Hi,

here it is : in my company we're discussing about configuring vpn tunnels. We work with government and thus use its WAN. Nowadays we only use encrypted protocols, but would like to use snmp, ftp and other common uncyphered protocols.

The wan is only 128kbytes/s in some agencies, so I was wondering wether setting on VPN would increase the traffic load...

I know the main problem is usually cpu load, but in my case, that shouldn't be a problem because we've got recent machines.

Since we're on a private WAN, I think using low level encryption would be enough (simple des).
So question 1 :
Will des really be lighter than aes ? or does this affect only the cpu use ?

I know that a part of overhead will come from ISAKMP, but I thought configuring a 24 hours rotation time or so.
Thus question 2 is :
Is this a huge security hole, or does this sound acceptable ?

I'm not sure about the security of your ISAKMP settings, but what I can tell you is this: network overhead for VPN is negligible. Encrypted data is 1:1 in size with the raw data, so the only overhead is that that makes up the VPN protocol. Very little.

Thanks for your reply.

I thought there was no reason that encrypting data should increase its size, but when realizing, I didn't want to take the chances.

Bye