Our main office is connected to several smaller sites using MPLS circuits (1gbps handoff here at the main office, shared with 9 smaller sites each with a 1gbps handoff) All network services come through the main office (voice, lan, internet). On occasion we get complaints about slow internet at the sites. I have done iperf testing from our main office to the sites (and vice versa) and found speed to be within an acceptable range. However, I recently found a repeatable way to show that there IS actually a problem. There is a 60MB file hosted on icloud that is almost impossible to download at any of our MPLS supported sites. I can download this file from our main office without issue, it takes only a moment to download the full 60MB file. With 100% consistency, when I attempt to download this file over the MPLS circuit it never completes or takes a LONG time. I have ruled out our content filter as the source of the problem.
Most other internet traffic seems to work just fine (certainly there must be more problem traffic I just have not identified it).
Any ideas? I used wireshark to capture traffic but I am not well versed in packet analysis. It looks terrible though, tons of black. TCP Out of order, TCP retransmission, TCP Dup Ack, TCP Spurious Retransmission. Filtered based on the IP of the host and of Apple 17.x.x.x it's over 3mb for 17seconds of interesting traffic.
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