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Technical Specifications for Business Class
SIP Trunks

Time Warner Cable (TWC) Business Class SIP Trunks offer an IP-based, voice only, trunk service using Session Initiation Protocol (SIP) to connect an IP PBX to the PSTN.  A Time Warner Cable owned and managed Enterprise SIP Gateway (ESG) is then installed at a customer’s site.  The ESG serves as a gateway and demarcation point between a customer’s IP PBX and the TWC voice network.  The ESG also enables Time Warner Cable Business Class to remotely monitor and manage the SIP Trunk service performance.  SIP Trunks are provided via an Ethernet connection over fiber and hybrid fiber coax (HFC).  If provided over HFC, Time Warner Cable Business Class will also install a cable modem to support the service.

Business Class SIP Trunk Specifications

  • Customer Premise Equipment - ESG for fiber access sites; Cable modem also installed for HFC access sites;
  • ESG LAN Configuration - Bandwidth: 10Mbps, 100Mbps or 1Gbps (100 Mbps recommended); Duplex: Full or Auto (Full recommended); Registration: Static or DHCP (Static recommended)



  • Physical Space Requirements - Rack Shelf to fit Gateway: 2.5” (H) x 7.8”(W) x 6.0” (D); 110 volt AC Power outlet (3); Site Temp between 32◦ and 104◦ with adequate air circulation
  • Supported CODECs - G.711; T.38 for Fax; DTMF RFC2833