Internet Engineering Task Force James M. Polk Internet Draft Cisco Systems Expiration: Sept 3rd, 2003 File: draft-polk-ieprep-scenarios-03.txt IEPREP Telephony Topology Terminology March 3rd, 2003 Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress". The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. Abstract This document defines the topology naming conventions that are to be used in reference to IEPREP phone calls. These naming conventions should be used to focus the IEPREP Working Group during discussions and when writing requirements, gap analysis and other solutions documents. Polk IEPREP Telephony Topology Terminology Page 1 Internet Draft draft-polk-ieprep-scenarios-03.txt Mar 3rd, 2003 Table of Contents Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.0 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.2 Changes from previous versions . . . . . . . . . . . . . . . . . . 2 1.3 Terms and Definitions . . . . . . . . . . . . . . . . . . . . . . 3 2.0 IEPREP Topologies . . . . . . . . . . . . . . . . . . . . . . . . 3 2.1 Topology "IP Bridging" . . . . . . . . . . . . . . . . . . . . . . 3 2.2 Topology "IP at the Start" . . . . . . . . . . . . . . . . . . . . 4 2.3 Topology "IP at the End" . . . . . . . . . . . . . . . . . . . . . 4 2.4 Topology "End-to-End IP" . . . . . . . . . . . . . . . . . . . . . 5 3.0 Security Considerations . . . . . . . . . . . . . . . . . . . . . . 5 4.0 IANA Considerations . . . . . . . . . . . . . . . . . . . . . . . . 5 5.0 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . 5 6.0 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 7.0 Authors Information . . . . . . . . . . . . . . . . . . . . . . . . 6 1.0 Introduction This document defines the topology naming conventions that are to be used in reference to IEPREP phone calls. These naming conventions should be used to focus the IEPREP Working Group during discussions and when writing requirements, gap analysis and other solutions documents. There has been much confusion on the IEPREP list as well as within each meeting about the topologies IEPREP is considering. Hopefully this document will give each reader and author a reference set of named architectures. This memo attempts to be agnostic with regard to IP signaling or control protocols (SIP, MEGACO, etc), as well as any underlying QOS mechanisms (Diffserv, RSVP, NSIS, etc). 1.1 Motivation Simply put, to get everyone referencing the same (named) topologies in order to have useful and less confusing dialog to further this working group's efforts. 1.2 Changes From Previous Versions Changes from -00 to -01 This version greatly reduces the text of the overall document by removing all discussion of requirements and authentication & authorization. This is Polk IEPREP Telephony Topology Terminology Page 2 Internet Draft draft-polk-ieprep-scenarios-03.txt Mar 3rd, 2003 not a requirements document (therefore shouldn't state any), and the A&A text/discussion for each of the topologies, though necessary within the WG, has been moved to another "ieprep-topology-implications" document. Changes from -01 to -02 Cleaned up minor omissions discovered that weren't omitted from the -00 to -01 change. Took out the paragraph following Figure 2 (section 2.2) referring to where ETS aware devices should be. 1.3 Terms and Definitions The following acronyms need to be exploded for clarity: CSN = Circuit Switched Network GW = Gateway (CSN to IP, or IP to CSN) 2.0 IEPREP Topologies There are 4 often mentioned, but very little documented topologies discussed within this WG's efforts so far. The following subsections name and describe each of the topologies. The 4 topologies are (quickly): Topology "IP Bridging" Topology "IP at the Start" Topology "IP at the End" Topology "End-to-End IP" 2.1 Topology "IP Bridging" This topology is sometimes known as "IP in the Middle" of two CSNs. In this topology, a CSN phone of any type initiates (dials) a call to another CSN phone with an IP core between the two CSNs. Polk IEPREP Telephony Topology Terminology Page 3 Internet Draft draft-polk-ieprep-scenarios-03.txt Mar 3rd, 2003 This topology should simplistically look like this: Circuit Internet Circuit Switched IP or IP Switched Network Ingress IP Segment Egress Network -----------+ +--------------+ +----------- | +----+ | IP | +----+ | CSN | | | | | | | | CSN Phone ------->| GW |----------------------->| GW |-------->Phone | | | | | | | | | +----+ | | +----+ | -----------+ +--------------+ +----------- Figure 1. Topology "IP Bridging" 2.2 Topology "IP at the Start" This topology has the initiating party placing (dialing) the call from an IP Phone (PDA or computer), and the called party residing in the CSN. Internet Circuit or CSN Switched IP Segment Ingress Network -------------------+ +--------------- | +----+ | IP | | | | CSN Phone ------------------>| GW |--------> Phone | | | | | +----+ | -------------------+ +--------------- Figure 2. Topology "IP at the Start" 2.3 Topology "IP at the End" This topology has the calling party placing the call from a CSN phone, and the called party being in an IP network. Circuit Internet Switched CSN or Network Egress IP Segment -------------------+ +--------------- | +----+ | CSN | | | | IP Phone ------------------>| GW |--------> Phone | | | | | +----+ | -------------------+ +--------------- Figure 3. Topology "IP at the End" Polk IEPREP Telephony Topology Terminology Page 4 Internet Draft draft-polk-ieprep-scenarios-03.txt Mar 3rd, 2003 2.4 Topology "End-to-End IP" This topology has no circuit switched sections in the call path. Internet or IP Network +-----------------------------------------+ | | +---------+ +-----------+ | | | IP IP | | Phone --------------------------------------------> Phone | | | +---------+ +-----------+ | | +-----------------------------------------+ Figure 4. Topology "End to End IP" Although shown as one large IP cloud here, the Internet is composed of a series of loosely connected IP domains. An End-to-End IP call will likely traverse a number of these domains and/or multiple network providers, which may impact the call. 3.0 Security Considerations This document merely suggests a common naming convention within IEPREP WG discussions, therefore there are no special security considerations. 4.0 IANA Considerations There are no IANA considerations within this document 5.0 Acknowledgements To Scott Bradner, Kimberly King and Mike Pierce for their comments and suggestions 6.0 References none at this moment Polk IEPREP Telephony Topology Terminology Page 5 Internet Draft draft-polk-ieprep-scenarios-03.txt Mar 3rd, 2003 7.0 Authors Information James M. Polk Cisco Systems 2200 East President George Bush Turnpike Richardson, Texas 75082 USA jmpolk@cisco.com "Copyright (C) The Internet Society (2003). All Rights Reserved. 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This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE." The Expiration date for this Internet Draft is: June 3rd, 2003 Polk IEPREP Telephony Topology Terminology Page 6