Two means of communication between end-system:
Communication between end systems can be divided generally into two categories:
Client - server mode (C / S mode) that is Client / Server mode, referred to as C / S mode.
Peer mode (P2P mode) that is PeertoPeer way, referred to as P2P.
1. The client - server mode
Client (client) and server (server) refers to two application processes are involved in the communication.
Client - server approach is described in the service and relationships between processes being served.
Customers are requesting party services, server services provider.
Service requestor and the service provider must use the services provided by the core of the network.
The client software features:
After the operation is called user initiates communication to a remote server when you intend to communicate (service request). Therefore, the client must know the address of the server program.
It does not require special hardware and complex operating system.
Server Software features:
A specialized program for providing a certain service, which can handle a plurality of local or remote client requests.
The system automatically calls after the start and has been constantly running, waiting passively and accept communication requests from customers around the country. Therefore, the server does not need to know the address of the client program.
Generally require powerful hardware and advanced operating system support.
After establishing the relationship between client and server communications, two-way communication can be clients and servers can send and receive data.
2. Peer connection
Peer connection (peer-to-peer, abbreviated as P2P) means that the host does not distinguish between the two which is a communication service provider or a service requester.
As long as both hosts are running a peer to peer connection software (P2P software), they can be equal, peer to peer communication connection.
Both sides can download other shared documents already stored in the hard disk.
Peer connection characteristics:
Peer connections essence is still using client-server mode, just and every host both client connections and server.
For example, when requesting the host C D services, C is the client, D is the server. But if C and at the same time provide services to F, then C and at the same time acts as a server.
Peer connection work can support a large number of peer users (above one million) work simultaneously
