[builtinbuffalo]

This is true, but new competitors also haven't been around as long as Avaya. Before Asterisk and other software hit the market, there were four players - Avaya, Cisco, Mitel and Nortel. Now there are dozens of large players and hundreds of medium sized ones. These companies are gaining market share in the enterprise - just checkout the exhibitor list for enterprise connect 17.

[jessaustin]

In addition, there are random local dudes who can set up an office Asterisk system based on commodity hardware for like $2000, and whom you can pay another $200 every couple of years when something needs to be changed. An Avaya system can't get close to that.

[tsomctl]

I've torn out several Asterisk systems because that random local dude grew tired of dealing with Asterisk. Toshiba, which is a competitor of Avaya, does get close to that.