SER and Microsoft OCS

Project Description

This is a how to guide on using SER to redirect SIP traffic from One Microsoft OCS Mediation Server to Many SIP gateways.

Currently Microsoft requires a one to one relationship between an OCS Mediation Server and a SIP gateway. SER can be used to redirect SIP traffic from one OCS Mediation Server to different SIP gateways based on the Call To SIP URI.

Please Note - No RTP traffic passes through the SER Server.

Other Mods and Hacks -

Project Goals

  • One OCS Mediation routing to Many SIP Gateways - Yes
  • Outbound from OCS Call Completion - Yes
  • Inbound into OCS Call Completion - Yes - Does not route through SER
  • Far End/Telephone Disconnect/Hangup - Yes - Does not route through SER
  • Near End/OCS Disconnect/Hangup - Yes - Does route through SER

Future Project Goals

  • MySQL database lookup to modify Call To SIP URI
    • A database lookup would simplify the manipulation of Call To SIP URI's by performing this step inside IpTel SER instead at the various SIP Gateways

Legend / Key

IpTel SER Server
  • IP address -
OCS Mediation Server
  • IP address -
Dialogic Gateway 1 - Chicago IL
  • IP address -
Dialogic Gateway 2 - Dallas TX
  • IP address -
Dialogic Gateway 3 - St Louis MO
  • IP address -

Call Flow - Simplified


SER Configuration File



Microsoft OCS Mediation Server Configuration

PSTN Gateway next hop
  • IP address - - IpTel SER Server

Dialogic SIP Gateway Configuration

Gateway - Gateway Routing Tab - VoIP Endpoint ID
  • IP address - - IpTel SER Server
  • IP address - - OCS Mediation Server

Dial Plan - Inbound TDM Routing Tab - Outbound VoIP Information
  • URI - - OCS Mediation Server

Visits - 28310
Created by: voipen, Last modification: Mon 24 of Mar, 2008 (18:47 UTC)
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