The configuration on our side has many options, including Diversion, to allow the most flexibility we can. We prefer to test against an actual circuit as delivered in a production environment. We run through our own test plan to determine what features are supported by the carrier/ISP, while they do the same on their side. At that point we have a configuration guide that is made available to our business partners. What happens many times is that the "lab" configuration doesn't mirror a deployed configuration, and issues arise. And LCR provides challenges a times as the new route passes through gateways that behave in different ways. Mark Stappenbeck Senior Manager, Business Development Allworx 300 Main Street East Rochester, NY 14445 585-421-5508 Office (585) 421-3853 Fax mstappenbeck at allworx.com www.allworx.com ??????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????? -----Original Message----- From: Alex Balashov [mailto:abalashov at evaristesys.com] Sent: Tuesday, October 02, 2012 9:40 AM To: Mark R Lindsey Cc: Stappenbeck, Mark; voiceops at voiceops.org Subject: Re: [VoiceOps] AT&T Flexible Reach I was thinking more of scenarios in which there is an edge element/administrative border which can perform header manipulations, particularly adding identifying headers, but can't mangle to the same extent that an SBC (with a B2BUA internally) can. As a company specialising largely in proxies for such applications, that's something that comes up in our radar a lot. We can debate the propriety of using a proxy for such an application, but regardless, it's commonly done, for reasons of throughput and cost. The problem, as you know, is that proxies are quite circumscribed in the aspects of a SIP message they can manipulate--at least, standards-compliant proxies. In a very real sense, UAs on two sides of a proxy are interoperating with each other, rather than with the proxy. This creates both philosophical questions ("what exactly is the CPE here?") and a orthogonal, sometimes turbulent approach in relation to Bellhead expectations about how trunking works. -- Alex Balashov - Principal Evariste Systems LLC 235 E Ponce de Leon Ave Suite 106 Decatur, GA 30030 Tel: +1-678-954-0670 Fax: +1-404-961-1892 Web: http://www.evaristesys.com/, http://www.alexbalashov.com/