A new Request for Comments is now available in online RFC libraries. RFC 7092 Title: A Taxonomy of Session Initiation Protocol (SIP) Back-to-Back User Agents Author: H. Kaplan, V. Pascual Status: Informational Stream: IETF Date: December 2013 Mailbox: hadriel.kaplan@oracle.com, victor.pascual@quobis.com Pages: 10 Characters: 22085 Updates/Obsoletes/SeeAlso: None I-D Tag: draft-ietf-straw-b2bua-taxonomy-03.txt URL: http://www.rfc-editor.org/rfc/rfc7092.txt In many SIP deployments, SIP entities exist in the SIP signaling path between the originating and final terminating endpoints, which go beyond the definition of a SIP proxy, performing functions not defined in Standards Track RFCs. The only term for such devices provided in RFC 3261 is for a Back-to-Back User Agent (B2BUA), which is defined as the logical concatenation of a SIP User Agent Server (UAS) and User Agent Client (UAC). There are numerous types of SIP B2BUAs performing different roles in different ways; for example, IP Private Branch Exchanges (IPBXs), Session Border Controllers (SBCs), and Application Servers (ASs). This document identifies several common B2BUA roles in order to provide taxonomy other documents can use and reference. This document is a product of the Sip Traversal Required for Applications to Work Working Group of the IETF. INFORMATIONAL: This memo provides information for the Internet community. It does not specify an Internet standard of any kind. Distribution of this memo is unlimited. This announcement is sent to the IETF-Announce and rfc-dist lists. To subscribe or unsubscribe, see http://www.ietf.org/mailman/listinfo/ietf-announce http://mailman.rfc-editor.org/mailman/listinfo/rfc-dist For searching the RFC series, see http://www.rfc-editor.org/search/rfc_search.php For downloading RFCs, see http://www.rfc-editor.org/rfc.html Requests for special distribution should be addressed to either the author of the RFC in question, or to rfc-editor@rfc-editor.org. Unless specifically noted otherwise on the RFC itself, all RFCs are for unlimited distribution. The RFC Editor Team Association Management Solutions, LLC