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.
TELEflash is a registred Carrier in Germany with his own Portingcode, own Hardware and with dedicated Peeringconnections to other german Carriers. We also offer MVNO-Services with german SIM-Cards.