BGP is the third party operators by means of technology, implement different operators can access an IP together, and between different operators and can reach the fastest speed access to the technology, because of the different operators (telecom, netcom, mobile has its own AS domain) to visit each other between resource will be very slow, at this time BGP room would not stand out,
BGP room to a certain extent, solved the problem of the interconnection operators resources, improve the user's access speed, with BGP protocol implementation of the effect of single IP double lines or more lines, the solution is through the BGP protocol, directly to one of the lines on other circuit IP IP mapping, when visitors browsing your website, will automatically choose according to actual situation access to the fastest speed, the optimal route, so that users of all operators can achieve the best access speed,
Compared with the traditional double double IP room BGP rooms have so several advantages:
1. Server only need to set up an IP address, the best access route is the backbone routers on the network according to the routing hop count and other technical indicators to determine, not any system resources for the server, the server of the uplink routing and downward can choose the optimal path routing, so can realize high speed single IP dual access,
2. Because the BGP protocol itself has redundancy backup, eliminate the characteristics of the loop, so when IDC service providers have multiple BGP interconnection line can realize mutual backup, routing in a route failure route will automatically switch to the other line,
3. Using the BGP protocol can also make the network has a strong extensibility IDC network can be connected with other operators, and easily implement single IP line, do all user access Internet operators soon, this is two IP two incomparable,
BGP multi-line technology:
BGP is the routing protocol between autonomous systems, its main function is to exchange with other BGP speakers network accessibility of information, a BGP speakers are the devices that any for BGP configuration, BGP use TCP as its transport protocol (port 179), it provides the reliable data transmission,
Two BGP routers links form a transport protocol, the two routers is known AS neighbors and peers, once the transport connection form, two routers exchange message with an open and confirm the connection parameters, in this step, BGP routers exchange version number, the AS number and duration of BGP logo and other information such AS the optional parameters, if there is any a parameter between peers, there will be error notification, the connection between peers not established,
If peer routers agree on these parameters, the BGP routing tables through the UPDATE message exchange, the UPDATE message contains after each system can reach the destination list (that is, the network layer information accessibility NLRI) and each routing path properties, such as routing path attribute contains the source (ORIGIN), such as information and the priority of high and low,
BGP table for each peers in the process of BGP connection is effective, if there is a routing message changed, neighbor routers use incremental updating (message) to pass this information, BGP does not require a refresh routing information, if there is no routing changes, BGP peers only exchange reserves (keepalive) message, keepalive message is sent periodically to ensure that the connection is to remain effective,
Since BGP room really good so why not have built BGP room, mainly because need the support of basic telecom operators, the current basic operators have been strictly controlled BGP broadcasts, the main distribution can be achieved in Beijing, Shanghai, guangdong, etc also have part, most provinces and cities on the mainland is still very rare, in addition this solution need IDC providers of equipment investment, as well as the basic telecom operators have the bandwidth of the purchase, also on the time period is longer, so the current domestic used this plan is limited to the stronger professional IDC service providers,
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