575 LRE and data transfer problems
I have a connection from my provider using the Cisco 575 LRE, configured for 10 Mbit/s. I don't know the make and model of the switch but I assume it is likely a Cisco device also.
I'm experiencing problems with the LRE connection whenever big files are being transfered simultaneously in both down- and upstream directions to/from a PC. The data transfer may slow down to a stall and all WAN connectivity may become momentarily blocked. Transfer speeds and reliability always seem good as long as big files don't get transferred in both directions at the same time.
What could cause this problem? My service provider says that they see no problems in their end and they are unable to help me. I don't know how extensively they have looked into any possibility of problems though.
I've tried different 100Mbit network cards, replacing ethernet and phone cabling and changing duplex settings and MTU, but nothing has completely solved the problem so far. Forcing network cards to full-duplex does prevent the worst slowdown and hanging described above, but limits upload speed to around half of the maximum available.
Not sure if this is meaningful here, but my service provider claims they have the switch my CPE is connected to configured for full-duplex, but when I have a PC network card set to autonegotiation, it will always result in a 100baseTX half-duplex link with the 575 - this is the case where I get maximum speed in either one direction but also the mentioned problems with bi-directional transfer.
I don't know what more I can do to the PCs here to solve this problem and I don't have access to configuring the CPE device, because I don't own the switch it is connected to. I can only think of trying to ask my ISP to read this thread if someone has a possible solution that requires actions on their behalf.
Any help would be much appreciated.