Re: Libpcap :: 802.3 and Ethernet headers

[Andrew Brown <atatat () atatdot net>]

> > Am looking at the headers from 802.3 and Ethernet (RFC 894).  My
> > question is:  Off the wire how does one, libpcap for example,
> > differenciate between 802.3 and Ethernet encapsulation?
>
> By looking at the type/length field.  If it's <= 1500, it's 802.3; if it's
> > 1500, it's Ethernet.  (Actually, as I remember, according to the spec
> there's a small set of values that are neither valid for 802.3 nor for
> Ethernet, but I don't remember what the range is.)

that'd be 05dd to 05ff.  05dc is 1500, and 0600 is xerox ns idp.  :)

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