Jon Shallow ea72c3d770 Limit outstanding CON requests to NSTART per session for congestion control ...

https://tools.ietf.org/html/rfc7641#section-4.5

In order not to cause congestion, servers MUST strictly limit the number of
simultaneous outstanding notifications/responses that they transmit to a given
client to NSTART (1 by default; see Section 4.7 of RFC 7252 [RFC7252]).
An outstanding notification/response is either a confirmable message for which
an acknowledgement has not yet been received and whose last retransmission
attempt has not yet timed out or a non-confirmable message for which the
waiting time that results from the following rate-limiting rules has not yet
elapsed.

Delay sending of PDUs if active CON request waiting for ACK.

Do not start of another Observer unsolicited response if active CON waiting
waiting for ACK.

Display outgoing PDU if log level DEBUG or higher to help troubleshooting.

This does not fix the ratelimiting of non-confirmable messages, which
should be handled by the application.

2018-07-10 14:11:32 +01:00

..

coap

Limit outstanding CON requests to NSTART per session for congestion control

2018-07-10 14:11:32 +01:00