开源防火墙，非常简单，功能全面，时候初学者尤其是刚学防火墙的同学-Open source firewall is very simple, fully functional, especially for beginners just learning when students firewall

jVoIP is a simple SIP Phone based on NIST Sip Communicator. The phone won t be a fully functional SIP Client: it won t support REGISTER request it will be design for LAN voice communication This phone won t function behind NAT or