This theory does not work,
however, for data networks.
When data is sent using smaller packets, it takes many more packets for the successful
transfer of large data files. This is not only inefficient; it can create a lot of overhead
within the network. ATM was a compromise between the two; providing smaller packets
for voice and video, eliminating the delays in packet transmission, while offering
large enough packets to support the transfer of larger data files.
TCP/IP development has continued as well. The Internet Engineering Task Force
(IETF) realized that the TCP protocol is not a good transport for real-time applications.
They set off to create a new peer protocol referred to as Stream Control Transport
Protocol (SCTP). This protocol was first used in support of SIGTRAN (SS7 transport
over IP) and has since expanded to other uses within the VoIP domains.
Many of the shortcomings of IP have been addressed, and service providers have
quickly learned the economies brought about by an IP infrastructure. Yet providing
highly reliable and secure telecommunications services over an IP network requires
some changes to the technology as well as the implementation of IP networks.
One of the key issues with VoIP is really an implementation problem. There is lacking
a set of implementation/interoperability standards for the deployment of a VoIP network.
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