Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!think.com!spool.mu.edu!agate!ucbvax!bloom-beacon!eru!hagbard!sunic!ugle.unit.no!nuug!ifi!enag From: enag@ifi.uio.no (Erik Naggum) Newsgroups: comp.protocols.tcp-ip Subject: Re: Unused portion of first octet? Message-ID: Date: 21 May 91 00:06:44 GMT Article-I.D.: gyda.ENAG.91May21020637 References: <1991May20.160942.24296@homecare.COM> <1991May20.165505.14235@salt.acc.com> Sender: enag@ifi.uio.no (Erik Naggum) Organization: Naggum Software, Oslo, Norway Lines: 25 In-Reply-To: art@opal.acc.com's message of 20 May 91 16: 55:05 GMT Art Berggreen writes: | | Its not actually the first octet, bit the first bits, as follows: | | 0XXXXXXX.XXXXXXXX.XXXXXXXX.XXXXXXXX Class A | 10XXXXXX.XXXXXXXX.XXXXXXXX.XXXXXXXX Class B | 110XXXXX.XXXXXXXX.XXXXXXXX.XXXXXXXX Class C | 1110XXXX.XXXXXXXX.XXXXXXXX.XXXXXXXX Class D (Multicast) | 1111XXXX.XXXXXXXX.XXXXXXXX.XXXXXXXX Reserved I think it's easier if you present it with network and host numbers: 0nnnnnnn.hhhhhhhh.hhhhhhhh.hhhhhhhh Class A 10nnnnnn.nnnnnnnn.hhhhhhhh.hhhhhhhh Class B 110nnnnn.nnnnnnnn.nnnnnnnn.hhhhhhhh Class C 1110mmmm.mmmmmmmm.mmmmmmmm.mmmmmmmm Class D (multicast) 1111xxxx.xxxxxxxx.xxxxxxxx.xxxxxxxx Reserved Of course, then there's subnetting... -- Erik Naggum Professional Programmer +47-2-836-863 Naggum Software Electronic Text 0118 OSLO, NORWAY Computer Communications