Load Balancer
As the name suggests, the main load balancer to take high-end technology - load balancing technology, it can use the technology for a variety of flexible allocation of computing all network requests evenly distributed to other servers, be mitigated by sound management of Internet data traffic every day the burden on a single server, and strive to reach the web visitors to enjoy the best networking experience.
Load balancer functionality
1. The load balancer has a function of providing consistent service, load balancer request is issued in the information read by the client, the header rewriting program then sends the request to the appropriate server, the server maintains the client end information. At http communication among the load balancer to provide services consistent functionality get a good play, but the means of providing the service is not very safe. However, if after the message encryption, load balancers can not read the information hidden therein.
2. When one of the nodes in the cluster service can not be successfully processed the request, the request will be sent to other nodes up, when the request is successfully sent to another node, requesting information on the original node will automatically disappear.
3. Since all client requests will go through the load balancer, the load balancer has a statistical measurement functions, use of this feature load balancer can accurately count the number of times each traffic flow as well as the various stages of the project, etc., so that the network can adjust the system performance.
Proxy Server
Proxy Server (Proxy Server) function is to proxy network users to obtain network information. Figuratively speaking, it is a transit point for network information, is an intermediate agency between personal networks and Internet service providers responsible for forwarding a legitimate network information, and forwarding control register.
Proxy server as a bridge to connect to the Internet and Intranet, and in practical applications play an extremely important role, it can be used for multiple purposes, the most basic function is to connect, in addition to including security, caching, content filtering, access control management, etc. Features. More importantly, the proxy server is an important safety feature provided by the Internet link-level gateway, which work mainly in the Open Systems Interconnection session layer (OSI) model.
Nginx
nginx is a lightweight two-in-one web server,
Nginx is a free, open-source, high-performance HTTP server and reverse proxy server; also a IMAP, POP3, SMTP proxy server ; Nginx can publish treatment site as an HTTP server, in addition Nginx as a reverse proxy load balancing to achieve.
Speaking of agents, we use a map to study
By this picture we can see the relationship between the position of the binding agent and the corresponding location and location.
Acting on the forward and reverse proxy, the Internet there are many examples, such as a man of forty buy a house, but he and the king of four do not know, by Joe Smith to buy, but he knows who's house is that it is forward proxy.
Another example is a person buy a house, but he did not know where to housing, to go and who to contact, but he knew of forty, he just give the money to Wang Si, Wang Si will be able to provide him with a house, this is the reverse proxy .