Louis Pouzin at INRIA coined the term datagram for use in his CIGALE/CYCLADES network around 1974. vint At 07:17 PM 9/23/2002 -0700, Dave Crocker wrote: >At 06:46 PM 9/23/2002 -0700, Fred Baker wrote: >> A packet is a unit of data carried in a packet network, > >this just moves the question over the definition of a packet network. (I was trying to compress things.) > > >> regardless of the layer. For some reason, we generally refer to layer two packets as 'frames' (such as Ethernet, Frame relay, or LAPB 'frames'), X.25 packets as 'packets', and TCP packets as 'segments'. > >please note your use of the word "generally". as I said, use of these terms is flexible. > > >> I can point out literature that refers to each of those as 'packets'. > >that was my point. > > >>But a datagram is quite clearly defined. > >I believe the term datagram predates IP and seem to recall hearing it during the late 70's and early 80's in non-IP venues. > >The fact that it is well defined for one use does not mean that the definition is, well, definitive. > > >>...from the application's perspective, a wad of data is directed to a specified destination, and the application can essentially fire and forget. >> >>I could imagine the APEX folks using the term "datagram" in that latter sense. > >indeed locking the term down for Apex is probably the more useful path. > >(but it is slightly amusing that your definition is the same as I used for packet-switching...) > >d/ > > >---------- >Dave Crocker <mailto:dave@tribalwise.com> >TribalWise, Inc. <http://www.tribalwise.com> >tel +1.408.246.8253; fax +1.408.850.1850 Vint Cerf SVP Architecture & Technology WorldCom 22001 Loudoun County Parkway, F2-4115 Ashburn, VA 20147 703 886 1690 (v806 1690) 703 886 0047 fax