Since the assigned numbers RFC doesn't get updated all that often, you
might want to consult the "Ethernet-codes" file. See attached blurb
from the file (my copy last updated 8-Apr-93).
This file contains collected information on the various codes used on
IEEE 802.3 and EtherNet. There are three "pages", type codes, vendor
codes, and the uses of multicast (including broadcast) addresses. I
wish to thank the contributors, some are listed below and there are
almost certainly others that I have missed. A complete up-to-date
copy of this file may always be obtained with anonymous FTP from
FTP.LCS.MIT.Edu with the name pub/map/EtherNet-codes. Since this
information is from collected wisdom, there are certainly omissions.
I welcome any further additions which can be sent to me at
Columbia University fuat @
703 Watson Labs 212-854-4804
612 W115th Street 212-662-6442 (Fax)
New York, NY 10025