Clarify the concept of end-point

[cabo@…]

Cullen Jennings notes (msg03073c):

Section 3.5. I don't think you can remove a client from observer list based purely on source IP, you need to use source IP and source port. Without this two different clients behind a NAT would remove each other when talking to a server outside the NAT. Similar problems with moor than one coap client on the same host. Same issue in section 4.1 when adding a lint to lis of observers.

->

Clarify that "client" here is a subclass of "endpoint", which is identified by its transport address (IP address/port) and security association.

[cabo@…]

This should not be solved in -observe, but needs to be clear in main
-coap. (Observe should then add a pointer to the relevant text,
e.g. in its introduction.)

Define in -coap that end-point is identified by its IP address, port
number, and security mode/context. Define what the latter is for the
security modes we define.

Make sure that similar editorial pointers are added to -coap where
necessary.

[cabo@…]

Also: Section 4 of -observe defines the conditions when a client is removed from the list of observers. Clarify: When DTLS is used, the client must also be removed when the DTLS end-point ceases to exist, i.e. the session ends.

[hartke@…]

Done in -coap-10. The remaining action items relate to -observe.

[hartke@…]

Fixed in [865]:

Close #224: Done in observe-06