[lwip-users] Re: [lwip] Initialization Sequence

[leon . woestenberg]

Hello Adam,

> I wouldn't recommend killing off all active connections just because the
DHCP
> client fails to get a lease, however! If your system has a short network
> outage at the "right time", i.e., just when it is about to renew its
address
> it might timeout and think that it didn't get a lease. When the DHCP
client

If DHCP is implemented right, this is not an issue:

Basically, a DHCP already tries to renew a lease somewhere halfway the
lease period
and can continue trying so, up to the end of the period.

Somewhere around 2/3 of the period, if it _still has not_ got a lease from
it's
previous DHCP server, it starts asking other DHCP servers for the remainder
of
the 1/3 period.

The whole DHCP negotiation procedure is much more complex, or at least much
larger
than described above, but is very robust.

Short network outages are not an issue.

Great that you brought this issue up; W*nd*ws 2K Professional's DHCP client
is actually
very non-robust in the respect of short network outages. It fails to lease
if the server
is not able to get it's response through a couple of times.

> best. Option 2 will make you receive all packets; an IP address of
all-zeroes
> means IP_ADDR_ANY. The reason for this behaviour is to allow DHCP clients
to
> boot with a network interface that accepts all incoming packets including

> DHCP offers.
>

Adam, this is really great! I already thought this would be the largest
amount of
work to implement, but if it's already there, great!

Regards, Leon.

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