Max. FXS/FXO ports: 48- Max. concurrent calls: 48- SIP/MGCP protocols- 500 routing and number manipulation rules- Fax over IP using T.38 & G.711 pass-through- Dual redundant Ethernet ports- Dual DC/AC power supplies available- PSTN failover- TLS/SRTP- Auto provisioning- Remote access via the Redstone Cloud – Management with the Redstone or third-party Remote Device- Management Systems TR-069, SNMP- Interoperability with popular SIP servers, such as Cisco CallManager/CUCM, Broadsoft, Microsoft Skype for BusinessLync, and Asterisk/Elastix- Class I lightning protection