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New Member

Very Slow VPN Connection - CISCO 1841

Hello There!

Having issues with a 128bit AES IPsec VPN, between two brand new routers with outside NAT setup

The simulated WAN VPN link is currently a linksys 10/100 switch for testing, and has also just been a crossover cable.

We are experiencing an average of 1.24mbit/sec when using the VPN connection, and 2-3mbit without using VPN. This is by monitoring the bandwith of PC's at each end passing data from one end to the other.

I have eliminated any issues with the client PC's, they happily pass 70-80mbit from each other by just using the switch.

The 1841's use about 20% CPU when VPN enabled, memory usage is also low.

What has already been tried:

A) No NAT - There is a slight increase, upto 1mbit extra.

B) Lower encryption - No real change

C) Different VPN Types - No real change

D) MTU set from 1300 to Auto - No change

E) Manually setting duplex speeds - No change

Any suggestions appreciated.


Jesse Moore

Everyone's tags (5)
New Member

Re: Very Slow VPN Connection - CISCO 1841

I take it there are no clues as to what may be causing this issue?

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