Linux-Hams archive - April 1997: AX.25 references/documentation

AX.25 references/documentation

Mike Bilow ()
Thu, 10 Apr 97 11:58:00 -0000

Terry Dawson wrote in a message to Mike Bilow:

TD> AX.25 is based heavily on the datalink protocol specified
TD> within X.25, which is based on HDLC. Most of the X.25
TD> specification is completely irrelevant to AX.25.

TD> AX.25 + Rose is much more closely related to X.25, but there
TD> are still some significant differences.

I consider this a fairly good summary of the situation.

TD> How official does it need to be ? There is a published
TD> specification backed and supported by a demographic
TD> comprising the community that use it. Sounds official to me.

The AX.25 specification as published by ARRL is recognized explicitly in the
U.S. government regulations. I have no idea what the laws are elsewhere.

TD> X.25 is a C.C.I.T.T. recommendation. ANSI have nothing to do
TD> with it. I think ISO-8203(?) is the ISO standard.

CCITT is now ITU-T, an international organization established by multilateral
treaty whose members are directly accountable to national governments (or to
national telephone and telegraph authorities). The main purpose of ITU-T is to
make sure that telephone and telegraph operations of different countries can be

ISO is a membership organization comprised of national representatives, and
ANSI is the U.S. member of ISO. Such members are usually industry or trade
consortia, as is ANSI, rather than governmental organizations. It is common,
at least in the U.S., for laws to incorporate ANSI or ISO standards by
reference, especially where health and safety are concerned.

TD> Actually, recent discussion leads me to eblieve this isn't
TD> actually very true. There are a number of 'extensions' to
TD> AX.25 that are not 'official' in the same way the AX.25
TD> specification is. It would be a profitable and useful
TD> exercise I believe to at least collect and document these in
TD> an attempt to standardise them.

I strongly agree.

-- Mike