I have a couple of customers that have
been complaining of issues on their circuits, an issue that causes them to have
problems with large file transfers. The only noteworthy problems in their data
streams seem to be TCP Dup Acks – I’ve seen as many as sixty, or
over a hundred, in file transfers of 100 MB test files. However, as near as I
can determine, these errors are being introduced in the Internet, outside of
our network (the customers use VPNs over internet circuits with major carriers
for these file transfers).
As I said, we’ve tested our own
network thoroughly, but I’m at a loss as to where to go with this issue.
Obviously, telling the customer, “It’s not our fault” is
unacceptable, as that doesn’t move them any closer to error-free file
transfers. On the other hand, I’m not sure where to tell the carriers’
help desk technicians to look for the source of this issue. Has anyone seen
this before on Internet circuits, and is there some way I can use Wireshark to
help pinpoint the issue more specifically than telling the carrier, “It’s
in your cloud”?
Thanks,
Roland
Volz
Network Engineer
Data Access/Datapatch,
Inc.
40 Eisenhower Drive
Paramus, NJ 07652-1404
(201) 843-5468 x7032
www.Data-Access.com