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[ih] XEROX/PUP and Commercialization (was Re: FYI - Gordon Crovitz/WSJ on "Who Really Invented the Internet?")

O, right!  I had forgotten about the colored ball protocols.  Good 
grief they were a mess!

There was a rather well-known Tymnet paper in the mid-to-late 70s 
about them.  When I read the paper back then it really gave the 
impression of a group stumbling into how a network works, rather than 
thinking it through first. They didn't see the flow control problems 
coming.  It was all "wait until it happens and retrofit a fix."

As to X.25, it suffered from what all ITU efforts suffer from: 
shooting for a market window 15 minutes in the future.  Well that and 
trying emulate what they knew. There was no way anyone was going to 
handle even modest bandwidth with that protocol.  Yet the Europeans 
kept insisting all through the 80s that it was the answer to 

The earlier comment on the cost of accounting.  That had nothing to 
do with the technology.  One could have charged a flat fee for X.25 
just as easily as for the Internet.  It was more the perception of 
whether the resource was plentiful or scarce.  Europe had always had 
the experience that everything was scarce (and they were a bunch of 
greedy bastards!)  ;-)

The fear that the PTTs in Europe would require attaching only their 
equipment was real and other onerous constraints.  It was fighting 
that that caused Pouzin to be basically black listed.  In the US, we 
had Carterphone, which would have prevented that.

At 7:39 -0400 2012/07/30, Vint Cerf wrote:
>TYMNET engineering eventually ended up reporting to me when I was
>still at MCI/Worldcom.
>In 2003, if memory serves, one of my engineers, Scott Huddle, planned
>and oversaw the shutdown of the MCI TYMNET x.25 service. Considering
>that x.25 was standardized around 1976, that's a pretty good run. Of
>course, TYMNET was started earlier than that, around 1968, using the
>"colored ball" protocols and given a patina of x.25 when that became
>the preferred interface for packet networking. British Telecom
>continued to operated its portion of the X.25 TYMNET until 2004 (see
>Wikipedia for TYMNET).
>On Mon, Jul 30, 2012 at 2:25 AM, Marty Lyons <marty at martylyons.com> wrote:
>>  On Jul 29, 2012, at 8:14 PM, Dave Crocker wrote:
>>>  I don't believe for one minute that X.25/X.75 were capable of the 
>>>kind of usage TCP/IP has experienced.  The complexity and 
>>>limitations they imposed seem to me to require massively more 
>>>expensive and massively less flexible, robust, etc., etc., 
>>  In the U.S. some of the X.25 universe of companies included 
>>Telenet (last owner: Sprint), Uninet (part of Sprint circa 1986), 
>>and Tymnet (last owner: MCI/Verizon).  There were some other 
>>networks as well, but Telenet and Tymnet continued operating the 
>>longest until being replaced by the IP backbones of their parent 
>>companies.  I'm not sure of the final dates but I seem to recall 
>>sometime around 1997 the last X.25 backbones were withdrawn for new 
>>  One of the principle reasons X.25 failed was the utter complexity 
>>of getting reliable and fairly priced billing contracts.  Back in 
>>1982 the lab I worked at ran both a Telenet and Uninet node, and 
>>the bills were very expensive and difficult to verify for 
>>correctness.  Around 1985, I got the same lab connected to BITNET 
>>on a 9600bps leased line, and the accounting was simple -- one flat 
>>rate per month.  BITNET took off in terms of universities joining 
>>because all you needed was two CSUs, a friendly partner site to 
>>connect to, and a little bit of money for a circuit (this was still 
>>in the era of requiring government sponsorship for ARPA 
>>connectivity, so this was the easiest way to get a dedicated campus 
>>connection). Almost every BITNET site ended up with a fully loaded 
>>circuit very quickly, particularly when the undergrads discovered 
>>online chatting (see stories elsewhere of how BITNET RELAY almost 
>>shut down the network due to load).
>  >
>>  In 1993, building the network at America Online I found that our 
>>X.25 providers were sending us massive bills and we still couldn't 
>>get a handle on the finances (ten years after my university days 
>>and apparently nothing had changed).  We moved as fast as possible 
>>to trunk all the traffic on IP backhaul.
>>  So one argument in why the Internet (in all its component parts) 
>>has succeeded was the simplicity of bit accounting -- get a leased 
>>line, and pay one price for the connection per month, independent 
>>of loading of the circuit.  Buying channels or a full T-span has 
>>always made much more sense than paying a X.25 carrier to account 
>>for your packets, route them correctly, and manage load balancing 
>>in their cloud -- which never seemed to be handled well, since the 
>>routing tables had to be updated by hand and pushed to the control 
>>  TCP/IP moved us from a world of "the phone company" where the 
>>model was charge-by-packet and let someone else do network control, 
>>to simple finances and control of our own network management. There 
>>was just no way financially or administratively X.25 stood a chance 
>>once NSF dropped the AUP, and people could buy a Cisco router, call 
>>UUnet/CIX member and get connected directly.  X.25 was the 
>>mainframe of the networking world (centralized control), TCP/IP was 
>>the IBM PC (decentralized).
>>  Around 1995, I had conversations with several (different) IP 
>>backbone providers which were trying to figure out how to sell 
>>connections with bit rate billing. Thankfully that never happened. 
>>I got the impression that some were close to floating it as a 
>>product though.
>>  Having run networks of every one of those "other" protocols (SNA, 
>>DECnet, XNS, SPX/IPX), it was a happier time when they all finally 
>>seemed to go away.  Of all of the alternatives, XNS was probably 
>>the most interesting and if Xerox had licensed it correctly, it may 
>>have had wider use.  And SNA continues to live on in private 
>>environments -- some quite substantial.
>>  Side story on deployment in interesting places: I converted all of 
>>South Pole Station, Antarctica to TCP/IP in November 1991. 
>>Previously the station used a mix of various protocols.  The Suns 
>>were ready out of box, but once the Vaxen has TGV MultiNet 
>>installed, the pole was free from gulag DECnet and we enabled lots 
>>more science to happen by installing freeware IP clients on PCs and 
>>  Marty