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 – http://voipen.blogspot.com/

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 – 1.1.1.1

OCS Mediation Server

• IP address – 2.2.2.2

Dialogic Gateway 1 – Chicago IL

• IP address – 3.3.3.3

Dialogic Gateway 2 – Dallas TX

• IP address – 4.4.4.4

Dialogic Gateway 3 – St Louis MO

• IP address – 5.5.5.5

 

Call Flow – Simplified

SER Configuration File

ser.cfg

Microsoft OCS Mediation Server Configuration

PSTN Gateway next hop

• IP address – 1.1.1.1 – IpTel SER Server

 

Dialogic SIP Gateway Configuration

Gateway – Gateway Routing Tab – VoIP Endpoint ID

• IP address – 1.1.1.1 – IpTel SER Server
• IP address – 2.2.2.2 – OCS Mediation Server

Dial Plan – Inbound TDM Routing Tab – Outbound VoIP Information

• URI – 2.2.2.2 – OCS Mediation Server

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