VPN specific Application slow

[bigdavelamb]

Hi, I have a nightmare vpn issue. I am using Cisco 501PIX units on a site to site vpn, they both have Linksys WAG54 modems at each site. My vpn works fine, can login into domain server across it OK, and can FTP at speeds of around 20KB/SEC. But I have an application (an Alarm application called Velocity, it is a client/server application, and the client posts records into a sql database thru the vpn to the server. But it is taking around 20 seconds to add a record, on the lan it takes 2. I have adjusted the MTU and TCPWindowSize but to no avail. I have tried using SQL enterprise manager thru the vpn and that works perfectly. I have measured the bandwith each transaction takes with the programme and it is tiny so i cannot see it being a bandwith issue.

How else can I troubleshoot this problem?! Anyone know as I have been doing this on and off for weeks now!

Thank you.
Dave

 

[Donkey1]

Dave,

I have had the same issues as you. We tried to run a client/server access db across a vpn connection without any luck. Reading up on the subject it says that this sort of thing is not recommended over vpn due to overhead/latency issues etc.

You may have to look else where for a solution other than vpn for this sort of application.

Andy.

 

[force5]

Dave, are you using an SSL VPN? Also, what type of IP addressing scheme are you using? If your router has to do translations, that also effects things. Also, how strong is the encryption that you are using? The performance requirements for the VPN are a function of the packet arrival rate, the strength of the encryption, and the capacity of the Internet connection at the tunnel termination point in the central office. In short, VPN's are nice but was not primarily designed for some of the things that we "expect" them to do. VPN's do not use TCP/IP, that is why your LAN and FTP is so fast. Have you thought about using Terminal Servers with possibly a Load Balancer? You could set the Terminal server<s> to only have the client application on it while the main database will reside on your main server.?!?!

 

[technome]

Will go along with force5, I would not think of running an application over VPN, Terminal services is the way to go.

If it only for someone with Admin status, add the Terminal services to the 2003 server or RDC to a wks. Normal Vpn access is OK for accessing small files; unless you have massive bandwidth using VPN for application access is dangerous.