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Sorry Guys, My Google Fu is failing

Sorry Guys, My Google Fu is failing

Sorry Guys, My Google Fu is failing

Sorry Guys, My Google Fu is failing me on this one. I know something like this exists and maybe one of you has it squirreled away or knows where to find it.

TLDR at the bottom.

I have a customer that currently has 4 active QSIG Trunks between a SX-2K and Cisco Call Manager across 2 locations. They also have a total of 8 PRI Trunks (4 at each location). All of this is going to be transitioned over to the Cisco. The 8 PRI's will be transitioned to SIP early on and the Mitel Handsets (about 3000) will be moved over a timeframe of about 18 months.

Initially, when the SIP trunks are installed, the traffic to the Mitel over the QSIG trunks will increase significantly and will fall off gradually as the Mitel handsets are transitioned.

There are 2 areas in this where traffic capacity is a concern to the customer.
  1. How Many SIP Trunks will be required to replace the existing PRI's for both sites

    • Site 1 currently has a max simultaneous usage lower than 40 channels
    • Site 2 Currently has a max simultaneous usage lower than 30 channels

    • My thinking on the SIP is to design it for 70 channels with extra capacity via bursting

  2. How Many QSIG Channels will be be required. This one is of the most concern

    • If it is a one to one relationship we will need approx 70 more QSIG channels initially
    • Currently we are using about 23 of 96 channels and adding 70 will be 93 of 92
    • We have a 5th QSIG trunk tested and waiting to add capacity up to 115 making it 93 of 115

    • This is where the customer wants a written proposal outlining how the capacity will be sufficient

I know, or at least I am very confident, that I've seen a graph that represents the the number of channels needed in a given PRI based on estimated traffic. I am also sure that the graph is not linear. As such, adding a 5th Qsig trunk does not only add an extra 25% capacity, but actually significantly more than 25%. I'm guessing around 50%. If I need to document this, guess work will not be sufficient, thus I need that graph. Does anyone have one handy or know where I can find one?

RE: Sorry Guys, My Google Fu is failing

The Mitel SE Tool (Excel spreadsheet with a bunch of macros to calculate traffic load & hardware requirements) should be able to tell you what you need. I have a copy from around 2014, not sure if it contains info for the 2K in that version.

RE: Sorry Guys, My Google Fu is failing

Check your email that's listed in your profile.

RE: Sorry Guys, My Google Fu is failing

Thanks Lundah, that's even better than what I was asking for and I can make my own graph from the data.

A couple of stumbling blocks though, it's Excel 97-2003. I'm running O365 with 2023 version. Enough has changed that I'm unsure if it would still work after conversion. Also, and this one I can probably resolve after changing some of my settings, the Macro's won't enable.

Are you able to run it in it's original form and if so, can you assist me if need be?

I'm going to see if Mitel has this tool in an updated form and publicly available

RE: Sorry Guys, My Google Fu is failing

Nope, the system config tool is not going to be useful for my scenario and what I'm trying to figure out it treats all PRI trunks as one as far as Traffic is concerned as far as I can tell.

I did find an Erlang-B calculator online and I can use it to create my own graph.

Problem Solved

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