Re: Minimum length of DHCP packet ?

["Pratapa Reddy P." <[e-mail]>]

>Akihiro Tominaga writes:
>> DHCP message should be greater than 300 octets (= BOOTP Packet), is it
>> correct?  Or is it harmful to discard packets shorter than 300 octets?
>
>Mike Carney writes:
> > Since DHCP is intended as "BOOTPv2", and thus leverage the already BOOTP
> > relay agent capabilities out there, the size should be greater than or
> > equal to 300 bytes. I've seen some relay agents discard packets less than
> > 300 bytes (the BOOTP spec specifies that BOOTP packets must be 300 bytes in
> > length).
>
>I see no reason why anybody should deliberately disregard a packet
>smaller than 300 octets, if it is large enough to contain a valid DHCP
>message.  While it certainly makes sense for clients to pad everything
>they send out to 300 octets, I don't see why it makes sense for
>anybody to reject an incoming message because it came from a client
>that didn't do such padding.
>
>Therefore I would advise the original poster NOT to discard packets
>shorter than 300 octets, if they can otherwise be parsed.


I remember Apple's Open Transport (DHCP client) sends packet less than 300
bytes. If no server responds to it, then it tries with larger packet size.
This looks strange, but it's doing that way :(.
I feel it is better if server doesn't discard packets with lesser size than
300 bytes. This is just my opinion.

Pratap
[e-mail]