Hello, On Thu, Feb 10, 2011 at 6:46 PM, Guy Harris <[email protected]> wrote: > > On Feb 6, 2011, at 10:17 PM, M.Baris Demiray wrote: > >> Unfortunately no, there is not. As in SIS Layer dissector this is also >> a part of a standard which is available only to NATO member states > > Hey, I'm a citizen of a NATO member state.... :-)
Oh. :) But I would prefer to depict a DPDU header by words rather than sending the part of the document (especially if DPDU headers are kept intact in the new version, keep reading, explained in the next paragraph) before ensuring that I'm authorised to do that. >> and that therefore we access through an account. However there is a >> version called 1.0.2 on the Internet and there you may find the >> section C.3 Structure of sublayer protocol data units (D_PDUs) in >> order to observe what a DPDU header looks like. This is a really old >> version and I think that's why it's unclassified. Here is the link, >> >> http://www.armymars.net/ArmyMARS/HF-Email/resources/stanag5066.pdf >> >> Besides this I will check if I can provide any recent versions of DPDU >> headers. > > OK, so the packets in this file are D_PDUs as described in that section? Exactly, I've just compared DPDU headers described in two versions of the document and the only difference is the new content of Extended Field of Type 6 Management DPDU which was introduced by HFTRP (HF Token Ring Protocol) to hold information such as Ring Address and Number of Nodes in the Ring. And it's not a new field, just an extended field placed by setting the Extended Message flag (p. 19). > Do they begin with the 16-bit synchronization sequence, or is that stripped > off, so that they begin with the header field? Do data PDUs include the CRC > at the end, or is that stripped off? 16-bit synchronization sequence is sent over-the-air for all the types of DPDUs so it's not stripped off. And for data PDUs, yes, they include CRC at the end. So it's like below for data PDUs, | SYNC | HEADER | HEADER_CRC | DATA | DATA_CRC | And like below for control frames (namely DPDU types 1, 3, 5, 6, and 15), | SYNC | HEADER | HEADER_CRC | Cheers, > - > This is the tcpdump-workers list. > Visit https://cod.sandelman.ca/ to unsubscribe. -- M. Baris Demiray Researcher TUBITAK-UEKAE/G227 Design and Development Engineering Division Tunali Hilmi Cad. Binnaz Sok. No:2 Kat:3 06700 Kavaklidere, ANKARA, Turkey Phone : (+90) 312-427-73 66 ext 128 Fax : (+90) 312-427-88 44 - This is the tcpdump-workers list. Visit https://cod.sandelman.ca/ to unsubscribe.
