What does intranet penetration mean? 15

As we all know, intranet computers (that is, lowid) are connected to the Internet through at least one layer of gateway, and do not have their own independent IP and port (your IP seen by others is the gateway), so others cannot actively establish a connection with you, and the two intranet users will naturally not be able to connect, let alone transmit. However, when the intranet computer can actively connect to other extranet computers with independent IPs, and then communicate through the UDP protocol, because UDP is a non-persistent connection, the gateway will open a temporary port for you, so that you can accept the UDP packets returned to you by the extranet computer.

For example, if computer A and computer B are in two different LANs, and the two LANs are behind two different NAPTs, then if A and B want to connect, communicate or transmit data, they need to be connected with the help of Mizo intranet penetration technology.

For example, our commonly used remote monitoring software needs to connect two computers with the help of intranet penetration technology. However, most remote control software does not support intranet penetration, and can only be achieved with the help of port mapping.

Let's talk about how to do port mapping:

Port mapping, in fact, is often said to be a kind of NAT address translation, its function is to translate the address in the public network into a private address, the ADSL broadband router using the routing mode has a dynamic or fixed public IP, ADSL is directly connected to the hub or switch, and all computers share the Internet.

Shenzhuo intranet penetration is NAT penetration, the term of network connection, when the computer is in the local area network, the computer nodes of the external network and the internal network need to be connected and communicated.

Whether it is intranet penetration or other types of network penetration, it is a unified method to study and solve network penetration.

NAT Traversal and NAT Traversal contain detailed information about network traversal.

Cyber infiltration is a common attack method used by attackers, and it is also a comprehensive advanced attack technique, and cyber infiltration is also a research topic for security workers, which is often referred to in their mouths"Penetration test"。

Whether it's a network penetration or a penetration test, it really refers to the same thing, which is to study how to attack a large network host server group step by step.

However, from an implementation point of view, the former is a malicious act of the attacker, while the latter is a legitimate means for security workers to simulate intrusion attack tests and then find the best security protection solution.

Intranet mapping means that when the external network access reaches your router, this access is placed on a host of the internal network. For example, you have built a web server on the intranet (i.e., **). Outside access requests can only see your router, and can only reach your router, if you don't map (some are called **, some are called virtual services) to the intranet, then visitors will be inaccessible, and you will be OK as soon as you **.

Intranet penetration. If you can get a public IP, you won't need to penetrate the intranet. Because some netizens get not the public IP from the broadband service provider, but the intranet IP of the broadband service provider.

At this time, if you want to establish a service in your intranet, you must have to penetrate the intranet.

Because you provide services, you are passively waiting for someone else to connect with you. Visitors can only see, and they can only reach the service provider, not your router, so there's nothing you can do. The service provider will not access your router, because you are in his LAN, there are so many machines in his LAN, and he doesn't know who and which port he is on.

Intranet penetration, commonly known as punching, requires a middleman to help you. First of all, you take the initiative to register with the intermediary (of course, it is automatically completed by the intranet penetration software you installed in your LAN) to provide the services you want to provide, such as the default port 80 on the web. When you go to register, the data you send goes through the router (your router, the broadband provider's router) layer by layer, and there must be a send port when you send it.

Each time you pass through a layer of routers, the router changes an IP address and a port (i.e., NAT). This data finally reaches the intermediary service provider.

In this case, the intermediary service provider will remember the public IP address and sending port of your broadband service provider (note that he cannot see your router or the IP of your LAN host). At this time, when someone else accesses this **, in fact, the first access is the service published by the intermediary service provider, of course, the intermediary knows, and then transfers your request to (or directly tells the visitor) the IP plus port of the broadband service provider (this port is the sending port when you register).

The broadband service provider then forwards the request to your router, which in turn forwards the request to a host on your local area network. Of course, you don't need to do port mapping on the router. Because nat will also have such a function.

To put it simply, intranet is a kind of local area network or office network established within a company or family, so as to realize the sharing of resources between multiple computers, including equipment, data, data, etc. The external network is connected by a gateway to other network systems, and compared to the internal network, this network system is called the external network, which is often referred to as the Internet. In order for the external network to access the intranet, the internal network needs to be penetrated.

There are many intranet penetration tools, mainly open source series, and there are also third-party products, such as zero escape penetration box, NAS companion and the like.

If you are a novice, it is recommended to use a third-party product, which is easier to get started, and if you are a network expert, then use a free tool.

FRP, ngrok, peanut shells, etc. The free ones are sunny-ngrok.

It broke through the intranet restrictions of a few** and entered the outside**.

1. Intranet penetration, that is, NAT penetration, is carried out to ensure that the data macro-only packet with a specific source IP address and source port number is not shielded by the NAT device and is correctly routed to the intranet host.

2. The essence of UDP intranet penetration is to use the NAT system on the router. NAT is a translation technology that converts private (reserved) addresses into legitimate IP addresses, and it is widely used in various types of Internet access methods and various types of networks. NAT can complete the reuse of addresses, and the internal network structure can be concealed from the outside.