> On 31 Oct 2016, at 16:06, Richard Cochran <richardcoch...@gmail.com> wrote: > > On Mon, Oct 31, 2016 at 02:07:01PM +0100, Delio Brignoli wrote: >>> @Delio, I see you allow announce without the TLV: >>> >>> >>> https://github.com/audioscience/linuxptp/commit/0b6d8ca73332391af9bddc25177df254b066d669 >>> >>> Can you tell us why? >> >> This is tricky because in some places 802.1AS-2011 seems to imply a >> TLV is mandatory but when you dig down into the implementation >> details you find that: in 10.3.13.2.1 (f) txAnnounce() appends the >> TLV *only if* it doesn’t exceed the transport’s MTU and in >> 10.3.10.2.1 (c) and (d) qualifyAnnounce() accepts an announce >> message without a TLV. So a TLV is present *if* it fits in the >> transport’s MTU but a compliant implementation has to accept an >> announce message without path trace TLV. > > Those passages permit dropping the TLV when it would cause the message > to exceed the frame size. Let's do a little math. [...] > Was the switch you had operating in such a large network?
Or the MTU may be artificially restricted, who knows... but I am not saying linuxptp should be changed to conditionally drop the TLV. > If the TLV is missing, chances are that the sender is out of > compliance, don't you think? Yes, but I stated as much in my previous message: the switch was not compliant. However, linuxptp isn’t compliant either on the RX side which is the reason for my patch. Regards — Delio ------------------------------------------------------------------------------ Developer Access Program for Intel Xeon Phi Processors Access to Intel Xeon Phi processor-based developer platforms. With one year of Intel Parallel Studio XE. Training and support from Colfax. Order your platform today. http://sdm.link/xeonphi _______________________________________________ Linuxptp-users mailing list Linuxptp-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linuxptp-users
