[SIPForum-discussion] FoIP Task Group Achieves Milestone with the Publication of IETF RFC 6913

Tue May 14 17:06:56 UTC 2013

SIP Forum's Fax over IP Task Group Achieves Milestone with the Publication
of IETF RFC 6913 

RFC 6913, "Indicating Fax over IP Capability in the Session Initiation
Protocol (SIP)," enables intelligent FoIP routing for International faxing
by introducing a new "sip.fax" media feature tag, and is a direct outcome of
the SIP Forum's global Interop testing effort with the i3 Forum

North Andover, Mass. (May 14, 2013) - The SIP Forum announced today its Fax
over IP (FoIP) Task Group has achieved a significant milestone in its
mission to improve international IP fax transport services with the
publication of  <http://www.rfc-editor.org/rfc/rfc6913.txt> RFC 6913 - a new
Internet Engineering Task Force (IETF) RFC that introduces a new "sip.fax"
media feature tag that aims to enable the intelligent routing of
International faxes and greatly improve the reliability of International
faxing services. 

RFC 6913, co-authored by David Hanes, Kevin Fleming and Gonzalo Salgueiro,
defines and registers with IANA a new "fax" media feature tag for use with
the Session Initiation Protocol (SIP).  Currently, fax calls are
indistinguishable from voice calls at call initiation.  Consequently, fax
calls can be routed to SIP user agents that are not fax capable.  A "fax"
media feature tag implemented in conjunction with caller preferences allows
for early advertisement of fax capabilities and consequently, more
intelligent fax call routing.

Carriers have long struggled with the quality and reliability of
international IP faxing using the T.38 fax protocol in SIP networks - a
critical challenge for global service providers transitioning from a TDM to
an IP-based network infrastructure. With the new "sip.fax" media feature
tag, service providers worldwide have a new tool available to them that will
allow for standardized, well-defined and optimized intelligent routing
policies whereby they can selectively direct FoIP calls over qualified FoIP
routes. RFC 6913 is intended to enable a standards-based framework that
eliminates implementation-dependent variability and to support successful
end-to-end transmission of international fax calls between networks.

"Using RFC 6913, carriers can implement more intelligent and selective
routing practices for IP fax calls.  Based on the results of our extensive
joint testing with i3 Forum carriers from around the globe, this ability to
route fax calls down fax-optimized routes is especially critical in high
delay environments like international tandem-carrier routes with one or more
IP-to-TDM conversion points.  Implementing these improvements to FoIP should
help address the root causes of current transmission problems and move the
FoIP Task Group a giant step closer towards achieving its goal of making
global IP faxing reliable in 2013," said Gonzalo Salgueiro, SIP Forum FoIP
Task Group Chair.

SIP Forum FoIP Task Group

The  <http://www.sipforum.org/content/view/310/252/> SIP Forum's FoIP Task
Group is chartered with improving the quality and reliability of FoIP in SIP
networks, particularly the inter-carrier use of FoIP. First launched in late
2008 to address the technical and interoperability challenges involving the
transmission of fax documents over a SIP-enabled network, the group outlined
some of the key issues in its 2009 FoIP Problem Statement, and the
publication of the T.38 SIP-SDP Problem Statement.

FoIP Task Group leadership includes: Chair Gonzalo Salgueiro, Technical
Leader at Cisco; Marc Robins, President and Managing Director of the SIP
Forum; and Max Schroeder, Sr. VP. FaxCore, who serves as Task Group Whip.

In addition, Mike Coffee, CEO of Commetrex and former co-chair of the FoIP
Task Group, was a key contributor in the formation, planning and execution
of the groundbreaking joint testing program with the i3 Forum.  His
leadership and guidance were instrumental in making this multi-year
coordinated effort with carriers from around the globe the most
comprehensive attempt to identify and resolve the many challenges with
international FoIP.

SIP Forum-i3 Forum Joint Testing Program

In 2011, the SIP Forum and  <http://www.i3forum.org/> i3 Forum joined forces
to develop a new comprehensive testing program for carrier-based FoIP. The
goal was to identify and qualify transmission impairments and
interoperability challenges that arose in IP-based networks as the T.38
protocol became more widely deployed across carrier and enterprise networks.

"The joint testing initiative involved 12 carriers and marked the first time
the global carrier community has come together with a holistic approach to
solving this problem," said Marc Robins, SIP Forum President and Managing
Director.  

To that end, i3 Forum carriers volunteered to participate in two testing
phases. Task group members installed a fax server at each carrier's location
and conducted fax broadcast tests over a 14-week period. 

Phase I of the testing identified consistent internetworking IP fax issues
between SIP and SS7 networks. "FoIP calls transmitted internationally, using
tandem-carrier connections between SIP networks and SS7 carrier networks,
and utilizing least-cost routing methods, failed 50 percent of the time - a
very high rate," said Max Schroeder, FoIP TG Whip.  "So we decided to look
more closely at the routing issue and forensically examine the least-cost
routing of fax messages." 

The Phase II testing was conducted over a five-month period beginning in the
fall of 2011 and into early 2012. The purpose of this testing effort was to
more closely examine the question of FoIP-qualified routing.  Sixteen
carriers participated and worked in pairs to trace FoIP calls end-to-end and
identify the errors, exploring more closely the full routing information for
each call.  

"The findings conclusively showed that T.38 fax calls between IP and legacy
SS7 carrier networks, using existing least-cost-routing methods, had a
consistently high failure rate, unlike faxes that employed "intelligent
routing" policies," Schroeder said.

The Phase I and Phase II testing results and analysis provided the basis for
the FoIP Task Group's technical and design recommendation to the IETF and
the technical community at large.

*************************

Marc Robins

President and Managing Director

SIP Forum

 <http://www.sipforum.org/> http://www.sipforum.org

Mobile: 203-829-6307

SkypeMe! marcrobins

Chief Technology Evangelism Officer

Robins Consulting Group (RCG)

info at robinsconsult.com

 <http://www.robinsconsult.com/> http://www.robinsconsult.com

*************************

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://sipforum.org/pipermail/discussion/attachments/20130514/06f2e98e/attachment-0002.html>