In Ubuntu, how do I figure out which process is a network pig

Using top it's easy to identify processes that are hogging memory and cpu, but ocasionally I see my computer's network activity spike, but I'm unable to determine which process is generating the activity. Where is the right place to look for this information?

From stackoverflow

• You can install several applications to monitor network traffic in real time. NTOP, tcpdump, trafshow, iptraf.

  I would go with NTOP or IPTRAF. But that's just a personal taste.

  Also, with Linux's netstat you can use the -p flag to see how many connections is a process using.

• The package 'ntop' provides a comparable tool to top. The design's a bit different since the kernel doesn't provide excellent statistics via /proc.

  Description: display network usage in web browser
   ntop displays a summary of network usage by machines on your network in a
   web mode, which allows the display to be browsed with a web browser.
  

• Small correction to Pablo Santa Cruz-

  On linux: netstat -p gives the pid of the program running on the port. On BSD: netstat -p is used to specify the protocol.

• Hello,

  You can also take a look at "NetHogs": http://nethogs.sourceforge.net/. Little yet very handy utility. Especially if you want to find out which process is taking the bandwidth.

  Maxim Veksler : +100 vote on this answer.

• Hi.

  You can also use iftop. In Ubuntu you can install it by typing in terminal: sudo aptitude install iftop. To use type: sudo iftop -i eth0, where eth0 is your network interface.