. NENA VoIP Technical Committee VoIP Characteristics Technical Information Document NENA 08-503 - VoIP Characteristics Technical Information Document (TID) Issue 1, June 10, 2004 Prepared by: National Emergency Number Association (NENA) VoIP Technical Committee - VoIP Characteristics Working Group Published by NENA Printed in USA NENA VoIP Characteristics Technical Information Document NENA 08-503 June 10, 2004 (Original) NENA TECHNICAL INFORMATION DOCUMENT NOTICE This Technical Information Document (TID) is published by the National Emergency Number Association (NENA) as an information source for the designers and manufacturers of systems that are used for the purpose of processing emergency calls. It is not intended to provide complete design specifications or parameters or to assure the quality of performance for systems that process emergency calls. NENA reserves the right to revise this TID for any reason including, but not limited to, conformity with criteria or standards promulgated by various agencies, utilization of advances in the state of the technical arts or to reflect changes in the design of network interface or services described herein. It is possible that certain advances in technology will precede these revisions. Therefore, this TID should not be the only source of information used. NENA members are advised to contact their Telecommunications Carrier representative to ensure compatibility with the 9-1-1 network. Patents may cover the specifications, techniques or network interface/system characteristics disclosed herein. No license expressed or implied is hereby granted. This document is not to be construed as a suggestion to any manufacturer to modify or change any of its products, nor does this document represent any commitment by NENA or any affiliate thereof to purchase any product whether or not it provides the described characteristics. This document has been prepared solely for the voluntary use of E9-1-1 Service System Providers, network interface and system vendors, participating telephone companies, etc. By using this document, the user agrees that NENA will have no liability for any consequential, incidental, special, or punitive damages arising from use of the document. NENA’s Committees have developed this document. Recommendations for change to this document may be submitted to: National Emergency Number Association 1700 Diagonal Rd, Suite 500 Alexandria, VA 22314 202.466.4911 or [email protected] Page 2 of 30 NENA VoIP Characteristics Technical Information Document NENA 08-503 June 10, 2004 (Original) Acknowledgments: This document has been developed by the National Emergency Number Association (NENA) VoIP Technical Committee. The following industry experts and their companies are recognized for their contributions in development of this document. Members Company Henning Schulzrinne Columbia University Jonathan Flack Cox Communications Deborah Stone Intrado Lawrence Gowin Level 3 Communications Brian Rosen Marconi Mike Aprile – WG Leader Red Sky Technologies, Inc. Nate Wilcox – VTC Chair Vermont Enhanced 9-1-1 Greg Welenson Vonage Holdings, Inc. Larry Short Page 3 of 30 NENA VoIP Characteristics Technical Information Document NENA 08-503 June 10, 2004 (Original) Table of Contents 1 EXECUTIVE OVERVIEW .............................................................................................................................. 6 1.1 PURPOSE AND SCOPE OF DOCUMENT .................................................................................................................... 6 1.2 REASON FOR ISSUE ............................................................................................................................................... 6 1.3 REASON FOR REISSUE ........................................................................................................................................... 6 1.4 RECOMMENDATION FOR STANDARDS DEVELOPMENT WORK ............................................................................... 6 1.5 COST FACTORS ..................................................................................................................................................... 6 1.6 ACRONYMS/ABBREVIATIONS ................................................................................................................................ 6 2 TECHNICAL DESCRIPTION ......................................................................................................................... 7 2.1 TCP/IP PRIMER .................................................................................................................................................... 7 2.1.1 What is TCP/IP made of? ........................................................................................................................... 7 2.1.2 Application Layer ....................................................................................................................................... 7 2.1.3 Transport Layer .......................................................................................................................................... 8 2.1.4 Internet Layer ............................................................................................................................................. 8 2.1.5 Physical Layer ............................................................................................................................................ 8 2.2 DECENTRALIZED IMPLEMENTATION ..................................................................................................................... 9 2.3 PHYSICAL MEDIA INDEPENDENCE ........................................................................................................................ 9 2.4 NETWORK REQUIREMENTS ................................................................................................................................... 9 2.4.1 Latency ..................................................................................................................................................... 10 2.4.2 Jitter.......................................................................................................................................................... 10 2.4.3 Packet Loss ............................................................................................................................................... 10 2.4.4 General Guidelines ................................................................................................................................... 10 2.4.5 Quality of Service (QoS) ........................................................................................................................... 10 2.5 MEDIA TYPES ..................................................................................................................................................... 11 2.5.1 Data .......................................................................................................................................................... 12 2.5.2 Voice ......................................................................................................................................................... 12 2.5.3 Video ......................................................................................................................................................... 12 2.6 SEPARATION OF CALL CONTROL AND MEDIA TRANSPORT ................................................................................. 12 2.7 VIRTUAL LOCATIONS AND MOBILITY ................................................................................................................. 12 2.8 IP TELEPHONY ARCHITECTURE OPTIONS ............................................................................................................ 13 2.8.1 Trunk Replacement ................................................................................................................................... 14 2.8.2 Hybrid (hop-on/hop-off) ........................................................................................................................... 15 2.8.3 Direct, end-to-end IP connections ............................................................................................................ 15 2.9 METHODS OF USAGE ........................................................................................................................................... 15 2.9.1 Replacing the PBX .................................................................................................................................... 15 2.9.2 Extending the PBX .................................................................................................................................... 15 2.9.3 IP Centrex ................................................................................................................................................. 16 2.9.4 Residential Service ................................................................................................................................... 16 2.10 HARDWARE COMPONENTS ............................................................................................................................. 17 2.10.1 IP End-Points (i.e. phones, PCs, etc.) .................................................................................................. 17 2.10.2 Access Gateways .................................................................................................................................