ESN LLC v. Cisco Systems, Inc. et al

Filing 68

Plaintiff ESN, LLC's Opening Claim Construction Brief filed by ESN LLC. (Attachments: # 1 Exhibit A - Part 1, # 2 Exhibit A - Part 2, # 3 Exhibit B, # 4 Exhibit C, # 5 Exhibit D, # 6 Exhibit E)(McAndrews, Peter)

EXHIBIT C

Network Working Group Request for Comments: 3261 Obsoletes: 2543 Category: Standards Track

J. Rosenberg dynamicsoft H. Schulzrinne Columbia U. G. Camarillo Ericsson A. Johnston WorldCom J. Peterson Neustar R. Sparks dynamicsoft M. Handley ICIR E. Schooler AT&T June 2002

SIP: Session Initiation Protocol Status of this Memo This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited. Copyright Notice Copyright (C) The Internet Society (2002). Abstract This document describes Session Initiation Protocol (SIP), an application-layer control (signaling) protocol for creating, modifying, and terminating sessions with one or more participants. These sessions include Internet telephone calls, multimedia distribution, and multimedia conferences. SIP invitations used to create sessions carry session descriptions that allow participants to agree on a set of compatible media types. SIP makes use of elements called proxy servers to help route requests to the user's current location, authenticate and authorize users for services, implement provider call-routing policies, and provide features to users. SIP also provides a registration function that allows users to upload their current locations for use by proxy servers. SIP runs on top of several different transport protocols. All Rights Reserved.

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Standards Track

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RFC 3261

SIP: Session Initiation Protocol

June 2002

26.1.5 Denial of Service and Amplification ................. 26.2 Security Mechanisms ................................. 26.2.1 Transport and Network Layer Security ................ 26.2.2 SIPS URI Scheme ..................................... 26.2.3 HTTP Authentication ................................. 26.2.4 S/MIME .............................................. 26.3 Implementing Security Mechanisms .................... 26.3.1 Requirements for Implementers of SIP ................ 26.3.2 Security Solutions .................................. 26.3.2.1 Registration ........................................ 26.3.2.2 Interdomain Requests ................................ 26.3.2.3 Peer-to-Peer Requests ............................... 26.3.2.4 DoS Protection ...................................... 26.4 Limitations ......................................... 26.4.1 HTTP Digest ......................................... 26.4.2 S/MIME .............................................. 26.4.3 TLS ................................................. 26.4.4 SIPS URIs ........................................... 26.5 Privacy ............................................. 27 IANA Considerations ................................. 27.1 Option Tags ......................................... 27.2 Warn-Codes .......................................... 27.3 Header Field Names .................................. 27.4 Method and Response Codes ........................... 27.5 The "message/sip" MIME type. ....................... 27.6 New Content-Disposition Parameter Registrations ..... 28 Changes From RFC 2543 ............................... 28.1 Major Functional Changes ............................ 28.2 Minor Functional Changes ............................ 29 Normative References ................................ 30 Informative References .............................. A Table of Timer Values ............................... Acknowledgments ................................................ Authors' Addresses ............................................. Full Copyright Statement ....................................... 1 Introduction

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There are many applications of the Internet that require the creation and management of a session, where a session is considered an exchange of data between an association of participants. The implementation of these applications is complicated by the practices of participants: users may move between endpoints, they may be addressable by multiple names, and they may communicate in several different media - sometimes simultaneously. Numerous protocols have been authored that carry various forms of real-time multimedia session data such as voice, video, or text messages. The Session Initiation Protocol (SIP) works in concert with these protocols by

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Standards Track

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June 2002

enabling Internet endpoints (called user agents) to discover one another and to agree on a characterization of a session they would like to share. For locating prospective session participants, and for other functions, SIP enables the creation of an infrastructure of network hosts (called proxy servers) to which user agents can send registrations, invitations to sessions, and other requests. SIP is an agile, general-purpose tool for creating, modifying, and terminating sessions that works independently of underlying transport protocols and without dependency on the type of session that is being established. 2 Overview of SIP Functionality SIP is an application-layer control protocol that can establish, modify, and terminate multimedia sessions (conferences) such as Internet telephony calls. SIP can also invite participants to already existing sessions, such as multicast conferences. Media can be added to (and removed from) an existing session. SIP transparently supports name mapping and redirection services, which supports personal mobility [27] - users can maintain a single externally visible identifier regardless of their network location. SIP supports five facets of establishing and terminating multimedia communications: User location: determination of the end system to be used for communication; User availability: determination of the willingness of the called party to engage in communications; User capabilities: determination of the media and media parameters to be used; Session setup: "ringing", establishment of session parameters at both called and calling party; Session management: including transfer and termination of sessions, modifying session parameters, and invoking services. SIP is not a vertically integrated communications system. SIP is rather a component that can be used with other IETF protocols to build a complete multimedia architecture. Typically, these architectures will include protocols such as the Real-time Transport Protocol (RTP) (RFC 1889 [28]) for transporting real-time data and providing QoS feedback, the Real-Time streaming protocol (RTSP) (RFC 2326 [29]) for controlling delivery of streaming media, the Media

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