast network should support
	should support portability capabilities.		portability capabilities.
	5.1.2 Content Delivery Service Requirements		5.1.2 Content Delivery Service Requirements
	Below are listed specific requirements to support common business		Below are listed specific requirements to support common business
	cases/ contractual arrangements for the IP Multicast-based Content		cases/ contractual arrangements for the IP Multicast-based Content
	Delivery Service.		Delivery Service.
	5.1.2.1 Accounting Requirements		5.1.2.1 Accounting Requirements
	An NSP may have different contractual agreements with various CPs		An NSP may have different contractual agreements with various CPs
	skipping to change at page 18, line 10		skipping to change at page 18, line 10
	their user edges. The NSPs can transfer the accounting information		their user edges. The NSPs can transfer the accounting information
	to related CPs for them to generate user billing information.		to related CPs for them to generate user billing information.
	Existing standard AAA technology may be used to transfer the		Existing standard AAA technology may be used to transfer the
	accounting information.		accounting information.
	To match the accounting information with a particular user, the		To match the accounting information with a particular user, the
	user has to be authenticated. Usually the account information of a		user has to be authenticated. Usually the account information of a
	user for content access is maintained by the CP. A user may have		user for content access is maintained by the CP. A user may have
	different user accounts for different CPs.(e.g. user_a@cp#1 and		different user accounts for different CPs.(e.g. user_a@cp#1 and
	user_b@cp#2) The account is usually in the format of (username,		user_b@cp#2) The account is usually in the format of (username,
	password) so an user can access the content services from		password) so an user can access the content services from anywhere.
	anywhere. For example, an user can access the CP from different		For example, an user can access the CP from different NSPs.(e.g. a
	NSPs.(e.g. a fixed line NSP and a mobile NSP). It should be noted		fixed line NSP and a mobile NSP). It should be noted that the user
	that the user account used for content access can be different		account used for content access can be different from the one used
	from the one used for network access maintained by NSPs.		for network access maintained by NSPs.
	The NSP-CP model represents a multi-domain AAA environment. There		The NSP-CP model represents a multi-domain AAA environment. There
	are plural cases of the model depending on the trust relationship		are plural cases of the model depending on the trust relationship
	between the NSP and CP, and additional service requirements such		between the NSP and CP, and additional service requirements such
	as a certain QoS level guarantee or service/terminal portability.		as a certain QoS level guarantee or service/terminal portability.
	A mechanism is necessary to allow a CP and NSP to grasp each		A mechanism is necessary to allow a CP and NSP to grasp each
	user's behavior independently.		user's behavior independently.
	Another requirement related to accounting is the ability to notify		Another requirement related to accounting is the ability to notify
	skipping to change at page 19, line 25		skipping to change at page 19, line 25
	In order to protect network resources against misuse/malicious		In order to protect network resources against misuse/malicious
	access and maintain a QoS level, appropriate admission control		access and maintain a QoS level, appropriate admission control
	function for traffic policing purposes is necessary so that the NSP		function for traffic policing purposes is necessary so that the NSP
	can accept or reject the request without degrading the QoS beyond		can accept or reject the request without degrading the QoS beyond
	the specified level.		the specified level.
	5.1.2.3 Authentication Requirements		5.1.2.3 Authentication Requirements
	There are two different aims of authentication. One is		There are two different aims of authentication. One is
	authentication for network access, and another one is for content		authentication for network access, and another one is for content
	access. For the first case of authentication, NSP has a AAA		access. For the first case of authentication, NSP has a AAA server,
	server, and for the second case, each CP has a AAA server. In some		and for the second case, each CP has a AAA server. In some cases,
	cases, CPs delegate (outsource) the operation of user		CPs delegate (outsource) the operation of user authentication to
	authentication to NSPs.		NSPs.
	As such, in addition to network access, multicast access by a user		As such, in addition to network access, multicast access by a user
	also needs to be authenticated. Content authentication should		also needs to be authenticated. Content authentication should
	support the models where:		support the models where:
	- authentication for multicast content is outsourced to the		- authentication for multicast content is outsourced to the
	NSP.		NSP.
	- authentication for multicast content access is operated by		- authentication for multicast content access is operated by
	the CP		the CP
	5.2 IP Multicast-based Content Delivery Service (CDS): CP and NSP are		5.2 IP Multicast-based Content Delivery Service (CDS): CP and NSP are
	skipping to change at page 21, line 10		skipping to change at page 21, line 10
	+----------+ +----------+ +----------+		+----------+ +----------+ +----------+
	User A User B User C		User A User B User C
	Fig.3 Example of CDS network configuration		Fig.3 Example of CDS network configuration
	6. Acknowledgments		6. Acknowledgments
	The authors of this draft would like to express their appreciation		The authors of this draft would like to express their appreciation
	to Pekka Savola of Netcore Ltd., Daniel Alvarez, and Toerless		to Pekka Savola of Netcore Ltd., Daniel Alvarez, and Toerless
	Eckert of Cisco Systems, Sam Sambasivan of AT&T, Sanjay Wadhwa of		Eckert of Cisco Systems, Sam Sambasivan of AT&T, Sanjay Wadhwa of
	Juniper, Tom Anschutz and Steven Wright of BellSouth, Nicolai		Juniper, Tom Anschutz and Steven Wright of BellSouth, Nicolai
	Leymann of T-Systems, Carlos Garcia Braschi of Telefonica		Leymann of T-Systems, Carlos Garcia Braschi of Telefonica Empresas,
	Empresas, Marshall Eubanks of Multicast Techno, Stephen Rife of		Marshall Eubanks of Multicast Techno, Stephen Rife of NTT and
	NTT and David Meyer in his role as mboned WG chair, as well as		David Meyer in his role as mboned WG chair, as well as their
	their thanks to the participants of the MBONED WG in general.		thanks to the participants of the MBONED WG in general.
	Funding for the RFC Editor function is currently provided by the		Funding for the RFC Editor function is currently provided by the
	Internet Society.		Internet Society.
	7. IANA Considerations		7. IANA Considerations
	This memo does not raise any IANA consideration issues.		This memo does not raise any IANA consideration issues.
	8. Security Considerations		8. Security Considerations
	skipping to change at page 24, line 6		skipping to change at page 24, line 6
	Phone: +81 422 59 3617		Phone: +81 422 59 3617
	Email: ohta.hiroshi@lab.ntt.co.jp		Email: ohta.hiroshi@lab.ntt.co.jp
	Susheela Vaidya		Susheela Vaidya
	Cisco Systems, Inc.		Cisco Systems, Inc.
	170 W. Tasman Drive San Jose, CA 95134		170 W. Tasman Drive San Jose, CA 95134
	Phone: +1 408 525 1952		Phone: +1 408 525 1952
	Email: svaidya@cisco.com		Email: svaidya@cisco.com
	Full Copyright Statement		Full Copyright Statement
	Copyright (C) The IETF Trust (2007).		Copyright (C) The IETF Trust (2008).
	This document is subject to the rights, licenses and		This document is subject to the rights, licenses and
	restrictions contained in BCP 78, and except as set forth		restrictions contained in BCP 78, and except as set forth
	therein, the authors retain all their rights.		therein, the authors retain all their rights.
	"This document and the information contained herein are provided		Disclaimer
			This document and the information contained herein are provided
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	Intellectual Property		Intellectual Property
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	skipping to change at page 25, line 5		skipping to change at page 25, line 7
	use of such proprietary rights by implementers or users of this		use of such proprietary rights by implementers or users of this
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	The IETF invites any interested party to bring to its attention		The IETF invites any interested party to bring to its attention
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	required to implement this standard. Please address the		required to implement this standard. Please address the
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	Expiration
	This Internet-Draft will expire on March 22, 2008.
	Acknowledgement		Acknowledgement
	Funding for the RFC Editor function is currently provided by the		Funding for the RFC Editor function is currently provided by the
	Internet Society.		Internet Society.
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