SIP Trunking Case Study (Medtronic) Part 2
- 1. SIP Trunking Implementation Jim Allen Global Unified Communications Architect James.R.Allen@Medtronic.com
- 2. Lessons Learned • Address Network Readiness • Understand Pricing Models – Savings Vary Based on Site Dynamics (for us; Favors Sites Under 100 Users) • Get Comfortable with Risk (Savings Based on Elimination of Local PRIs) • Map ALL Call Flows 2 | MDT Confidential
- 3. Call Flow Mapping Medtronic IP & SIP Call Flow Verizon Voice PSTN Out Verizon Voice PSTN In Verizon Fax PSTN In Verizon Fax PSTN Out Conferencing Out Microsoft Voicemail Out Microsoft Voicemail In Verizon SBC Verizon SBC Verizon SBC Verizon SBC Intercall Verizon SBC MS UM Server G.711 G.711 G.729 G.729 G.729 G.711 Acme matches strip 003 and Called DID lookup via local route adds SDP with G.711 codec only No digits striped No digits prepended from Verizon table. Match call routes on net. No digit prepend from Verizon No digit prepend from Verizon No match routes to Vzb (HMR converts to EO Invite) G.711 ACME SBC ACME SBC ACME SBC ACME SBC ACME SBC Cisco CUBE G.711 Native RFC 2833 Call routed to cluster based on Route List Prepends 003 to all Call routed to cluster based on source SIP trunk or LRT lookup. Call covers to UM. New SIP invite Off cluster calls sent to Acme outbound DIDs for Fax calls No digits prepended source SIP trunk or LRT lookup. Faxes split off in specific region to created for UM using G.711 based G.711 Native RFC 2833 Codec based on cluster regions force G.711 on Region relationship G.729 G.729 G.729 G.729 Native RFC 2833 G.729 Native RFC 2833 G.729 Native RFC 2833 G.729 – Native RFC 2833 G.729 – Native RFC 2833 G.729 – Native RFC 2833 G.711 G.711 MTP MTP MTP IOS SW MTP SW G.711 IOS SW IOS SW Res Cluster Res Res Res G.729 G.711 G.729 G.729 Analog Analog Analog Analog Analog Analog GW GW GW GW GW GW 79X1 7936 79X1 7936 FAX FAX 79X1 7936 79X1 7936 MS UM Analog Analog Analog Analog Server Phone Phone Phone Phone 3 | MDT Confidential
- 4. Lessons Learned (Cont) • Outbound ANI Considerations (Masking) • Start With Non-Critical Applications • Understand Carrier SIP Requirements 4 | MDT Confidential
- 5. Delayed Vs. Early Offer Challenge Verizon today only supports SIP Early Offer Verizon Session Border Controllers ACME Session Border Controllers Tot Problem: Cisco Early Offer only supports G.711 on version 6.x and earlier. Media Termination Point are also required for every call. Call Manager Cluster MTP routes media Cisco IP path through Call Phone Manager Cluster or Media Gateway 5 | MDT Confidential
- 6. Delayed Vs. Early Offer Solution Verizon only supports SIP Early Offer today. Other vendors support Verizon Session Border varies. Controllers Solution: Acme SBC modifies SIP Invite from Call Manager using Header Manipulation Rule. Acme adds SDP converting it from Delayed to Early Offer. ACME Session Border SDP for voice calls includes G.711 & G.729.codecs. Controllers SDP for fax calls includes only G.711. Tot Cluster sends all SIP Invites as Delayed Offer allowing G.729 or G.711 codec negotiation. Call Manager Cluster Media path flows directly from IP phone to Acme SBC once media is Cisco IP Phone established. 6 | MDT Confidential
- 7. Lessons Learned (Cont) • Pilot and Test Extensively – Test ALL Variations • Local, National, International, Small Markets, Faxing • Voice mail & UM, Auto Attendants etc • Route Outbound First • Port DIDs Last – Most Difficult to Back Out • Define Capacity Strategy 7 | MDT Confidential
- 8. SIP Capacity Management 180 total concurrent calls PSTN Verizon Session Border provisioned Controllers Calls over 100 outbound from Twin Cities overflow to legacy PSTN Acme set to only allow 100 calls No restrictions set for PRIs outbound on Twin Cities trunk regional sites ACME Session Border Tot Controllers 140 concurrent calls provisioned on Twin Cities SIP Trunk Remote sites provisioned with 1 Twin Cities site used as call only. BEST allows burst of overflow protection PSTN 50 over. IP Gateways Cisco IP Cisco IP Cisco IP Cisco IP Cisco IP Cisco IP Cisco IP Cisco IP Cisco IP Phone Phone Phone Phone Phone Phone Phone Phone Phone Twin Cities Metro Area Remote Site Remote Site 8 | MDT Confidential
- 9. Questions 9 | MDT Confidential