Subject: Re: ip reassembly time exceeded?
To: None <current-users@NetBSD.ORG>
From: Christoph Badura <email@example.com>
Date: 01/28/1997 03:11:00
dennis@jnx.COM (Dennis Ferguson) writes:
>Here's the top 10 IP packet sizes as measured from a backbone router
>Size (bytes) Probability (%)
> 40 44.8
> 552 9.2
>I'd conclude two things:
>(2) 296 is so frequently occurring that I wouldn't want to bet the problem
> is entirely the fault of the Microsoft software, as one would assume
> they would have had plenty of opportunity to notice by now and fix it
> (I'm pretty sure the 552 in second place is microsoft's preferred number,
> so there may be a lot of those machines out there).
The 552 being in second place has most likely nothing to do with
microsoft. Some BSDish TCP/IP stack default to a 512 byte maximum
segment size for non-local traffic. To qoute from /sys/netinet/tcp.h:
* Default maximum segment size for TCP.
* With an IP MSS of 576, this is 536,
* but 512 is probably more convenient.
* This should be defined as MIN(512, IP_MSS - sizeof (struct tcpiphdr)).
#define TCP_MSS 512
Interestingly enough, this used to be 536 bytes in 4.3BSD.
Christoph Badura firstname.lastname@example.org
You don't need to quote my .signature. Everyone has seen it by now.
Besides, it doesn't add anything to the current thread.