[Babel-users] unicast attempt breaks timestamping

[Juliusz Chroboczek]

>> Based on the patch juliusz supplied me to enable unicast IHU, and
>> 
>> default enable-timestamp true
>> 
>> this stops sending timestamps (which apparently relies on hellos and
>> IHUs being bundled together)

> Can you provide the patch in question?

I cannot find the original patch, but it basically consists in always
taking the alternative (else) branch in the conditional at line 1666 in
message.c.

> Is there any reason why you couldn't send hellos alongside the IHUs?

Yes, Hellos cannot be sent over unicast in the current protocol.  So if
all IHUs are sent over unicast, the timestamps are ignored.

I see two solutions:

  - extend the IHU timestamp sub-TLV to allow an optional timestamp,
    perhaps only used when sent over unicast;
  - extend the protocol to allow unicast Hellos.

We could do both.

-- Juliusz