WinSock packet loss & Disconnection by itself with no reason

Hi I am in need of help,

I am developing a winsock application ( one server and many client type (TCP/IP)) in VB6.0. I have my server in a network ( I have already done port forwarding in the router).

The server side Internet connection is (static ip ).
When I connect from out of network, say modem, the packets from either side fail to reach the other (intermittently). though I can get connected and have two way communication and request for disconnection leaglly.

I confirm that the either side internet connection does not get disconnected as I have other realtime application doing fine. And I can reestablish the winsck connection with out restarting the modem(client side). The server application still accepts connection without restarting the application (server or client). I can disconnect winsock forcefully too.

1) server and client is on the same pc (working well for weeks with no problem )

2) server and client on the same internal network (working well for weeks with no problem )

Is it somthing to do with the Lan and Switch settings?

I am using aztec adsl modem and linksys router. have 7 computers attached to the router.

local mask 255.255.255.0

My server is WIN 2000.

As we can see that the communication was good, both when done in the same pc and when done in the same network. The problem appears OR becomes more apperent when done in the Internet

I am tired asking for help and spending nights at my pc, please help, my boss will be up to my neck soon. No one have given me soln yet.

Could you clerify for me where is the server and where is the client? for instance is your server at your house behind the linksys router and you are like dialing up to connect to it? or is the server at your work location and you are going through your linksys at home to connect to it? what if any firewalls are installed? what model linksys are you using and who is your dialup isp? Did you trace to your server and check for latency or do an extended ping to verify no packet loss?

Hi,

Server is at office, Concection = "internet" --> "adsl modem" --> "linksys router" --> "server PC"

I was told that presently the local gateway & address comes from the modem and not the router(255.255.255.0)(10.0.0.2).

P.S.(7 other normal PCs are also connected to the router.)

Server is always ready for connection, client will allways connect from out of local net work.

There is no fire wall installed but I will after getting it all right.

I am in Singapore, provider is Singnet.

Ping test is pass.

I will get for you the model number and other details at your specific request, thanks a million