SIP is probably one a of the most important protocols for Internet, it has the faculty to make calls from Internet, mutually with TCP/IP and HTTP, they become to Internet in the architecture which people enjoy daily. Thinking to future what better idea that SIP would be a standard for VoIP signaling over Internet. The VoIP providers actually are systems which are not open to each others and over Internet. This is the reason for not seeing SPIT (Spam Over Internet Telephony) as VoIP garbage like a big problem actually, from a reductionist perspective the SPIT problem is planted to know who will communicate to who, the problem is affronted as an identity trouble. If the sender identity is known then an authorization can or cannot be accepted.