Allstar/app_rpt (also called AllStarLink) is a complete repeater (or simplex node) controller with Voice Over internet Protocol (VoIP) linking and more features that most repeater controllers. Asterisk/app_rpt can run on many single board computers including the Raspberry Pi. Multiple repeaters (nodes) may be interfaced at one site while only running one instance of Asterisk/app_rpt on one computer. Any node can connect with any other node. Any number of nodes can connect to a node (subject to bandwidth limitations) forming a hub.
AllStarLink Main Wiki Page
https://wiki.allstarlink.org/wiki/Main_Page
ASL FAQ
https://wiki.allstarlink.org/wiki/ASL_FAQ
IAX Router Settings
https://www.voip-info.org/iax/
K5TRA AllstarLink Page
Has hardware and configuration info plus links to other related pages: http://k5tra.net/AllstarLink.html
Startech Audio CM108 FOB Conversion
http://www.repeater-builder.com/projects/fob/startech-fob.html
WA6ZFT CM108 Audio Fob Conversion (pdf)
http://www.repeater-builder.com/projects/fob/usbfob.pdf
N4TXI Blue Chinese Audio FOB Conversion
http://www.garydion.com/projects/usb_fob/
Baofeng BF-888S AllStar Node Conversion using Blue Chinese FOB
http://www.garydion.com/projects/Allstar_node_1/
Detailed BF-888S Conversion
http://crompton.com/hamradio/baofeng888/
Matthew Harrold Blue Chinese FOB Conversion
http://www.marrold.co.uk/2018/04/converting-cm108-usb-fob-for-amateur.html