Verify the TCP port is open on a server

[Guest_imported]

Hi !

Could anyone please help on this issue.

1. How can I find whether a particular TCP port (Port Number is 1571) is open on a remote router (CISCO 1600) over internet ?

2. How can I find which application is using a specific port number on a remote server ?


Thanks.

 

[fenris]

1) What you need is a port scanner. If you are using Linux nmap is the best! Otherwise you will have to find some substitute. Alternatively you could try telneting to that port. telnet 192.168.0.1 1571

2) As for determining which program is on which port is a more difficult task then determining which ports are open. I believe that all the best port scanners have the ability to take educated guesses as to what type of software may be located on a particular port, they don't however know what the exact software is. If you wish to know what software is using which ports on a local machine, then this may be easier and probably would require a packet filtering firewall.


Troy Williams B.Eng.
fenris@hotmail.com

 

[gunthnp]

a free scanner for windows that i like is superscan it will tell if it open or not. So long and thanks for all the fish.

 

[sobak]

One quick and easy way I check is to use a telnet session and place the port number in for Telnet. You may only receive a blank screen but if it connects then the port is open.

david e