This matches the timeout used in linux:
https://linux.die.net/man/5/dhclient.conf
This resolves several issues noticed during testing when we
have a very large number of devices that try to get an IP address
around the same time.
The dtls test already has the ability to retry upon a UDP failure.
However the sockets are currently configured to be blocking and to wait
forever. I added a timeout of 1.5 seconds in order the test to correctly
timeout.
Sometimes when under heavy load, the CI machines can take a significant
amount of time to bring up a python process (~10s). The timeouts for
the network tests were chosen without much thought, and didn't leave
much room for this sort of delay.
This patch brings up timeouts for ntetwork tests 20s -> 60s
Dynamic buffers gives the network stack the maximum throughput while
still supporting smaller devices. This should expose the largest number
of issues across differently sized platforms.
Additionally, restructured the UDP tests to avoid unintentionally flooding
the recieving side with bad data after failed packets.
Also, added a bit more documentation
Added test for the pattern of packets used during the DTLS
handshake. This pattern (5x ~300 byte packets) has been very
problematic for new network interfaces.
Brian Daniels
Christopher Haster