Set up your VOIP based SIP soft phone and know more about VOIP
VOIP (Voice over internet protocol) The trending technology of present and near future. I have spent months of efforts on voip , its a huge topic so to minimize your time and also to refresh my voip skills , I have decided to write this blog. Main Topics covered :- SIP (session initiation protocol) ASTERISK (open source voip server platform) SIP is a part of Application layer (fig1) in TCP/IP , its major function is to initiate/terminate a sip session and transfer it to TCP/UDP for transmission. In simple terms it holds the FROM and TO addresses in a post , the rest is carried using TCP/IP protocol. fig1 : SIP in TCP/IP The basic operation of SIP is an INVITE and ACK via proxy, once the opposite Sip phone B accepts the call, a media session is established. Its simple as shown in fig 2. The proxy might be a VOIP services provided by certain websites such as www.linphone.org , SIP2SIP.info etc or it...