[ih] Installed base momentum (was Re: Design choices in SMTP)

[John Day]

Okay, thanks.

There was an attempt by Michel Gien and Steve Bunch to convince Joy to do something sane, but he wasn’t persuaded.
Yea, Unix didn’t support IPC and it had to be added. You could get NCP in the kernel, but not TCP in the early PDP-11s.

It really was unfortunate that sockets was adopted. Another opportunity missed.

Take care,
John


> On Feb 13, 2023, at 16:07, Craig Partridge <craig at tereschau.net> wrote:
> 
> Hi John:
> 
> Oh no, far more complicated than that.  As I recall (and my memory on this is probably imperfect as I was young and learning and some things went over my head):
> 
> Bill rewrote the BBN TCP to make it more efficient.  The BBN TCP used a function table that was indexed by connection state and TCP segment type (so you looked up the connection using the TCP/IP header, then grabbed the segment type, and called the indexed function along with the PCB and inbound segment).  It made for tight and simple routines... but, as I recall, the VAX (the primary platform at the time) made function calls expensive, so Bill wanted a minimal number of function calls and produced long routines as a result (cf. tcp_input in 4.2BSD).
> Bill (or someone) at Berkeley came up with the idea of sockets and the socket/bind/listen/connect API as they did not like /dev/tcp and ioctls (which BBN TCP used and which Dennis Ritchie independently came up with for System V UNIX).  While ioctls and /dev/tcp may have fit the existing UNIX philosophy, having taught thousands of students in the 1990s sockets and had a few then encounter System V and say "ugh", Berkeley was probably right on this one.
> Various innards of the BSD implementation were cribbed from the BBN TCP.  A good example is mbufs -- invented by Rob Gurwitz when he ported an early TCP (Jack Haverty's???) to BSD.  I seem to recall seeing a memo from Rob c. 1988 saying mbufs were a hack to solve an immediate porting problem and that he was surprised a better solution had not materialized.
> The 4.1BSD BBN TCP was more stable than the 4.1c BSD (first socket) TCP and there was a period in which DARPA was (unhappily) funding both TCPs because many sites asked to have the BBN TCP so they could have reliable Internet connectivity.  This lasted a certain number of years into 4.2BSD, but eventually went Berkeley's way.
> Craig
> 
> On Mon, Feb 13, 2023 at 1:35 PM John Day <jeanjour at comcast.net <mailto:jeanjour at comcast.net>> wrote:
> So Berkeley’s position was that they were to port the BBN implementation bugs and all?
> 
> And BBN is to blame for sockets?  What a lost opportunity.
> 
> The first Unix on the Net in 1975 didn’t do that.  It used file_io.
> 
> 
> > On Feb 13, 2023, at 15:28, Craig Partridge via Internet-history <internet-history at elists.isoc.org <mailto:internet-history at elists.isoc.org>> wrote:
> > 
> > HI Scott:
> > 
> > Small nit.
> > 
> > DARPA funded Berkeley to port the BBN Unix to BSD -- and Bill Joy chose to
> > reimplement and develop sockets.  Much behind the scenes fighting ensued (I
> > was hired into that fight in 1983 when BBN concluded it needed to train
> > someone to understand the BSD implementation).  Led to various odd
> > conversations years later -- I remember Van Jacobson justifying a TCP bug
> > in the BSD implementation by saying it had been in the BBN implementation
> > that Bill used as a reference -- c. 1989, long after BBN BSD TCP was gone.
> > 
> > Craig
> > 
> > On Mon, Feb 13, 2023 at 12:50 PM Scott Bradner via Internet-history <
> > internet-history at elists.isoc.org <mailto:internet-history at elists.isoc.org>> wrote:
> > 
> >> for what its worth - here is my take on some of the reasons that the
> >> Internet (and specifically
> >> TCP/IP) took over the world
> >> 
> >> Forks: Decisions that got us the Internet we have
> >> https://www.sobco.com/presentations/2020-06-25-forks.pdf <https://www.sobco.com/presentations/2020-06-25-forks.pdf>
> >> 
> >> Scott
> >> (I, along with Scott Shackelford, have a book on the subject that should
> >> be published at some
> >> point - the text is done & now in publisher wait)
> >> --
> >> Internet-history mailing list
> >> Internet-history at elists.isoc.org <mailto:Internet-history at elists.isoc.org>
> >> https://elists.isoc.org/mailman/listinfo/internet-history <https://elists.isoc.org/mailman/listinfo/internet-history>
> >> 
> > 
> > 
> > -- 
> > *****
> > Craig Partridge's email account for professional society activities and
> > mailing lists.
> > -- 
> > Internet-history mailing list
> > Internet-history at elists.isoc.org <mailto:Internet-history at elists.isoc.org>
> > https://elists.isoc.org/mailman/listinfo/internet-history <https://elists.isoc.org/mailman/listinfo/internet-history>
> 
> 
> 
> -- 
> *****
> Craig Partridge's email account for professional society activities and mailing lists.