[ih] Why did TCP win? [Re: Internet-history Digest, Vol 63, Issue 3

[Dave Crocker]

On 2/2/2025 3:16 PM, Brian E Carpenter via Internet-history wrote:
> I've always answered that with: Because it worked, had a full suite
> of applications, and it was free on Unix, and modestly priced on
> most other operating systems.

/Specs/ and reference software were both free.  Big advantage over OSI. 
(I think the Unix version was nice, but Unix had such a tiny market 
share at that point, I suspect it didn't sway the market choice as we 
might think.)

20 years of operational history.  Big advantage over OSI.

Telnet, FTP, email. In use over that entire time.

Quick updates and quick development of specs.  OSI, well, umm...


>
> After 1995 you could add "because of the Web".

TCP had clearly and definitively won by the latter 1980s, before the Web 
was created.

The Web added sex appeal, just in time for the mass-market knee of the 
growth curve to need it.


> (IBM watchers might add: it also worked over Token Ring,
> despite Ellen Hancock's best efforts.)

It ran over everything.  Someone should make a t-shirt about that.

And just as significantly, it ran /the same/ over everything. OSI didn't.


> That's over-simplified, but I think it's ~ true. A more subtle
> point is that all the OSI hype prepared the market for a single
> non-proprietary protocol suite, but TCP/IP was ready first. 

Indeed, OSI was wonderful strategic marketing, creating the pull for 
TCP. I forget the exact wording, but the comment was "OSI created the 
demand and TCP filled it".  Was that Marshall Rose or someone else?

I forget the exact percentage, but Europe was maybe 40% of our sales for 
TCP.

Latter 80s, we started looking to our customers for what they wanted, to 
do TCP-to-OSI transition, and they all came back saying their transition 
requirement was OSI-to-TCP...


d/

-- 
Dave Crocker

Brandenburg InternetWorking
bbiw.net
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