Network traffic monitoring, network connection speed, wifi, wlan, Iperf - test connection

Monitoring

iftop - shows horisontal bars of transfers
http://ex-parrot.com/~pdw/iftop/

iptraf - shows statistics, possibility to filter etc.

netwatch - shows hosts, incoming and outgoing

slurm - colorized display of one interface, for example: slurm -i eth0

wavemon - shows wifi/wlan statistics

Speed

To find interfaces do:

ifconfig -a

To find connection speed (ie 1000Mbit) do:

ethtool <interface>

For example: ethtool eth0

To watch statistics and current speed do:

slurm -i <interface>

For example slurm -i eth0

Iperf - test connection speed

On the server side, run:

iperf -s -w 128K

On the client side, run:

iperf -c xxx.xxx.xxx.xxx -w 128K

(Where xxx.xxx.xxx.xxx is server IP address.)

-w controls TCP window.