非常实用的SIP穿越NAT解决方案，初学者也能看懂的文章-very practical SIP NAT traversal solution, beginners can also read the article

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