Re: Minimum length of DHCP packet ?

[Eric Weber <[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.

-- Eric Weber
   [e-mail]