From: Paul Ruizendaal <email@example.com>
To: Dan Cross <firstname.lastname@example.org>, Warner Losh <email@example.com>
Cc: "firstname.lastname@example.org" <email@example.com>
Subject: [TUHS] Re: when did v8 or later get networking?
Date: Sat, 12 Aug 2023 18:12:32 +0200 [thread overview]
Message-ID: <3E932445-F917-4E3E-A13A-A8E5557280F3@planet.nl> (raw)
Universal Receiver Protocol, the protocol that Sandy Fraser invented for Datakit. The best description of it (imho) is the patent:
At first the patent is very focused on hardware implementation, but towards the end it gives the algorithms in pseudo-code.
Sandy Fraser wrote a 1993 retrospective paper “Early Experiments with Asynchronous Time Division Networks”. This paper includes a short summary of the origins of the universal receiver protocol, and how it evolved through 3 main steps. Unfortunately behind a paywall.
The implementation for 8th edition (some 750 lines) is here:
I think early Plan9 had an implementation of URP as well.
> On 12 Aug 2023, at 17:24, Dan Cross <firstname.lastname@example.org> wrote:
> On Sat, Aug 12, 2023 at 11:20 AM Warner Losh <email@example.com> wrote:
>> On Sat, Aug 12, 2023, 4:29 AM Paul Ruizendaal <firstname.lastname@example.org> wrote:
>>>> URP is smaller, but if I remember well it does not handle out-of-order packets or packet duplicates (both of which do not occur in a (virtual) line switched context).
>>> Upon reflection, duplicates of course can occur when an ACK is lost.
>> What's URP? Sounds a little like UDP, is it a typo or something else?
> I thought that might be a typo for UDP, but that doesn't have ACKs.
next prev parent reply other threads:[~2023-08-12 16:13 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-08-11 9:05 Paul Ruizendaal
2023-08-12 5:08 ` Warner Losh
2023-08-12 5:41 ` George Michaelson
2023-08-12 9:06 ` Paul Ruizendaal
2023-08-12 10:29 ` Paul Ruizendaal
2023-08-12 15:20 ` Warner Losh
2023-08-12 15:24 ` Dan Cross
2023-08-12 16:12 ` Paul Ruizendaal [this message]
-- strict thread matches above, loose matches on Subject: below --
2023-08-12 15:05 Noel Chiappa
2023-08-12 18:00 ` Paul Ruizendaal
2023-08-10 1:09 [TUHS] " Larry McVoy
2023-08-10 2:38 ` [TUHS] " segaloco via TUHS
2023-08-10 2:45 ` Warner Losh
2023-08-10 3:17 ` segaloco via TUHS
2023-08-10 3:18 ` Rob Pike
2023-08-10 5:44 ` John Cowan
2023-08-10 12:41 ` Douglas McIlroy
2023-08-10 14:00 ` Jonathan Gray
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).