Summary of ADSL Internet sharing

1. Shared Internet access

(1) network connection

If you want to add an additional computer to share the Internet with ADSL, You need to purchase two more NICs, one installed on the Internet access computer, the other is installed on the computer to be shared (hereinafter referred to as the client. We recommend that you purchase a 10/100 Mbps white adaptive Nic. It is worth mentioning that if the ADSL modem is an external Ethernet interface, there will be two NICs in the Internet access computer, one for connecting to the modem and the other for connecting to another computer. Of course, a long enough pair of wire power is indispensable. It should be noted that the twisted pair used to directly connect two computers is a cross twisted pair. That is to say, the two ends of the line have different cabling methods, namely, t568a and t568b standard, 1.

　　

 

Figure 1

It is recommended that you ask the seller to help you with the purchase of twisted pair wires, but you must tell them that they are used for direct connection between two computers. The shared Networking Mode 2 is shown in.

　　

 

Figure 2

(2) Network Configuration

After connecting the two computers as shown in figure 2, we start the computer to install the driver for the two NICs. When the NIC driver is installed and works properly, the TCP/IP network protocol is automatically added. In the future, if for some reason (such as TCP/IP ~ A. Damaged). When you need to manually add the TCP/IP protocol, you can right-click the "Network Neighbor" icon on the system desktop and select "attribute" in the pop-up shortcut menu ", open the "Network and dial-up interface" dialog box, right-click the corresponding connection item, and select "properties" from the shortcut menu to open the "Connection Properties" dialog box. In this dialog box, click "Install", select "protocol" in the displayed dialog box, and click "add, in the morning, select "TCP/IP protocol" in the "select Network Protocol" dialog box, and click "OK". When the two computers work properly, after the network connection is normal. we need to specify IP addresses for the two computers to allow them to access each other.

A. network configuration for accessing the Internet computer

On the Internet Access Computer, open the "Network and dial-up connections" dialog box as described above. Because this computer also has an ADSL connection, there should be two connection items in the dialog box, one for the ADSL connection and the other for the latter-"Local Connection ". However, when we open the "Network and dial-up connections" dialog box, we find that there are two local connections, that is, the connections between the two computers (Figure 3 ).

　　

 

Figure 3

We need to specify the IP address of the latter-"Local Connection ". However, if we open the "Network and dial-up connections" dialog box, there are two local connections-"local connection 1" and "local connection 2 ", we need to determine which is the real local connection and which is the connection for the ADSL line. There are ten simple discriminant methods, that is, disconnect the ADSL dial-up connection in the tray area in the lower right corner of the juice computing machine screen, and the connection corresponding to it will be dimmed, the remaining green connection projects are actually local connections. Right-click "Local Connection" and select "properties" from the shortcut menu to open the "Local Connection Properties" dialog box. In this dialog box, select "Internet Protocol (TCP/IP)" and click "properties" to bring up the "Internet Protocol (TCP/IP) Attribute" dialog box. In this dialog box, first check "Use the following IP Address", and then enter "192.168.0.1" in the "ip address" column ", enter "255.255.255.0" in the "subnet mask" column ". Then, select "Use the following DNS server address" and enter the DNS server address of your ISP in the "preferred DNS server" Column (if you do not know, you can call the local telecommunications board to ask), 4.

　　

 

Figure 4

After the preceding steps are completed and confirmed, go back to the system desktop, right-click the "my computer" icon, and select the "Network ID" tab in the displayed "system features" dialog box. On this tab, click "properties" to bring up the "Change ID" dialog box. Here, we need to name the computer and set the "Working Group name" (note that it is not a "Domain Name ").

B. network configuration of the Client

Enter the "Local Connection Properties" dialog box, select "Internet Protocol (TCP/IP)", and click "properties" to bring up the "Internet Protocol (TCP/IP) properties" dialog box. In this dialog box, we need to set the IP address to the same network segment as the Internet access computer, that is, 192.168.0.x (X is a natural number between 2 and ). In this example, we specify the IP address as "192.168.0.2" and the subnet mask "255.255.255.0 ". Because we use the gateway to share the Internet, that is, we use the Internet access computer as the gateway computer, so the default gateway should fill in the IP address of the Internet Access Computer "192.168.0.1 ", for the preferred DNS server, enter "192.168.0.1 ". After the preceding settings are complete and "OK", return to the system desktop. Then, set "computer name" and "Working Group name" for the client according to the "Network Configuration for accessing the Internet computer" method ". Note: The name of each computer is unique and cannot be the same, but the Working Group must use the same name. The setting is basically complete. We can check whether the name of the other computer is displayed in the "Network Neighbor" of the two computers. If yes, the network is successfully established.

(3) Internet Connection Sharing

The next step is to install a proxy server software or gateway software on the computer connected to the Internet to achieve Internet Connection Sharing. The proxy server software has more functions than the proxy server software, but it is difficult to configure. The Gateway Software has weaker functions than the proxy server software, but it is more than enough for small network sharing, the most important thing is that it is easy to configure! We recommend that you use the Gateway Software Sygate. I believe everyone is familiar with it. We will use it when sharing a 56 K modem. Its new version not only supports the sharing of broadband access methods such as ADSL, but also maintains a lightweight and easy-to-configure style, so it is particularly suitable for families, Internet cafes, or small and medium-sized offices. Sygate supports all Windows versions and software download locations www.onlinedown.net/sygate.htm. Download and install the software. It will automatically detect hardware and network configurations. The only thing you need to note is: when the system asks if you want to use and configure DHCP (automatically obtain IP addresses) services, make sure to select "no" because we have configured a fixed IP address for the two computers. After the installation is complete, restart the computer and the Sygate will automatically load. Now, the Internet access computer becomes a gateway computer. When it is connected to the Internet, another computer can access the Internet through it. After the Internet access computer performs an ADSL virtual dial-up connection to access the Internet, Sygate will detect that the Internet connection has been established and automatically starts to share the connection (figure 5 ).

　　

 

Figure 5

Now the client can access the Internet.

2. multi-host internet sharing

Multi-host sharing means that in addition to Internet access to computers, two or more computers need to share the internet. We still use the previous article "dual-host internet sharing", that is, the idea of proxy server/gateway computer. However, because the total number of computers exceeds two, we cannot directly connect them together with a network cable for mutual communication. Instead, we need the help of a collection line device (HUB or switch.

We need to configure another Nic for each computer, and then purchase a hub or switch as needed. If the total number of computers is less than 8, we recommend that you purchase eight hubs. If the number of computers is large, in addition to Internet sharing, there are other sharing demands (such as organizations and Internet cafes ), we recommend that you purchase 16 or 24 vswitches. We recommend that you purchase well-known domestic brands, which are inexpensive and provide good performance. The network type shared by multiple hosts is shown in Figure 6.

　　

 

Figure 6

We need to remind you that when using a hub or switch for networking, it uses a straight-through twisted pair wire; that is to say, both ends of the line adopt the t568b method (the twisted pair wires connected to the computer and ADSL Modem are also connected to the through line ).

After the network hardware connection is complete, start the computer to install the NIC Driver and TCP/IP protocol. If it is an Internet cafe, you also need to install IPX/SPX compatible protocol, because it is used for LAN-connected games. The addition of IPX/SPX compatible protocols is the same as that of TCP/IP, and is also in the "Network Properties" dialog box.

When configuring the IP address, we still configure the IP address of the inter-net computer as "192.168.0.1", the subnet mask as "255.255.255.0", and the DNS server address of the ISP.

The IP addresses of each client are extended, namely, "192.168.0.2, 192.168.0.3 ......", The subnet mask still uses "255.255.255.0 ". The "Gateway" "DNS server" still fills in the IP address "192.168.0.1" for accessing the Internet computer ".

The same working group name and different computer names are used for naming Internet access computers and clients. For example, a computer whose IP address is "192.168.0.1" is named "A1, and so on.

Click "Network neighbors" on each computer. If other machines are visible, the network is established successfully.

Finally, install the Gateway Software Sygate on the Internet receiver computer to make it a gateway computer. Similarly, we do not use DHCP. When the gateway computer is connected to the Internet, Sygate automatically starts connection sharing.

3. Special neighbor Networking Solution

Many people share an ADSL line in the neighborhood. Although it is "dual-host internet sharing", it has a special feature, that is, after the Internet access computer is disabled (for example, the host is not at home, or when you want to shut down the computer), another user cannot use it. However, this is not an unsolved problem. If you are using a large network interface ADSL modem, you can use the "temporary line replacement" method to solve this problem.

In Figure 2 of the preceding "dual-machine Internet sharing" networking solution, we assume that the Internet access computer is host a, and the neighbor's computer is host B. If server a is disabled, server B cannot access the Internet. However, after a slight change to the connection mode, the problem can be solved.

There are two specific ways to change the form, which is slightly different, but the essence is the same:

Solution 1:

As shown in 1, we have another backup straight-through twisted pair wire between the two machines (note that it must be straight-through twisted pair wires, that is, both ends are t568b connectors ). In this way, when server a needs to be shut down, the user of server a can take the twisted pair wires that were originally connected to the ADSL modem and plug in the standby connected twisted pair wires. Then, the user of server B is notified, and the user of server B also removes the crossover twisted pair wire and inserts it into the connected twisted pair wire. This means that the ADSL modem is directly connected to the B server.

　　

 

Figure 7

Of course, this method also has some problems. First, every time user a has to notify user B, it is very troublesome. Second, when user a notifies user B, user B may not be at home ...... So we provide the second method.

Solution 2:

Add a shard at the ADSL modem exit. The principle of this Sub-branch is similar to the telephone sub-branch, that is, one port is divided into two ports and connected in parallel. This type of shard can be bought at a company that sells network products in the Computer City. After the splitter is added, two straight-through twisted wires are pulled out, one is connected to server a, and the other is routed to user B without connection. Then, establish a networking connection in the way shown in figure 2, and finally obtain the networking diagram shown in figure 2. In this way, when host a is disabled, user A does not need to notify user B. When a user B connects to the network, he finds that the connection fails and the IP address of server a cannot be pinged. Then, he can confirm that server a is disabled. Then, the B-host user unconnects the original twisted pair wires and plug in the backup direct line to directly connect to the ADSL modem.

　　

 

Figure 8

This method solves the problems in the first method. However, it is not perfect: User B cannot accurately determine whether server a is shut down and does not use the network for a period of time. When server a is being started or shut down for a short time, user B finds that server a cannot be connected and actively connects to the ADSL Modem. In this case, server a fails to connect to ADSL again. The specific method can be determined based on your actual situation.

After taking the above steps, we have not completely solved the problem. Because B is directly connected to the ADSL modem for calling and dialing, virtual dialing software (such as enternet 300) needs to be installed and the network configuration should be adjusted a little before dialing: in the "Network Properties" dialog box, change the "ip address" and "DNS server" that have been set to "Automatic Acquisition" (or you may need to specify it as another IP address, depending on the modem brand ). These adjustments usually take less than two minutes.

If your ADSL modem adopts a USB interface or a built-in PCI type, you cannot use the "temporary line modification" method to solve the problem. Because B cannot directly contact the ADSL modem. But strictly speaking, there is no way at all. As long as the user of server a permits it, we can solve the problem by means of "remote wakeup and automatic dialing" based on "dual-machine sharing": directly wake up and shut down server a from server B, and enable machine A to automatically dial up to connect to the Internet after power-on, while machine B still accesses the Internet through the gateway computer.