Have an unusual condition and trying to find a mechanism that would cause this.
Have a Internet location where download wilsl randomly slow until near complete stop. Not everyone, by a too high percentage. All major sites show issue... Microsoft, McAFee, CNet, Youtube, anything.
We've done Wireshark captures. There are no retransmissions, no corrupt packets, no loss. The delay between packets will logarithmically increase until it quickly reaches 120 seconds. From the client's perspective
Received packet from Microsoft. ACK sent immediately EXACTLY 120 seconds Received packet from Microsoft. ACK sent immediately EXACTLY 120 seconds Received packet from Microsoft. ACK sent immediately
The delay incremented in one test as so rapdi exchange of packet for the first two seconds, then @2.1 seconds @2.3 seconds @2.5 seconds @2.9 seconds @3.1 seconds @3.9 seconds @4.2 seconds @5.9 seconds @9.4 seconds @16.4 seconds @30.3 seconds @57.8 seconds @112.5 seconds @221.7 seconds @342.0 seconds @462.4 seconds @582.6 seconds ... every 120 seconds for next half hour--then capture closed
120 seconnds is clearly a timer of some sort, but I can't figure out what would cause a service to hold off sending the next packet for 120 seconds... Or what device would buffer such a thing for 120 secs.Again, no re-transmissions. Each packet is a new packet, different. the transfer continues at a rate of one 1,514 byte packet every 120 seconds. This is happening to servers, desktops & laptops across a site.
It only occurs with TCP transfers. We have UDP connections between the sites that are unaffected. Not affecting local LAN-to-LAN. SO the problem is either on our Cisco 2821 (WAN/Internet router) or within our ISP. ISP has been doing good faith tests and investigation without results.
Just fishing for ideas of what would hold back the next packet for 120 seconds, yet not be re-transmissions, corrupt packets, or loss of packets.