- IMS/SIP/MGCP protocols<br/>- Unequalled configurability of FXS and FXO ports<br/>- TLS/SRTP<br/>- L2TP/OpenVPN client<br/>- 500 routing and number-manipulation rules<br/>- Configurable SIP ports and IP-address whitelist<br/>- High-speed fax with maximum rate of 33 600 bps by T.38 or G.711 pass-through<br/>- Polarity-reversal/busy-tone detection<br/>- High availability & PSTN failover<br/>- Auto provisioning<br/>- Remote access via the Redstone Cloud*<br/>- Management with the Redstone or third-party Remote Device Management Systems (TR-069 SNMP)<br/>- Interoperability with popular SIP servers such as Cisco CallManager/CUCM Broadsoft Microsoft Skype for Business (Lync) and Asterisk/Elastix<br/>- Class I lightning protection
