We have two offices with BT (I know, BT wasn’t my choice of isp either) ADSL connections. Until yesterday both were using a combination of Dlink routers and Cisco Pix firewalls. The Dlink router was acting as the DSL modem and the pix providing firewall and site-to-site vpn connectivity for the two offices. Today, we replaced the Dlink routers and Cisco pix units with Draytek 2830 routers and configured ipsec site-to-site vpn links. Within minutes users were complaining that performance over the vpn link was much slower/laggy (they mainly use terminal services/remote desktop). It's now been running for several hours as we were hoping things may settle down but the performance hasn’t improved. The internet connections/links are the same ones, we've simply replaced the old router/firewall with Drayteks!

Has anyone seen any similar issues? Are there optimum dsl or vpn settings we should look at? I'm not convinced the dsl connections are registering as fast on the Drayteks as they were on the Dlinks. We should have checked this before hand i supose but it will cause pain and disruption to mess about with them now.
As i understand the pix units have hardware accelerated encryption which may explain some of the differnce, however, the site-to-site vpn links via the Draytek seem horrendously slow in comparison to the previous setup. Surely something is a miss?

Hi,

Try updating your Vigor2830 firmware (latest beta), i'm sure it wil fix your isue.

regards,

rj

The only time I have really had problems like this is either with the ISP performance or MTU settings. Compare the MTU of the old DLink router with the setting in the Draytek and see if there is a difference. I must admit I haven't had to change the MTU on my Draytek but then my ISP is not BT...