16 Jun
2024
16 Jun
'24
8:08 p.m.
On Jun 15, 2024, at 5:50 PM, Keith Halewood
<Keith.Halewood(a)pitbulluk.org> wrote:
Hi,
I think there’s a bug in in decnet/nsp.py, line 1173
A phase 3 accept is setting its state to self.cc <http://self.cc/> which doesn’t
seem to exist. If I change that to self.run, like the state setting for phase 2 accept, I
can then send a message after accepting the connection without ‘WrongState’ being thrown.
This is pydecnet 1.1-648.
Keith
More on this: there's an assymetry in the 3-way handshake: the initiating side can
start sending data as soon as it receives the accept (that data doubles as the confirm
ack). But the responding side has to wait for the connect confirm to be acknowledged
before sending any data. This asymmetry makes some sense because most applications have
the initiating side sending the first data message. But if you have an application where
the responding side sends the first data message you have to wait for the ack. The
simplest way is to catch the WrongState error and retry after a brief pause.
paul