Single IP dual line

The common single IP dual line refers to setting an IP on the server, which is Netcom IP or Telecom IP. Setting data packets through routing equipment is a dual line technology that is realized by sending data from the Telecom network or Netcom network. This solution can also improve the access speed of Netcom users and telecom users, and solve the problem that dual IP dual line requires routing on the server. However, because the IP address is Netcom or Telecom IP, the access user will not automatically determine the best path when sending the request packet. Therefore, this solution can only be said to be a half double line technical solution and a transitional solution. This scheme is generally a compromise scheme adopted by the single line ISP service provider to the double line ISP service provider in the transition period. General small and medium-sized websites can adopt this scheme.

Dual IP dual line

The dual IP dual line implementation means that two network cards are installed on one server. Connect the telecommunications network cable and the Netcom network cable respectively, and set a Netcom IP and a telecommunications IP, so that a server has two IP addresses. You need to add Netcom or Telecom routing tables on the server to enable Netcom users and telecom users to access from different lines. Dual IP dual line has two common usage modes:

1. The administrator sets two links with different IP addresses on the website. Netcom users click Netcom IP to access the server, and telecom users click Telecom IP to access.

2. Use BIND9 (DNS server software) to return different server IPs for different IP address requests to achieve the return of Netcom's IP when Netcom users request domain names, and the return of Telecom's IP when telecom users request domain names. This is some intelligent DNS solutions proposed by IDC.

This dual IP dual line access method improves the speed of Netcom and telecom users accessing websites to a certain extent, but the disadvantage is that the dual network card connected to the server must set the routing table on the server, which increases the maintenance difficulty for ordinary users. And all data packets need to be routed on the server and then sent to different network cards. When there is a large amount of access, the server takes up a lot of resources. This scheme is relatively simple to solve the double line problem, but the disadvantage is that it is not stable enough and the maintenance is slightly complicated. This scheme is generally used for small websites or game services.

Single IP dual line implemented with BGP protocol This scheme is to directly map the IP address of one line to the IP address of the other line through BGP protocol. When users access, they automatically select the best route, so that users do not have the slow delay of passing through different ISPs.

What is BGP?

BGP (Border Gateway Protocol) protocol is mainly used for the interconnection between Internet ASs (autonomous systems). The main function of BGP is to control the propagation of routes and select the best route. Both China Netcom and China Telecom have AS numbers (autonomous system numbers), and most of the major network operators in China are interconnected with their own AS numbers through the BGP protocol. To use this scheme to realize dual lines, you need to apply for IDC's own IP address segment and AS number at CNNIC (China Internet Information Center), and then broadcast this segment of IP address to Netcom, Telecom and other network operators through the BGP protocol. After interconnection using the BGP protocol, all backbone routing devices of Netcom and Telecom will determine the best route of the IDC machine room IP segment to ensure Netcom High speed access of telecommunication users.