Asterisk Adventure – The Prelude

I am going back pretty far into the past, but I want to tell the story here.

Work has been using the same phone system for about a million years. The main part of it is an old Siemens Analog PBX that used to be interfaced with a PRI and has since been converted by the Provider From Hell (PRF – a lot more on that later) to use an Adtran SIP>PRI Gateway to utilize a SIP trunk to varying success over a T1 line to the office.

The problems with this system are myriad.

• Unreliable call quality

• Regular crashes of the PBX requiring a hard reboot

• Intermittent Trunk to PSTN routing problems that result in fast busy when dialing

Trying to diagnose the issues are compounded by the fact that we are using ancient equipment with a million points of failure and the PRF is very hard to deal with in getting a straight answer about anything. I will concede that my users are also incredibly hard to deal with in that they seem to have unlimited free time in their complaining schedule, but there accurate notation of errors schedule is completely booked.

All this is a nightmare, and considering when this all started, I knew basically nothing about telecom and VoIP other than that carried voice over IP, hence the name, I was highly reticent to involve myself at all in the process.

It finally came to pass that the difficult users and the PFH built up enough hatred towards one another that they needed to divorce, and hey, I handle IT right, it should totally be your job to fix all this.

Now it was the time to embark on a project to hopefully achieve all of the stated goals:

• Provide relatively reliable phone service

• Save a bunch of money

• Be able to handle everything but the data link and trunk in house.

If you are still reading this and don’t know what VoIP or a SIP trunk are, VoIP stands for Voice over Internet Protocol, which takes standard phone communication and directs a lot of it over the internet, rather than the PSTN (Public Switched Telephone Network) and in the process saves money in a lot of cases. Also since it works over IP, Techies like myself have an easier time working with it because we are already familiar with IP.

A SIP trunk is a service that takes SIP (Session Initiated Protocol) communications (the most popular way to transmit VoIP) and connects them to the PSTN if necessary so that Internet calls can become “real” calls and go over the phone network and ring your grandma’s old-school phone line.




Posted in Networking, VoIP.

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