As I have about 40 analog extensions, with existing infrastructure (analog phones and existing cable network) I am searching for appropriate solutions like FXS gateways or analog card. If possible I would like to buy used ones as my budget is limited. Furthermore It would be nice if it has RJ21 (telco 50 pin connector) connectors.
I looked around and found a Cisco VG248 but further research resulted that it only supports sccp and on the forum I have read more mixed feedback than good ones about that.
Can you recommend any gateways or suggest any companies?