The formats, codes and procedures that govern data transmission between computers and mobile devices. A protocol defines the packet structure of the data and the network commands. A "protocol suite" comprises several layers, and learning each layer is essential to understanding this subject (see OSI model
TCP/IP is the standard routing protocol of the Internet and most internal networks. It ensures that every message sent was received in full (see TCP/IP
). Ethernet is the physical access method that moves packets from one node to another in a local network (see Ethernet
). The Internet uses several access methods (see ATM
Conceptually Speaking TCP/IP
The following is a conceptual TCP/IP exchange:
Are you there? Yes, I am.
Are you ready to receive? Yes, I am.
Here comes the message--blah, blah, blah-- did you get it? Yes, I did.
Here comes the next part--blah, blah, blah-- did you get it? No, I didn't - resend it.
Here it comes again-- blah, blah, blah-- did you get it? Yes, I did.
There is no more. Goodbye. Goodbye.
The following communications protocols are or have been widely used:
1-2 Wi-Fi wireless
1-2 Bluetooth wireless
2 Fast Ethernet
2 Gigabit Ethernet
2 Token Ring
3 IP (TCP/IP)
3 IPX (NetWare)
4 TCP (TCP/IP)
4 UDP (TCP/IP)
4 SPX (NetWare)
4 NetBEUI (NetBIOS)
7 SMB (NetBEUI)
7 AFP (AppleTalk)
7 NCP (NetWare)
7 NFS (TCP/IP)
7 HTTP (TCP/IP)
7 FTP (TCP/IP)
7 SMTP (TCP/IP)
7 DNS (TCP/IP)