I’m using Zeroshell as an alternative to normal routers/gateways/firewalls in a university project and I have to say that I’m delighted with it. I found it to be a great piece of software and much more flexible than any other solution using expensive routers.
My question is about bandwidth loss when using a lan-to-lan VPN.
I have two PCs (PIII 1000MHZ, 512 MB RAM) with several NICs each acting as gateways of two different sites. Both machines are connected via 100 Mbps Ethernet and I can get an effective bandwidth of 96 Mbps. After that I created a lan-to-lan UDP VPN to connect both PC (through the same ethernet link) and tested for max bandwidth with the following results:
Encrypted and compressed VPN
Encrypted VPN (no compression)
VPN (no compression nor encryption)— 47 Mbps
Are those values acceptable? I didn’t thought that I would notice such a big loss of bandwidth when tunneling the traffic through the VPN.
The CPU usage didn’t went beyond 50% during any of the bandwidth stress tests so I assume that the problem is not related to the machines. All my NICs are 10/100 3Com branded and seem to be working OK.