Re: Minimum length of DHCP packet ?

Mike Carney - Sun BOS Software <Mike.Carney@east.sun.com> Fri, 08 March 1996 16:48 UTC

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From: Mike Carney - Sun BOS Software <Mike.Carney@east.sun.com>
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To: tomy@sfc.wide.ad.jp, dhcp-v4@bucknell.edu
Subject: Re: Minimum length of DHCP packet ?
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> I remember that there was description about minimum length of DHCP
> packets in old I-D.  But newest I-D doesn't specify minimum length.
> 
> DHCP message should be greater than 300 octets (= BOOTP Packet), is it
> correct?  Or is it harmful to discard packets shorter than 300 octets?
> 
> Keio UNIV.
> WIDE Project.
>                       Akihiro Tominaga (tomy@sfc.wide.ad.jp)
> 

We've discussed this  issue at great length on this alias, but 
unfortunately, the spec isn't clear on this point.

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).

Mike Carney
SunSoft PC Networking
Chelmsford, MA