From: Larry McVoy
TCP/IP was the first wide spread networking stack that
you could get
from a pile of different vendors, Sun, Dec, SGI, IBM's AIX, every kernel
supported it.
Well, not quite - X.25 was also available on just about everything. TCP/IP's
big advantage over X.25 was that it worked well with LAN's, whereas X.25 was
pretty specific to WAN's.
Although the wide range of TCP/IP implementations available, as well as the
multi-vendor support, and its not being tied to any one vendor, was a big
help. (Remember, I said the "_principle_ reason for TCP/IP's success"
[emphasis added] was the size of the community - other factors, such as these,
did play a role.)
The wide range of implementations was in part a result of DARPA's early
switch-over - every machine out there that was connected to the early Internet
(in the 80s) had to get a TCP/IP, and DARPA paid for a lot of them (e.g. the
BBN one for VAX Unix that Berkeley took on). The TOPS-20 one came from that
source, a whole bunch of others (many now extinct, but...). MIT did one for
MS-DOS as soon as the IBM PC came out (1981), and that spun off to a business
(FTP Software) that was quite successful for a while (Windows 95 was, IIRC,
the first uSloth product with TCP/IP built in). Etc, etc.
Noel