Ernest G. Wilson II's ARS (Automatic Route Selection) guide for Avaya ARS

Many Avaya administrators and Avaya systems claim to use ARS (Automatic Route Selection).
In truth few organizations actually tap into the huge cost saving capabilities that was a key reason you bought your Avaya system.

Q. What is Avaya ARS (Automatic Route Selection)?
A. Simply put: Having your Avaya gear pick the best possible line each time your users make a call.
    A more detailed answer would say:
        - picking a line that is most cost effective in terms of long distance toll charges
        - picking a line that uses the fewest network resources to conserve bandwidth and limit complexity and possible failures
        - automatically selecting the best possible line / network path seamlessly behind the scenes for each user even in changing conditions

        ARS is one of the big selling features of an Avaya enterprise class phone system.
Companies can have a large phone system connected to multiple geographic locations with varying call capability at each site.
In my experience, I have designed and implemented a system in the state of Delaware that spans three (3) counties.
Having a phone system that spans three (3) counties means no longer paying toll charges to Verizon for cross county calling!
For example a worker in New Castle County can call his home in Kent County without using the Telco to cross the county line.
Our phone system would see that the user is in New Castle but correctly select a Kent County phone line to call out locally.
This miracle of selecting a local phone line to avoid a toll charge is called ARS (Automatic Route Selection).
The "Automatic" part is seamless to the user, but required some careful planning and programming ahead of time by the engineer (me)!

        Planning and implementing a correct and fully functional ARS system ultimately requires many very specific details about each site.
You will need to know each of your site's specific NXX (local calling prefix capabilities), create trunk groups, build route patterns and ultimately
ARS analysis tables.  In the course of doing so, you will need to become familiar with some very specific Avaya ARS commands.  Before we get
into the nitty-gritty details, we need to step back and define our goals for ARS.  ARS has even deeper implications than saving you some money.
You must be cognizant of the fact that even 911 calls can and will be affected by ARS.  You wouldn't want an ambulance or fire truck sent to a
location simply because that is where the 911 operator determined that is where a call originated from!

        Surprisingly little information could be found on the Internet at the time of writing this document that could be used as a "grand plan"
or even as a design reference for building a complete ARS system.  This caused me to write a set of "rules" for ARS as building blocks.
Ultimately I created a set of rules that I call the "Golden Rules of ARS" - Any system that uses ARS should always obey the "Golden Rules"
Each time a user picks up the phone and dials "9" for an outside line, the system must follow these two (2) simple rules.

Ernest G. Wilson II's "GOLDEN RULES of ARS" for Avaya - Invoked automatically each time a users dials “9” to get an outside line

1. Calls should take the most desirable path available (no matter what the user dials after dialing 9)
       - Reduce long distance usage and Telco facility use
       - Use 5 digit method if viable
       - Use correct trunks based on NXX (regardless of origin)
       - Prefer the closest trunk group to the user first (if multiple trunks qualify – Use Site Specific ARS)
2. Overflow trunks in a logical succession
       - Use cost and distance to determine Route Patterns
       - Continue overflow until all trunks are utilized

        It sounds simple enough, just two (2) little rules to follow and your system will start saving you money instantly.
In practice however, very few systems in the world actually obey these two little rules.
And it is no wonder why, currently no dynamic ARS routing protocol exists and and admin must manually build and maintain tables.
Even for the state of Delaware having only three (3) counties, there is more than 450 possible NXXs currently in use.
Just figuring out which numbers can are local to each county and building and testing an "all" table is a multi-hour job.
Add in long distance, special numbers and class of service security restrictions like 411 and required 911 ability and it is a week long job.
Additionally, long term planning, documentation, testing and training easily adds another week of labor to an ARS project of only three (3) counties.

        I am very satisfied (and proud) with my current ARS configuration for the most part.  It has been a steep learning curve but very rewarding.
Our system correctly picks the desired outbound phone line for each call as needed and is saving thousands of dollars each month.  Our Avaya system
easily makes several million out bound calls each year currently and that number is growing as we add more staff and more sites.
As such, I want to share some of the information I put together when designing our ARS system.  This most basic information was earned the hard
way by me over time as I did not have the luxury of this blue print or even my golden rules at the onset.

Without further ado, here is my:
Ernest G. Wilson II's Avaya ARS Strategy Guide in MS PowerPoint format.
Please use at your own risk!