On May 3, 2011, at 1:38 AM, Rémi Després wrote:
>> I also am confused by your use of the term "datagram". A datagram is not a 
>> transport layer construct,
> 
> Isn't User Datagram Protocol a transport layer protocol?

Yes, and unless the datagram is carried in IP, it's not actually a datagram. I 
refer you to the definition of the term. A datagram is self-addressed and 
contains all of the information necessary to deliver it from its source to its 
destination.

>> it's a network layer construct. 
>> http://dictionary.reference.com/browse/datagram
> 
> To know what a datagram is in IETF, RFC's are IMHO better than an online 
> dictionary

If you want to play that game, so be it. The word "datagram" (along with 
"catenet", which has largely been replaced by the term "internet", in lwer 
case) was common in the 1970's and 1980's, and the definition was well known to 
those present. So I don't find a place that says "when I say 'datagram' I mean 
'...'" in the RFC series - that was in published conference papers circa 1972 
when the datagram model was first being proposed as an alternative to virtual 
circuits. What I do find, however, is this in IEN #48. The Internet Engineering 
Notes (IENs) were  a parallel document track used in the 1970's. IEN #48 is 
"The Catenet Model for Internetworking", written by Vint Cerf. It says, among 
its assumptions, that 

        it is assumed that the
        participating network allows switched access so that any source
        computer can quickly enter datagrams for successive and different
        destination computers with little or no delay (i.e., on the order
        of tens of milliseconds or less switching time).

        Under these assumptions, we can readily include networks which
        offer "datagram" interfaces to subscribing host computers.  That
        is, the switching is done by the network based on a destination
        address contained in each datagram passing across the host to
        network interface.

A datagram is, unlike a packet carried in a virtual circuit, a message that 
carries its own destination address and can therefore be routed by the network 
without setting up such a circuit first.

> I hope the IESG won't accept your new interpretation.

Well, if they have a problem with it, they can ask the designers of the 
architecture for their opinions. "Datagram" is a well known and well understood 
term.

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