Networking concepts

http://www.youtube.com/watch?v=EkNq4TrHP_U
-------------
tcpdump -i eth0 -nn -c 10 tcp and host 192.168.57.176
tcpdump -D , shows network interfaces available for capture
-------------

• etc/hosts file

     http://lifehacker.com/5817447/how-to-block-unwanted-ads-in-all-applications-and-speed-up-web-browsing-with-the-hosts-file

http://h30499.www3.hp.com/t5/System-Administration/large-etc-hosts-file-performance-issues/td-p/4996840#.U1wHgvmSzIY

-------------------------
http://superuser.com/questions/744219/interpretation-of-the-unix-command-ip-address

eth-man: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff
    inet 192.168.6.4/24 brd 192.168.6.255 scope global eth-man
       valid_lft forever preferred_lft forever
    inet6 xxxx::xxxx:xxxx:xxxx:xxxx/64 scope link 
       valid_lft forever preferred_lft forever

-----------------------------