Method of accessing hosts within a local area network from an extranet (port mapping)

The first things to do are as follows:

1. Confirm whether the router in your intranet supports port mapping function
2. If your router supports port mapping, install remote control software on your local computer
3, remote control software after installation, set up a router, enter the remote control software port and your native IP, do port mapping
4, in your native installation of the peanut shell, such as dynamic domain name software
5. After the test is successful, you open the Remote Software control terminal on the outside network, enter the dynamic domain name to access your own computer

Port mappings (Ports Mapping):
If you are a broadband access user, such as ADSL, modem or optical fiber, if you want to build a server or Web site within your company or organization, and you want users on the Internet to access your server, you will encounter port mapping issues.
Typically, routers have firewall capabilities that Internet users can only access to your router's WAN port (the ADSL phone or routed broadband extranet) without access to the internal server. To allow Internet users access to your server, make a forwarding setting on the router, which is the port mapping setting that allows Internet users to send requests to the router and forward them to the server or Web site you have established. This is the port mapping. Because the different router manufacturers have different names, some are called virtual servers, some are called NAT settings (Frequently asked questions in BitComet) port mappings.
In fact, the port mapping setup is very simple, for example, to map an intranet IP address of 192.168.0.66 Web server, just put the Web server IP address 192.168.0.66 and TCP port 80 into the router's Port mapping table is OK.
About security issues after opening port mappings:
After setting the port mapping, Internet users can bypass the router firewall access to your server by setting the mapped port, and control your host by attacking the vulnerability on your server, so it is necessary to hang a firewall on your server after opening port mapping to ensure security.

Peanut shell is a set of completely free dynamic Domain name resolution service client software. When you install and register the service, you can use this service to establish an Internet host with fixed domain names and maximum autonomy, no matter where you are, at any time, using any line. The "Peanut shell" support lines include ordinary telephone lines, ISDN, ADSL, cable television networks, twisted pair-to-home broadband networks and any other access lines that provide real IP on the Internet, regardless of whether the IP connected to it is dynamic or static.

Dynamic Domain Name

Each time the user gets a new dynamically assigned IP address on the Internet, the dynamic domain name software installed in the user's computer will send the IP address to the dynamic Domain name resolution server and update the domain name resolution database. When other people on the internet want to access the domain name, the dynamic DNS server returns the correct IP address to him. This is called Dynamic Domain name.

Because most Internet users are assigned to the Internet when the IP address is dynamic, with the traditional static domain name resolution method, users want to put their internet computer into a fixed domain name of the site, is not possible. And with the dynamic domain name, this dream can come true. Users can apply for a domain name, the use of dynamic Domain name resolution service, the domain name with their Internet-connected computer, so that you can build their own site at home or company, very convenient

Port mappings (ports Mapping/port Forwarding) are somewhat similar to service redirection, so some routers (Router) are also known as virtual Servers (Vsan). In order to describe the convenience, the following narrative is known as [port mapping]. Port mapping is used to enable access to specific port services from the Internet to internal network machines.

The implementation of port mapping can be divided into pure software and soft and hard combination. To implement port mapping software in pure software There are many, for example, MS windows9x/200/xp under the Porttunnel specifically for HTTP, FTP, SMTP Service port mapping, provides a lot of parameter settings, under the corresponding label menu adjustment. Also like the various versions of the Linux operating system itself to support port mapping, only need the network administrator to do the appropriate settings and adjustments can be achieved. And in the combination of soft and hard to achieve port mapping function, the main common in a variety of routers (provide gateway routing function).

Here is a description of how to implement port mappings in various routers (Router)

The general router has a port Mapping or virtual server setting. The user needs in the router (Router) "Management interface" in the corresponding port mapping interface, set up the corresponding need to map the port, protocol, intranet address, etc., in order to take effect. The method you set may vary depending on the brand and model of the router (Router). Port Mappings support A network protocol that has tcp/udp/both, so if you are not familiar with port mapping settings, you can choose both to support it.

To illustrate:

As an example of a router (Router), after enabling its routing capabilities, the network topology diagram is as follows:

This assumes that the router (Router) Default IP intranet address is 192.168.1.1, the intranet computer can generally be set to become 192.168.1.X (x=2~254), in the intranet on a computer to open IE, in the Address bar input http:// 192.168.1.1, enter the initial user name, password, and then you can see the Setup interface.

For the mail server to do the following settings: Enter "Port mapping", in the port filled 25, the protocol selected: TCP, IP Address: 192.168.1.x (x for the installation of the mail server computer LAN IP address), the same method set (POP3), 6080 (Webmail) Ports, and so on. The above assumes that the user intranet segment address is: 192.168.1.0. When set up, the port mapping function is implemented, and the mail destined to the router is automatically forwarded to the designated intranet host (192.168.1.x).

Similarly, if you want to set a special port, for example: 6000. In the port filled in 6000, the protocol selected: all (or depending on the circumstances selected), IP address: 192.168.1.x (x is the intranet segment address 1~254). Once set, any data destined for router 6000 will be automatically forwarded to port 6000 on host 192.168.1.x.

The above instructions are not for specific routers. Please refer to your router's instructions for details on how to make port mappings.

Method of accessing hosts within a local area network from an extranet (port mapping)