RFC 2871 (rfc2871) - Page 2 of 25

A Framework for Telephony Routing over IP

RFC 2871                     TRIP Framework                    June 2000


   9.1    Gateways and Location Servers .......................   16
   9.2    Location Server to Location Server ..................   16
   9.2.1  Nature of Exchanged Information .....................   17
   9.2.2  Quality of Service ..................................   18
   9.2.3  Cost Information ....................................   19
   10     The Front End .......................................   19
   10.1   Front End Customers .................................   19
   10.2   Front End Protocols .................................   20
   11     Number Translations .................................   21
   12     Security Considerations .............................   22
   13     Acknowledgments .....................................   23
   14     Bibliography ........................................   23
   15     Authors' Addresses ..................................   24
   16     Full Copyright Statement ............................   25

1 Introduction

   This document serves as a framework for Telephony Routing over IP
   (TRIP), which supports the discovery and exchange of IP telephony
   gateway routing tables between providers. The document defines the
   problem of telephony routing exchange, and motivates the need for the
   protocol. It presents an architectural framework for TRIP, defines
   terminology, specifies the various protocol elements and their
   functions, overviews the services provided by the protocol, and
   discusses how it fits into the broader context of Internet telephony.

2 Terminology

   We define the following terms. Note that there are other definitions
   for these terms, outside of the context of gateway location. Our
   definitions aren't general, but refer to the specific meaning here:

     Gateway: A device with some sort of circuit switched network
        connectivity and IP connectivity, capable of initiating and
        terminating IP telephony signaling protocols, and capable of
        initiating and terminating telephone network signaling
        protocols.

     End User: The end user is usually (but not necessarily) a human
        being, and is the party who is the ultimate initiator or
        recipient of calls.

     Calling Device: The calling device is a physical entity which has
        IP connectivity. It is under the direction of an end user who
        wishes to place a call. The end user may or may not be directly
        controlling the calling device. If the calling device is a PC,





Rosenberg & Schulzrinne      Informational