Asterisk Large Scale Deployment Examples / Reports

I’m working on a Student Project concerning a network for a Hospital Complex.
The Hospital has 22000 employees, multiple (about 10) buildings across about a square kilometer.
There are going to be about 700 fixed IP posts, 200 DECT IP phones and between 50-280 analog posts.
At first we looked at the Avaya IP Office solution, but they charge high prices for hardware and licensing. An Asterisk solution would be less than 1/3 of the cost.

I talked to 2 of the project supervisors; they would give Asterisk a chance if I can give convincing arguments.
I am now looking for reference projects where an enterprise of this scale successfully set up and runs Asterisk.
I couldn’t find anything on the Asterisk homepage (maybe that would be a valuable addon to the page).

I run asterisk in the enterprise. (multiple building, multiple cities, & countries )

Here is what asterisk does well

  1. No crazy license fees (Recommend you buy g729 but @10 / channel its not costly)
  2. No limits just what you skills are. and your time.
  3. chan sip is rock solid
  4. asterisk integrates with a lot of stuff if you can write dialplan for it or agi.

Here is what asterisk does not so well.

  1. astdb doesn’t cluster, doesn’t scale up to clusters (active note + standby is fine but not active / active)
  2. Realtime asterisk doesn’t have front end config tools available. So then you go back to writing dialplan by hand in sql. Sqloy is okay but it sucks compared to other ways.
  3. phone provisioning can be brutal if you have no tolls for it. suggest you stay with very few models of phones and vendors such as Polycom.

Were most asterisk implementations have the most issues around the items that become maintenance costly. Daily costs for things like add moves changes are a concern in asterisk environments. As well reporting in asterisk is based on cdr data. If you have queues you will want to have a look at Queuemetrics for queue reporting. But honestly if only 3 times the cost avaya is a deal. I would expect everyone else to be 10 to 15 times the cost.