Commetrex Corporation FoIP Challenges in the Real World FoIP Interoperability Workshop San Francisco, November 10, 2008

Commetrex’ FoIP Cred 1999, Commetrex ships T.38 relay 2001, Commetrex invents terminating T , Commetrex opens T.38 Interop Lab 2005, BladeWare SIP-based fax media server 2007, Commetrex ships T.38 V3 2008, Commetrex ships T.38 w/ V.34

Interop Evolution Level I:T.38 Level II: SIP, gateway-to-gateway Level III:Service networks Level IV: Network-to-network

Level I: T.38 Interoperability Lab

Testing Partners Sonus Nuera Cisco Mediatrix Excel Lucent Etc.

G.711 Pass-Through Private or public network Jitter/delay/loss/PCM clock synchronization When is it successful? Enterprise LAN Metro networks Open Internet

Level II: Gateway-to-Gateway HMP fax media server Terminating T.38 G.711 pass-through SIP…nothing fancy BladeWare

Level III: Service Networks Homogeneous…private B2BUAs/application servers Proxy servers REINVITES Poor service-network architectures

Stage IV: Network-to-Network Access providers Backbone

Stage IV: VoIP Access Providers Gafachi Packet8 Cbeyond Bandwidth.com For example:

Backbone Carriers Global Crossing XO Communications Level(3) iBasis Inmarsat

Dealing With the Carrier SIP issues T.38 issues Registration/authentication When SBCs get into the act. G.711 vs T.38 Knowledge (How do you spell “fax”?)

SIP/T.38 Options Redundancy or FEC Redundancy depth ECM ? re-INVITEs when session timers are used (RFC4028)

FoIP-Specific SIP Considerations SBC 300-second half-duplex problem Session Timers (1300 sec)?

Network-to-Network

SIP Trunking SIPconnect Nailed-up IP Registration Authentication

A Need We See Communicate, y’all!

Proposal to Carriers: Open Up! Train your people Put network details on the Web Put access details on the Web Put FoIP details on the Web T.38 support T.38/SIP options Interop/compatibility requirements and testing

Call Centric.com