Grandstream Networks DP752. Maximum range: 15748" (400 m), Supported network protocols: SIP RFC3261, TCP/IP/UDP, RTP/RTCP, HTTP/HTTPS, ARP/RARP, ICMP, DNS (A, SRV, NAPTR), DHCP, PPPoE,..., Security algorithms: 256-bit AES, HTTPS, MD5, SRTP, SSL/TLS...