On Monday 21 May 2007 11:09, Pierre-Emmanuel Le Roux wrote: > I think there is a problem with the HostEtherFilter module and multicast > address handling. > > An ethernet address is multicast if the bit 0 of the first byte is set to > '1'.
I believe indeed there is an error there, as the IANA states in <http://www.iana.org/assignments/ethernet-numbers>: ETHERNET MULTICAST ADDRESSES An Ethernet multicast address consists of the multicast bit, the 23-bit vendor component, and the 24-bit group identifier assigned by the vendor. For example, DEC is assigned the vendor component 08-00-2B, so multicast addresses assigned by DEC have the first 24-bits 09-00-2B (since the multicast bit is the low-order bit of the first byte, which is "the first bit on the wire"). Another list of Ethernet multicast addresses is maintained by Michael A. Patton and is accessible at: <URL:http://www.cavebear.com/CaveBear/ether-codes.html> <URL:ftp://ftp.cavebear.com/pub/Ethernet-codes> <URL:gopher://ftp.cavebear.com/00/pub/Ethernet-codes> Ethernet Type Address Field Usage Multicast Addresses: 01-00-5E-00-00-00- 0800 Internet Multicast [RFC1112] ... All examples there do not work with the 0x80 mask. Although I find it very strange that no one else noticed this. Bart -- Bart Braem PATS research group Dept. of Mathematics and Computer Sciences University of Antwerp Campus Middelheim, G3.30 Middelheimlaan 1 B-2020 Antwerpen, Belgium Phone: +32 (0)3 265.32.91 Fax: +32 (0)3 265.37.77 Web: www.pats.ua.ac.be/bart.braem
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