Socket programming: Security problems?, Ping works but connect deosn't Options

[rij]

Hello,

I am trying a simple client-server example between two machines (using socket programming). When I run the client, I get the error: "No route to host".

Now, here is what I observed.

I can ssh to the server from the client, but cannot telnet.
I can ping to the server from the client but cannot traceroute. Well actually it runs but I get the error: !X which I understand means that the admin is prohibited such communication.

So does that mean that:
1) I will be able to do only secure communication beteen the two machines?
2) BSD socket API is by default unsecure?
3) What is the best secure socket API to use?

Thanks a bunch in advance.

[michaelk]

Are these PCs on the same LAN?
Are you using hostnames or IP addresses? Try IP addresses instead.
Is the firewall if running configured to accept incoming data on your desired port and protocol i.e. TCP or UDP?

Typically the telnet server is not configured to run by default.
Do your client/server apps run as expected on the same computer.