chan-sccp VS freeswitch

https://github.com/chan-sccp/chan-sccp should get you started. Follow the docs and their wiki also some good info. You will get base config files and what not to prep your tftp server. Just be forewarned its not a trivial task to get everything setup, I have a dedictaed voice vlan with special entries for DHCP options for tftp and ntp. Also be warned that the sccp phones are basically not secure, if all that doesn't scare you cool, so long as they are just on your local LAN and asterisk is secured properly it really doesn't matter. Also check out this here if your interested in running newer SIP cisco phones as well and want to keep all the UCM features.

I've got them running SCCP firmware, connected to FreePBX with chan_sccp and managed with SCCP Manager.

I will soon, but if you want something right now their guide is pretty good: https://github.com/chan-sccp/chan-sccp/wiki/FreePBX_Installation

Hopefully an update to allow speed changes will land... https://github.com/signalwire/freeswitch/pull/244

Some clarification on what you mean would be great.

When I look at their organization on Github I see quite a few active projects e.g. "Sharq" - SHARQ Server is an flexible, rate limited queuing system based on the SHARQ Core library and Redis. (https://github.com/plivo/sharq-server) as well as client packages in quite a few languages.

Beyond that the documentation you referenced clearly points out that FreeSwitch (https://github.com/signalwire/freeswitch) is the telephony engine (https://web.archive.org/web/20130314113846/http://docs.plivo...) and the install script from the docs shows that their roots are in Pilvo being a Python web app (https://github.com/plivo/plivoframework/blob/master/scripts/...). I also see a few Django applications in their repositories as well.

Thus, they open sourced their software. Are they open sourcing all of their software? Likely not. It could be that they open sourced much of their code and then got no contributions.

If they weren't receiving any contributions in alignment with their development, there would be no value for them to continue to have that distraction from running their business. It could also be that they didn't have the resources to _maintain_ external facing repositories, issues, and the communities around them.

Providing a more clear explanation of your expectations would help get you the best answer.

FreeSwitch is a telecom stack similar to Asterisk. See here: freeswitch. It would be to support VoIP on the UDMP.