Layer 7: Application Layer Communication of whatever you wish Application Can use whatever transport(s)is convenient Transport Freely structured Link E.g Physical Skype, SMTP(email) Http (wEb), Halo Bit TorrentLayer 7: Application Layer 7 4 3 2 1 Communication of whatever you wish Can use whatever transport(s) is convenient Freely structured E.g.: Skype, SMTP(email), HTTP (Web), Halo, BitTorrent 19 Application Transport (Inter)Network Link Physical