>From: "Craig Whitmore" <lennon@orcon.net.nz>

>I have a couple of customers with M1122 over the last week and lately they
>cannot access some secure sites properly. Its REALLY slow to alot of them.
>Other normal sites if perfectly well.(and the non-secure parts of the
>websites work prefectly well). When they changed over to an Alcatel Pro,
the
>problem went away straight away. Has anyone had this problem before or know
>of the problem?

Common causes:

1. PMTU Discovery is broken
2. Client side not answering a ping.
3. Packet loss (affects mainly International secure sites)
4. Client IP has no in-addr.arpa resolution.

Issues 2 and 4 usually only affect the first visit to the site, some TCP SYN
flood logic may test to see if you exist and may wait for a retry of a SYN
packet.

Packet loss on high RTT links is evil, you go from one second to one minute
response times with just a 1 or 2 % packet loss. This is our most common
complaint for users of wireless links (slow international HTTPS sites).

The fact that the Alcatel fixes the problem tends to suggest that it is some
ICMP traffic that is being broken by the M1122 (or are these overseas sites
?).

Cheers

BG.

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Received on Tue Oct 2 13:35:17 2001