[En-Nut-Discussion] ICMP echo request response failure on ARP cache timeout

[Harald Kipp]

Hi Michael,

Michael Jones wrote:

> Also, I want to point out that we use an extra thread for DHCP in our
> systems. The current implementation does not handle DHCP in large
> environments very well, does not cope with delayed network startup and does
> not handle DNS and TimeServer updates via DHCP at all. Maybe we could build
> an extendable Network thread that could have various aspects plugged into it
> on demand? That would lower the overall "cost" of this thread.

This is one reason why DHCP needs a major rewrite. The other one is,
that it is a monster, code-size wise. I assume that the main loop is too
complicated for the compiler's optimizer. Furthermore, DHCP
automatically links to DNS, which is not needed by many applications.
Modularization is the magic word.

Also Nathan suggested some kind of general purpose network thread.
Sounds attractive, but quoting Nathan: There may be "other subtle
implementation issues with this as well."

Don't panic! I should have added to my previous post, that I do not have
the intention to redesign the whole network stuff right now. But we need
to think about _all_ possible improvements early to know which way to
go. My idea is to create a new set of network libraries, living
concurrently with the existing ones. It should be up to the application
developer whether he wants to change or keep the old version.

I'll start playing around with a "per-interface tx thread" and see, how
it develops.

Harald