1. Keeping cost-effectiveness in mind, TTBS delivered SIP Trunk over Ethernet with SDH ring architecture.
From the Last mile, SIP Trunk was terminated over the SBC.
2. The 4,000 DIDs were split equally between the two trunks.
3. To achieve 100% concurrency, bandwidth for both trunks supported the aggregate of SIP 1 and SIP 2.
4. TTBS SIP Trunk is a P2P circuit with /30 IP address assigned by TATA. The same IP address was assigned to the customer PBX’s NIC interface.
5. The codec on both trunks was configured to comply with the G.711-A law.
6. The Dual-Tone-Multi-Frequency was set at RFC 2833.
7. “P-Preferred-Identity” header was included in all SIP INVITEs for correct DID CLIP display on the outgoing calls.
8. DID number sending (DNIS) on SIP INVITE “To” header on the incoming calls .
9. TTBS ensured the keep-alive mechanism through SIP OPTIONS. The expected response was SIP 400 Ok from the CPE device.
10. The following parameters were provided by TTBS: Customer IP (configured at the SBC’s NIC port) Gateway IP, SIP Server, IP Subnet Mask, Username, Password and DID Range