Understanding the network.pdf - Back to Home

from data communication. NCPs defined operational specifications and support for
specific TCPs or operated over their own proprietary TCP.
The problem with having a large variety of network transmission and
communication protocols is that they do not interoperate with one another from a
protocol basis, and some are even closed proprietary systems with limitedsupport
for proprietary computer systems. The OSI dream (created by telecommunications
and business worlds drifting in the sea of incompatible protocols) was to fulfill a
rather difficult task: to build data communication networks that work over a variety
of infrastructures and allow communication between a variety of system types.
Because the majority of NCPs were vendor-specific—that is, SNA, DECnet,
AppleTalk, Novell—TCP/IP was the only contender. TCP/IP was a
vendor-independent protocol suite developed in the government and research
world. This meant that it was a public domain network communication protocol suite,
free from royalty obligations. Until OSI came along, the standard networking
reference model for many was the Internet-RM (based on the TCP/IP protocol suite),
as shown in Figure 1.14.