Obviously SIP is considerably better than H.323 and complies with the understanding of IP-telephony as a global mass IP-service, and it should be implicitly considered right this way. And as SIP is able to serve not only telephony but also any communications at all in the real time over the IP-protocol; obviously it should become a base for other IP-services not yet existing but will appear in the future, as well.
GMT es un operador de telefonia fija y movil virtual, con licencia para operar, tenemos rutas directas a europa y los principales paises de latino/america, estamos interesados en negocios bilaterales, con carriers de todo el mundo.