Ekiga
From Guardian Project Wiki
Ekiga is a free software SIP client. The developers also support a free SIP service. Can support ZRTP but does not support encrypted SIP.
Network scan results
lee@ikaruga:~$ nmap ekiga.net Starting Nmap 5.21 ( http://nmap.org ) at 2012-03-09 14:51 PST Nmap scan report for ekiga.net (86.64.162.35) Host is up (0.16s latency). Not shown: 989 closed ports PORT STATE SERVICE 22/tcp open ssh 25/tcp open smtp 80/tcp open http 113/tcp open auth 143/tcp open imap 389/tcp open ldap 443/tcp open https 465/tcp open smtps 993/tcp open imaps 1002/tcp open windows-icfw 6666/tcp open irc lee@ikaruga:~$ dig SRV _sips._tcp.ekiga.net ; <<>> DiG 9.7.3 <<>> SRV _sips._tcp.ekiga.net ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 18651 ;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0 ;; QUESTION SECTION: ;_sips._tcp.ekiga.net. IN SRV ;; AUTHORITY SECTION: ekiga.net. 85743 IN SOA dns.ovh.net. tech.ovh.net. 2011063001 86400 3600 3600000 86400