Oops, overlooked this one. Any idea *how*? (I'm terribly busy these days so not much time to research it.)
Stephen Fisher wrote: > Let's disable it by default to avoid the overhead of checking every > packet. > > On Mon, Apr 16, 2007 at 05:53:19PM +0800, Jeff Morriss wrote: >> Hi list, >> >> What do you think--how should we go about this? >> >> -J >> >> Glattfelder Christoph (glc) wrote: >>> Hello Jeff >>> >>> Unfortunately, a frame must be searched for the trailer to recognize it as >>> PRP frame. But I see no problem to have it disabled by default. >>> >>> >>> Best regards >>> >>> Christoph Glattfelder >>> >>> Z??rcher Hochschule Winterthur >>> Institute of Embedded Systems - InES >>> >>> Technikumstrasse 9 >>> Postfach 805 >>> CH-8401 Winterthur >>> Tel. +41(0)52 260 69 74 >>> >>> [EMAIL PROTECTED] >>> >>> >>> -----Urspr??ngliche Nachricht----- >>> Von: Jeff Morriss [mailto:[EMAIL PROTECTED] >>> Gesendet: Montag, 16. April 2007 10:26 >>> An: Developer support list for Wireshark; Glattfelder Christoph (glc) >>> Betreff: Re: [Wireshark-dev] Parallel Redundancy Protocol (PRP) dissector >>> >>> >>> >>> Meier Sven (msv) wrote: >>>> This is a dissector for the Parallel Redundancy Protocol (PRP) defined >>>> in chapter 6 of the IEC 62439. >>>> >>>> PRP uses two independent networks in parallel and allows redundancy >>>> without switchovers. >>>> >>>> The protocol is sending Mac multicast messages with Ethertype 0x88fb. In >>>> addition to that it adds to every Ethernet frame a 4 byte trailer before >>>> the FCS. The trailer is detected by checking a size field and an >>>> identifier which are part of the trailer. Therefore, if the last 4 bytes >>>> of a frame match a correct trailer they get interpreted as a trailer, >>>> although it was probably not a real one. >>> Is there some way to know if the trailer is going to be there without >>> searching for it? As it is, registered as a postdissector (didn't even >>> know those existed until now), this dissector will get called for every >>> frame--which seems a bit excessive to me. >>> >>> If there's no way to know ahead of time, maybe this dissector should be >>> disabled by default, though I'm not sure how to best go about doing that. >>> >>> >> _______________________________________________ >> Wireshark-dev mailing list >> [email protected] >> http://www.wireshark.org/mailman/listinfo/wireshark-dev > _______________________________________________ > Wireshark-dev mailing list > [email protected] > http://www.wireshark.org/mailman/listinfo/wireshark-dev > _______________________________________________ Wireshark-dev mailing list [email protected] http://www.wireshark.org/mailman/listinfo/wireshark-dev
