Shulou(Shulou.com)06/01 Report--

1. The difference between TCP/UDP:

TCP is relatively safe compared with UDP, but the transmission efficiency is slow.

2. What is a static route

Static routing must be configured manually and cannot adapt to the change of network topology.

Modify once

What is dynamic routing?

The router automatically sets up its own routing table and can automatically adjust it according to the changes of the actual situation.

Dynamic routing when the link between nodes in the network fails, or when other routes are available

You can choose the best available path and continue to forward messages.

View the longest matching principle of the routing table:

Look at the subnet mask

3 、 RIP

RIPv1/2 is a dynamic route used in small networks, and rip processes are started between routers.

Periodic notification of neighbor routes to ensure real-time updates of topology changes is a rumor-based routing mechanism, that is, distance vector protocol, which chooses the path according to the number of entries.

However, because the TTL of RIP is only 15 hops, 16 hops are unreachable, which limits the size of the network.

AD=120

4 、 OSPF

OSPF can adapt to medium and large networks, is also a dynamic routing, is a link-state protocol, for each neighbor in the same area of the link-state database is the same. It is divided into multiple regions, and the structure is also a backbone-branch structure, and the non-backbone communicates through the backbone area. AD=11

5 、 BGP

It can be transmitted stably for a long time. A large number of routing entries can give many attributes to routing entries and realize the flexible control of routing entries.

Sometimes it is called "route vector". There is also automatic summarization, but it can be turned off manually, because there is a subnet mask when the BGP protocol is transmitted.

The purpose of BGP is to provide an inter-domain routing system to ensure that autonomous systems can only exchange routing information without loops.

BGP routers exchange information about the path to the destination network.

BGP is a policy-based routing protocol. BGP does not consider speed in determining the best path, but allows AS to control the transmission of data flow according to a variety of BGP attributes.

6. Floating routing

Principle:

The lower the administrative distance of the routing table, the higher the priority. Floating routes, to give a simple example, such as changing the administrative distance priority of dynamic routes to low, and manually adding static routes to high priority. When there is a problem with the dynamic route, the original route will fail, and the router will automatically choose a static route to ensure that the network is uninterrupted and achieve redundant backup.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.