What is a routing protocol? What are the characteristics? How are they configured?

Routing protocols are divided into static routing protocols and dynamic routing protocols.

Static routing protocol is very simple, there is nothing to describe.

Dynamic routing includes:

1 and RIP protocol-routing information protocol belong to the earliest dynamic routing protocols, which have the advantages of cost saving, low resource consumption, simple configuration, low hardware requirements and less CPU and memory occupation, so they are still used in small networks. Disadvantages: slow routing calculation, slow convergence of link changes, few routing tables that can be saved, and only networks with 15 devices can be supported at most, which is only suitable for small networks.

2.OSPF protocol-open shortest path first protocol, mainly used in enterprise networks. Advantages: the technology is mature, the problems encountered can be found in the data basically, and the convergence is fast. Because of Cisco's push, many people will use it. Disadvantages: convergence speed and security are worse than that of "Islamic State".

3. "Islamic State" protocol-the protocol from intermediate system to intermediate system, mainly used for transmission network/operator network. Advantages: The algorithm is similar to OSPF, with fast convergence and high security. Disadvantages: The information about exception handling is not as rich as OSPF.

4.BGP protocol-border gateway protocol, which is used for routing transmission in the core network, is neither good nor bad, because it does not overlap with others. A simple application program, such as BGP, can be used for routing transmission between China Netcom and Telecom. If other IGP(OSPF or Islamic State) are used, the number of routes cannot be calculated, or the route calculation is very slow, so it can support the calculation and transmission of millions of routes, which requires high equipment and resources.