From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, HTML_MESSAGE,MAILING_LIST_MULTI,NUMERIC_HTTP_ADDR autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 12407 invoked from network); 7 May 2022 19:21:00 -0000 Received: from minnie.tuhs.org (45.79.103.53) by inbox.vuxu.org with ESMTPUTF8; 7 May 2022 19:21:00 -0000 Received: by minnie.tuhs.org (Postfix, from userid 112) id A910C9D434; Sun, 8 May 2022 05:20:58 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id D1A529CEEF; Sun, 8 May 2022 05:18:51 +1000 (AEST) Authentication-Results: minnie.tuhs.org; dkim=pass (2048-bit key; unprotected) header.d=bsdimp-com.20210112.gappssmtp.com header.i=@bsdimp-com.20210112.gappssmtp.com header.b="k/HjgheV"; dkim-atps=neutral Received: by minnie.tuhs.org (Postfix, from userid 112) id 2ED4A9CEEF; Sun, 8 May 2022 05:15:02 +1000 (AEST) Received: from mail-vs1-f54.google.com (mail-vs1-f54.google.com [209.85.217.54]) by minnie.tuhs.org (Postfix) with ESMTPS id 1FEB19CEEE for ; Sun, 8 May 2022 05:15:01 +1000 (AEST) Received: by mail-vs1-f54.google.com with SMTP id a127so10292963vsa.3 for ; Sat, 07 May 2022 12:15:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bsdimp-com.20210112.gappssmtp.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=BoQ//fQhv7ffs3n/rTxY6MefW4gue9obEXzxC02R1vY=; b=k/HjgheVpiVB7Bde6zA659ev28597C+zv/lLqHsUgVFRQtfDw2NOaGcASCKnA00mJA 5zLyo0DSfeYPvzFmnSWBF8PaQdFpbak69doYhCLzYoplX9NngtF0Zykh+fRHFkQrswj5 6Wxd8n/HsNWu4yEEEpYoAigNnd+haxswe+mwXL4Optaw5yUdDfKP3L4s7+pQ2RK1nYZ0 FTOEmvNfUbcqyoEzUKfo7QNgtQST63yMyehDsBLzv8Fd9drNn1uiv5/P7JH2YZf0iJEk ITNj3GF39MRZsNuwohwaNh9Xs/fdqxu+yY2/NBqyx7Lnlv2JF9S8bNRrKCkIDH/MVqfK I37A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=BoQ//fQhv7ffs3n/rTxY6MefW4gue9obEXzxC02R1vY=; b=rQh56YYzGonLQRgah6zr5QpVJgONMwpxpT1syj2KoPw84Bsga9MXczAUXIKQlLIlJz N8fP4vFcym2FuqYqcLZBKqTkIoELHlpKMGXqkfVbKPnTSittBNcUvOXPuvwjHP7FyCDf jPrJlC3Begs6ikrd05VIZiAjuS135k2MjAkzSC09KMaPAALx2oaRSI0cXV95VnvdSBic txEuobrvAt/mNOHlMZHSL1uZ/y8BXyIwGFa3FXQbmXGdZcAm1ACxH0SxmzxM8ZHnUdLh PF5UzqkRATQFyAF4CSl1UplQzYcnjlPIPIqnm8cDtTBgNyeLKhjDLwImkETvW8dGUIPY lbqw== X-Gm-Message-State: AOAM531Uln1YT0crcVERjjOqaOAvuzChNBEKbYOjiOl49XO2GedWi2uC UoTjP0mPmiWXNbPyqxGXI5Ir/T7Ok/NZVzwXBNkLxprGgLQ= X-Google-Smtp-Source: ABdhPJyTnleYnylYLJeFSN9uOfEwtegvga9T/EE0gav+plCc8w20oFI14F2QhKB/ZHcm8AeOHz5+1XkKTVeeeFPB0GE= X-Received: by 2002:a67:f445:0:b0:32c:c32c:c7c1 with SMTP id r5-20020a67f445000000b0032cc32cc7c1mr5073616vsn.51.1651950900050; Sat, 07 May 2022 12:15:00 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Warner Losh Date: Sat, 7 May 2022 13:14:48 -0600 Message-ID: To: ron minnich Content-Type: multipart/alternative; boundary="000000000000958f8b05de70cacd" Subject: Re: [TUHS] conventions around zero padding in ip4 X-BeenThere: tuhs@minnie.tuhs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: The Unix Heritage Society mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: TUHS main list Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" --000000000000958f8b05de70cacd Content-Type: text/plain; charset="UTF-8" On Sat, May 7, 2022 at 10:23 AM ron minnich wrote: > IP4 padding came up recently: the ip command interprets 10.2 as > 10.2.0.0, whereas most things (golang libraries, ping, ...) interpret > it as 10.0.0.2. The latter interpretation accords with what I learned > 40y ago. > 10.2 is ambiguous. In a network context, it means, typically, 10.2.0.0/16 (though your mileage may vary). In a host context, it means 10.0.0.2. It's this confusion that has lead to many efforts to outright kill this notation. > But, I find myself wondering: where was the first use of the IP4 zero > padding convention? > I know that it was around in the late 80s on TOPS-20 TCP/IP at Stanford, and in 4.2BSD (4.1c?). It may have also been in use at MIT. It's usage pre-dates my 1984 joining of the internet... Warner --000000000000958f8b05de70cacd Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable


=
On Sat, May 7, 2022 at 10:23 AM ron m= innich <rminnich@gmail.com>= wrote:
IP4 padding came up recently: the ip command interprets 10.2 as
10.2.0.0, whereas most things (golang libraries, ping, ...) interpret
it as 10.0.0.2. The latter interpretation accords with what I learned
40y ago.

10.2 is ambiguous. In a networ= k context, it means, typically, 10.2.0.0/16<= /a> (though your mileage may vary).
=
to outright kill this notation.
=C2=A0
But, I find myself wondering: where was the first use of the IP4 zero
padding convention?

I know that it was = around in the late 80s on TOPS-20 TCP/IP at Stanford, and in 4.2BSD (4.1c?)= . It may have also been in use at MIT. It's usage pre-dates my 1984 joi= ning of the internet...

Warner
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