draft-ietf-cdi-model-00.txt		draft-ietf-cdi-model-01.txt
	Network Working Group M. Day		Network Working Group M. Day
	Internet-Draft Cisco		Internet-Draft Cisco
	Expires: August 23, 2002 B. Cain		Expires: August 23, 2002 B. Cain
	Cereva		Storigen
	G. Tomlinson		G. Tomlinson
	CacheFlow		CacheFlow
	P. Rzewski		P. Rzewski
	Inktomi		Inktomi
	February 22, 2002		February 22, 2002
	A Model for Content Internetworking (CDI)		A Model for Content Internetworking (CDI)
	draft-ietf-cdi-model-00.txt		draft-ietf-cdi-model-01.txt
	Status of this Memo		Status of this Memo
	This document is an Internet-Draft and is in full conformance with		This document is an Internet-Draft and is in full conformance with
	all provisions of Section 10 of RFC2026.		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.
	skipping to change at page 2, line 14		skipping to change at page 2, line 14
	Table of Contents		Table of Contents
	1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3		1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
	2. Content Networks . . . . . . . . . . . . . . . . . . . . . . 4		2. Content Networks . . . . . . . . . . . . . . . . . . . . . . 4
	2.1 Problem Description . . . . . . . . . . . . . . . . . . . . 4		2.1 Problem Description . . . . . . . . . . . . . . . . . . . . 4
	2.2 Caching Proxies . . . . . . . . . . . . . . . . . . . . . . 5		2.2 Caching Proxies . . . . . . . . . . . . . . . . . . . . . . 5
	2.3 Server Farms . . . . . . . . . . . . . . . . . . . . . . . . 6		2.3 Server Farms . . . . . . . . . . . . . . . . . . . . . . . . 6
	2.4 Content Distribution Networks . . . . . . . . . . . . . . . 7		2.4 Content Distribution Networks . . . . . . . . . . . . . . . 7
	2.4.1 Historic Evolution of CDNs . . . . . . . . . . . . . . . . . 9		2.4.1 Historic Evolution of CDNs . . . . . . . . . . . . . . . . . 9
	2.4.2 Describing CDN Value: Reach and Scale . . . . . . . . . . . 9		2.4.2 Describing CDN Value: Scale and Reach . . . . . . . . . . . 9
	3. Content Network Model Terms . . . . . . . . . . . . . . . . 11		3. Content Network Model Terms . . . . . . . . . . . . . . . . 11
	4. Content Internetworking . . . . . . . . . . . . . . . . . . 14		4. Content Internetworking . . . . . . . . . . . . . . . . . . 14
	5. Content Internetworking Model Terms . . . . . . . . . . . . 15		5. Content Internetworking Model Terms . . . . . . . . . . . . 15
	6. Security Considerations . . . . . . . . . . . . . . . . . . 18		6. Security Considerations . . . . . . . . . . . . . . . . . . 18
	7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 19		7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 19
	References . . . . . . . . . . . . . . . . . . . . . . . . . 20		References . . . . . . . . . . . . . . . . . . . . . . . . . 20
	Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 21		Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 21
	Full Copyright Statement . . . . . . . . . . . . . . . . . . 22		Full Copyright Statement . . . . . . . . . . . . . . . . . . 22
	1. Introduction		1. Introduction
	skipping to change at page 9, line 41		skipping to change at page 9, line 41
	popular servers). However, both in principle and increasingly in		popular servers). However, both in principle and increasingly in
	practice, a CDN can support the delivery of any digital content --		practice, a CDN can support the delivery of any digital content --
	including various forms of streaming media. For a streaming media		including various forms of streaming media. For a streaming media
	CDN (or media distribution network or MDN), the surrogates may be		CDN (or media distribution network or MDN), the surrogates may be
	operating as splitters (serving out multiple copies of a stream).		operating as splitters (serving out multiple copies of a stream).
	The splitter function may be instead of, or in addition to, a role as		The splitter function may be instead of, or in addition to, a role as
	a caching proxy. However, the basic elements defined in this model		a caching proxy. However, the basic elements defined in this model
	are still intended to apply to the interconnection of content		are still intended to apply to the interconnection of content
	networks that are distributing streaming media.		networks that are distributing streaming media.
	2.4.2 Describing CDN Value: Reach and Scale		2.4.2 Describing CDN Value: Scale and Reach
	There are two fundamental elements that give a CDN value: outsourcing		There are two fundamental elements that give a CDN value: outsourcing
	infrastructure and improved content delivery. A CDN allows multiple		infrastructure and improved content delivery. A CDN allows multiple
	surrogates to act on behalf of an orgin server, therefore removing		surrogates to act on behalf of an orgin server, therefore removing
	the delivery of content from a centralized site to multiple and		the delivery of content from a centralized site to multiple and
	(usually) highly distributed sites. We refer to increased aggregate		(usually) highly distributed sites. We refer to increased aggregate
	infrastructure size as "scale." In addition, a CDN can be constructed		infrastructure size as "scale." In addition, a CDN can be constructed
	with copies of content near to end users, overcoming issues of		with copies of content near to end users, overcoming issues of
	network size, network congestion, and network failures. We refer to		network size, network congestion, and network failures. We refer to
	increased diversity of content locations as "reach."		increased diversity of content locations as "reach."
	skipping to change at page 15, line 10		skipping to change at page 15, line 10
	participant than they could otherwise achieve. By using commonly		participant than they could otherwise achieve. By using commonly
	defined protocols for content internetworking, each content network		defined protocols for content internetworking, each content network
	can treat neighboring content networks as "black boxes", allowing		can treat neighboring content networks as "black boxes", allowing
	them to hide internal details from each other.		them to hide internal details from each other.
	5. Content Internetworking Model Terms		5. Content Internetworking Model Terms
	This section consists of the definitions of a number of terms used to		This section consists of the definitions of a number of terms used to
	refer to roles, participants, and objects involved in internetworking		refer to roles, participants, and objects involved in internetworking
	content networks. The purpose of this section is to identify common		content networks. The purpose of this section is to identify common
	terms and provide short definitions. A more detailed technical		terms and provide short definitions.
	discussion of these terms and their relationships appears in "Content
	Internetworking Architectural Overview" [4].
	ACCOUNTING INTERNETWORKING		ACCOUNTING INTERNETWORKING
	Interconnection of two or more ACCOUNTING SYSTEMS so as to enable		Interconnection of two or more ACCOUNTING SYSTEMS so as to enable
	the exchange of information between them. The form of ACCOUNTING		the exchange of information between them. The form of ACCOUNTING
	INTERNETWORKING required may depend on the nature of the		INTERNETWORKING required may depend on the nature of the
	NEGOTIATED RELATIONSHIP between the peering parties -- in		NEGOTIATED RELATIONSHIP between the peering parties -- in
	particular, on the value of the economic exchanges anticipated.		particular, on the value of the economic exchanges anticipated.
	ADVERTISEMENT		ADVERTISEMENT
	Information about resources available to other CONTENT NETWORKS,		Information about resources available to other CONTENT NETWORKS,
	skipping to change at page 16, line 30		skipping to change at page 16, line 28
	An ADVERTISEMENT from a CONTENT NETWORK's DISTRIBUTION SYSTEM to		An ADVERTISEMENT from a CONTENT NETWORK's DISTRIBUTION SYSTEM to
	potential CONTENT SOURCES, describing the capabilities of one or		potential CONTENT SOURCES, describing the capabilities of one or
	more CONTENT DESTINATIONS. Contrast with AREA ADVERTISEMENT,		more CONTENT DESTINATIONS. Contrast with AREA ADVERTISEMENT,
	CONTENT ADVERTISEMENT.		CONTENT ADVERTISEMENT.
	DISTRIBUTION INTERNETWORKING		DISTRIBUTION INTERNETWORKING
	Interconnection of two or more DISTRIBUTION SYSTEMS so as to		Interconnection of two or more DISTRIBUTION SYSTEMS so as to
	propagate CONTENT SIGNALS and copies of CONTENT to groups of		propagate CONTENT SIGNALS and copies of CONTENT to groups of
	SURROGATES.		SURROGATES.
			ENLISTED
			Describes a CONTENT NETWORK that, as part of a NEGOTIATED
			RELATIONSHIP, has accepted a DISTRIBUTION task from another
			CONTENT NETWORK, has agreed to perform REQUEST-ROUTING on behalf
			of another CONTENT NETWORK, or has agreed to provide ACCOUNTING
			data to another CONTENT NETWORK. Contrast with ORIGINATING.
	INJECTION		INJECTION
	A "send-only" form of DISTRIBUTION INTERNETWORKING that takes		A "send-only" form of DISTRIBUTION INTERNETWORKING that takes
	place from an ORIGIN to a CONTENT DESTINATION.		place from an ORIGIN to a CONTENT DESTINATION.
	INTER-		INTER-
	Describes activity that involves more than one CONTENT NETWORK		Describes activity that involves more than one CONTENT NETWORK
	(e.g. INTER-CDN). Contrast with INTRA-.		(e.g. INTER-CDN). Contrast with INTRA-.
	INTRA-		INTRA-
	Describes activity within a single CONTENT NETWORK (e.g. INTRA-		Describes activity within a single CONTENT NETWORK (e.g. INTRA-
	CDN). Contrast with INTER-.		CDN). Contrast with INTER-.
	NEGOTIATED RELATIONSHIP		NEGOTIATED RELATIONSHIP
	A relationship whose terms and conditions are partially or		A relationship whose terms and conditions are partially or
	completely established outside the context of CONTENT NETWORK		completely established outside the context of CONTENT NETWORK
	internetworking protocols.		internetworking protocols.
			ORIGINATING
			Describes a CONTENT NETWORK that, as part of a NEGOTIATED
			RELATIONSHIP, submits a DISTRIBUTION task to another CONTENT
			NETWORK, asks another CONTENT NETWORK to perform REQUEST-ROUTING
			on its behalf, or asks another CONTENT NETWORK to provide
			ACCOUNTING data. Contrast with ENLISTED.
	REMOTE CONTENT NETWORK		REMOTE CONTENT NETWORK
	A CONTENT NETWORK able to deliver CONTENT for a particular REQUEST		A CONTENT NETWORK able to deliver CONTENT for a particular REQUEST
	that is not the AUTHORITATIVE REQUEST-ROUTING SYSTEM for that		that is not the AUTHORITATIVE REQUEST-ROUTING SYSTEM for that
	REQUEST.		REQUEST.
	REQUEST-ROUTING INTERNETWORKING		REQUEST-ROUTING INTERNETWORKING
	Interconnection of two or more REQUEST-ROUTING SYSTEMS so as to		Interconnection of two or more REQUEST-ROUTING SYSTEMS so as to
	increase the number of REACHABLE SURROGATES for at least one of		increase the number of REACHABLE SURROGATES for at least one of
	the interconnected systems.		the interconnected systems.
	6. Security Considerations		6. Security Considerations
	There are no security-related issues related to the terms defined in		This document defines terminology and concepts for content
	this document. The technology of content internetworking does raise		internetworking. The terminology itself does not introduce any
	some security-related issues, and a detailed discussion of those		security-related issues. The implementation of content
	issues appears in "Content Internetworking Architectural Overview"		internetworking concepts does raise some security-related issues,
	[4].		which we identify in broad categories below. Other CDI documents
			will address their specific security-related issues in more detail.
			Secure relationship establishment: content internetworking must
			provide means to ensure that content networks are internetworking
			only with other content networks as intended. It must be possible to
			prevent unauthorized internetworking or spoofing of another network's
			identity.
			Secure content transfer: content internetworking must support
			content-network mechanisms that ensure both the integrity of content
			and the integrity of the delivery process, even when the delivering
			network is not the originating network. Content internetworking must
			allow for mechanisms to prevent theft or corruption of content.
			Secure meta-content transfer: content internetworking must support
			the movement of accurate, reliable, auditable information about costs
			and performance between content networks. Content internetworking
			must allow for mechanisms to prevent the diversion or corruption of
			accounting data and similar meta-content.
	7. Acknowledgements		7. Acknowledgements
	The authors acknowledge the contributions and comments of Fred		The authors acknowledge the contributions and comments of Fred
	Douglis (AT&T), Don Gilletti (CacheFlow), Markus Hoffmann (Lucent),		Douglis (AT&T), Don Gilletti (CacheFlow), Markus Hoffmann (Lucent),
	Barron Housel (Cisco), Barbara Liskov (Cisco), John Martin (Network		Barron Housel (Cisco), Barbara Liskov (Cisco), John Martin (Network
	Appliance), Nalin Mistry (Nortel Networks) Raj Nair (Cisco), Hilarie		Appliance), Nalin Mistry (Nortel Networks) Raj Nair (Cisco), Hilarie
	Orman (Volera), Doug Potter (Cisco), and Oliver Spatscheck (AT&T).		Orman (Volera), Doug Potter (Cisco), and Oliver Spatscheck (AT&T).
	[Note to RFC Editor: The last normative reference is [4], all		[Note to RFC Editor: The last normative reference is [3], all
	subsequent references starting with [5] can be deleted.]		subsequent references starting with [4] can be deleted.]
	References		References
	[1] Fielding, R., Gettys, J., Mogul, J., Frystyk, H., Masinter, L.,		[1] Fielding, R., Gettys, J., Mogul, J., Frystyk, H., Masinter, L.,
	Leach, P. and T. Berners-Lee, "Hypertext Transfer Protocol --		Leach, P. and T. Berners-Lee, "Hypertext Transfer Protocol --
	HTTP/1.1", RFC 2616, June 1999, <http://www.rfc-editor.org/rfc/		HTTP/1.1", RFC 2616, June 1999, <http://www.rfc-editor.org/rfc/
	rfc2616.txt>.		rfc2616.txt>.
	[2] Schulzrinne, H., Rao, A. and R. Lanphier, "Real Time Streaming		[2] Schulzrinne, H., Rao, A. and R. Lanphier, "Real Time Streaming
	Protocol", RFC 2326, April 1998, <http://www.rfc-editor.org/rfc/		Protocol", RFC 2326, April 1998, <http://www.rfc-editor.org/rfc/
	skipping to change at page 21, line 18		skipping to change at page 21, line 18
	Mark Stuart Day		Mark Stuart Day
	Cisco Systems		Cisco Systems
	1414 Massachusetts Avenue		1414 Massachusetts Avenue
	Boxborough, MA 01719		Boxborough, MA 01719
	US		US
	Phone: +1 978 936 1089		Phone: +1 978 936 1089
	EMail: markday@cisco.com		EMail: markday@cisco.com
	Brad Cain		Brad Cain
	Cereva Networks		Storigen Systems
	3 Network Drive		650 Suffolk Street
	Marlborough, MA 01752		Lowell, MA 01854
	US		US
	Phone: +1 508-787-5000		Phone: +1 978-323-4454
	EMail: bcain@cereva.com		EMail: bcain@storigen.com
	Gary Tomlinson		Gary Tomlinson
	CacheFlow, Inc.		CacheFlow, Inc.
	12034 134th Ct. NE Suite 201		12034 134th Ct. NE Suite 201
	Redmond, WA 98052		Redmond, WA 98052
	US		US
	Phone: +1 425 820 3009		Phone: +1 425 820 3009
	EMail: garyt@cacheflow.com		EMail: garyt@cacheflow.com
End of changes. 11 change blocks.
	19 lines changed or deleted		50 lines changed or added
This html diff was produced by rfcdiff 1.34. The latest version is available from http://tools.ietf.org/tools/rfcdiff/