On 9/5/06, Sam Hartman <hartmans-ietf@xxxxxxx> wrote:
There are a lot of complexities--for example while we hope every IP stack works with every other IP stack, two machines may not share a common upper-layer protocol or application protocol.
I worry that such text will encourage sprawling specifications that make requirements across many layers. I think the example you give is a little misleading, since it can be harmful for specifications to make requirements on lower layers as well. For example, HTTP requires a reliable transport, but I think it's good that RFC2616 does not include text like "HTTP implementations MUST support TCP/IP, but may support other transport protocols". In other words, universal interoperability will not be achieved by making RFC2119 demands in documents. It can be achieved by writing small documents that confine themselves to one layer. -- Robert Sayre _______________________________________________ Ietf@xxxxxxxx https://www1.ietf.org/mailman/listinfo/ietf