command to know the application running of the port

Hi,

is there any command to findout that which application is using the particular port.
or whether any port is occupied with the specfic process id ?

you can use lsof utility for this.if you are using solaris os.

Sunfreeware - Free and Open Source Software (FOSS) for Sun Microsystem's Solaris

am using the red hat
how can i know that ?

See, this is why it's usually a good idea what system you're using, what shell, etc...

On Linux, you can do (as root)

netstat -antp

to list all TCP connections (numerically) and the associated processes.

hi

on Hp UX you can find the same using

netstat -an | grep LISTEN which gives a less cluttered result.