Classification transmission mode
1. There is connected to the connections and
Transmitting data over the network can be divided into connection-oriented and connectionless-oriented type.
Connection-oriented, before transmitting data, need to connect a communication line between the host transceiver.
For no connection, do not need to connect to and disconnect, the sender can freely send data at any time, whereas the receiving end will never know that they will receive the data from where and when.
2. Circuit switching and packet switching
There are two way communication network: circuit switching and packet switching.
Circuit switching:
In circuit switching, the switch relay is mainly responsible for the data processing, the computer is first connected to the switch, and continue the communication line by the number of connections between the switch and the switch, and therefore, when data is transmitted between the computer, the need to switch target host to establish a communication circuit, the circuit will be referred to as a connection to establish a connection, then the user can communicate, know that the connection is disconnected.
Given a computer sending and receiving information monopolize the entire circuit, other computers can only wait for a chance to use this circuit send and receive data after the end of this computer processing.
Packet switching:
Let the data communication circuit is connected to the computer to be transmitted into a plurality of packets, and then sent in after a certain order.
Since the packet-switched data is subdivided, any computer can send and receive data together, so that it improves the utilization of the communication line, since the packet has been written into the sending and receiving ends in the header portion of each packet, Therefore, even if a plurality of users while providing services to the same line, can be clearly distinguished from each packet data to the destination.
3. The classification according to the number of the receiving terminal
Classified according to the number of the communication destination address and subsequent behavior, it can be divided into:
Unicast (Unitcast)
A pair of fixed telephone communication, early.
Broadcast (Broadcast)
Sending a message from a host to all other hosts connected to it. A typical example is the television, it will be sent with the television signal to a plurality of receiving non-specific objects.
Multicast (Multicast)
Similar to broadcast, but also send information to a plurality of receiving hosts, except that defines a multicast group to the host as a receiver. Typical is the conference call.
Anycast (Anycast)
Anycast is selected as a receiving end of a communication mode in a particular host. Selecting any one of a multicast communication network host best meet the conditions of the target host to send a message as the destination host. Typical is the DNS domain name server.