Adding Port to Ping

Question

I am using VB.net to ping a domain/IP, using the following code;

My.Computer.Network.Ping(Address, 1000)

I now want to add a port to the domain/IP - e.g google.co.uk:21

How would I go about this?

Answer 1

You cannot ping a port but you can try to connect to a specific port using either TCP/IP or UDP. The port concept belongs to the transport layer of the protocol stack (either TCP or UDP) while the ping is at the lower network layer (the ICMP protocol).

Answer 2

You don't, because that's not how ping works. There's no concept of a port in the ICMP protocol.

If you want to see if a port is open on a server, you must attempt to connect to it using TCP or UDP (depending on the protocol expected for that server). There's no other way to check for an open port.