Least Cost Routing

The Environment

A single Lync Deployment with two sites (with PSTN connectivity at each). One in Melbourne (Australia), the Other in Auckland (New Zealand). 

The Goal
When users homed to Melbourne call New Zealand numbers breakout to PSTN must be at the New Zealand gateway (not the Melbourne gateway – avoid international toll). And the other way around as well. Users homed to Auckland should breakout to PSTN at the Melbourne gateway when calling Australia numbers.

Currently I have a separate gateway at each site and a set of separate Voice Policies, Routes and PSTN Usage Records.

Voice Policy
Melbourne Users – All feature Enabled
Auckland User Policy
PSTN Usage
Melbourne PSTN Usage
LXL Bridge
Melbourne ISDN Gateway
LXL Bridge
We will configure Melbourne as an example
Start with the Route by adding an Exception. In New Zealand the E.164 format starts with +64 so we will exclude this from the Melbourne Route as below.

 NOTE The Digits are processed from the top down so if the * rule is on the top the rules below are ignored. Be sure to get the order correct.

Scrolling down on the Same Route we will ensure that only the Melbourne Gateway has been selected.

So far what we have done is prevent numbers starting with +64 (NZ) from being dialled via the Melbourne Gateway. Now on to allow these numbers over the Auckland Gateway.
From the Auckland Route add the PSTN Usage for the Melbourne users as below.

The result.
When Users homed to Melbourne call New Zealand Numbers (starting with +64) the Route to the Melbourne gateway will not allow the digit pattern. Searching through additional routes the digit pattern will then be matched to an allowed  string on the Auckland Gateway. Once the PSTN usage for this Route is confirmed the call will proceed.

All that remains is to replicate this in the opposite direction as well.

About Paul B

My name is Paul Bloem and I am employed at Lexel Systems in New Zealand as a Principal Consultant for Unified Communications. I have been working on enterprise voice solutions for over 20 years. My first 10 years were spent working for a Telco in South Africa (Telcom SA). This is where all the groundwork happened as I was exposed to just about every aspect of telecommunication you could imagine. I develop an interest in PBX technologies and eventually became the go-to guy. Next, I had a 10 year run at Siemens South Africa, most of my time there was as a Technical Trainer. During this time VoIP hit the world stage, I had the privilege of introducing VoIP both as H.323 and later SIP across the Siemens HiPath 4000 solution stack. In 2008 I immigrated to New Zealand with my newly attained MCSE, I was ready to go where no PBX Techie had gone before. I was employed to explore OCS 2007 and that was pretty much the beginning of the end for me. I have been working on OCS and Lync ever since. My current role focuses exclusively on Lync and associated technologies.. That includes pre-sales, consulting, architecture and design, training and support. I even get to play in the development space from time to time - focus on play ;-) I was nominated as a Microsoft VTSP for Lync early in 2013 and also awarded Microsoft's MVP award for Lync in 2014.
This entry was posted in LCR, Lync Call Routing, PSTN Breakout. Bookmark the permalink.

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