Describes network cable faults in ADSL troubleshooting.

The instance explains network cable faults during ADSL fault handling. The configuration of ADSL Fault Handling mainly describes the similarities and differences between the network cable fault and the indicator lights of ADSL. The configuration can be completed easily, there is no difficulty. Hurry into the Wireless World.

Instance 1: network cable failure

Fault description: multiple computers share the Internet with the ADSL Fault Handling Modem through the Hub. Check the local connection. The network connection icon is normally displayed on the taskbar, and "X" is not displayed on it (in fact, the network connection icon usually has "X" when the network is disconnected "), check the network connection status and find that only data packets are sent, the received data packet is 0, and the virtual dialing fails.

Troubleshooting: first, observe the port on the Hub. Ping <Nic IP address> to return normal information. The local Nic should be normal, but other computers and Modem cannot be pinged. Second, if the port is dropped on the Hub, or even directly connected to the ADSL Fault Handling Modem, the fault persists, which eliminates the Hub port fault.

Therefore, we can determine that there is a problem with the network cable, so we checked the line to see if there was a twist or break. We did not find any exception, and then re-create the crystal head connector at both ends of the twisted pair wire. The fault is still not solved. So I calmly thought that there were four pairs of twisted pair wires, the positions 1, 2, 3, 4, 5, 6, 7, and 8 in the crystal head are white orange, orange, white green, blue, white blue, green, brown, and white Brown, actually, two pairs of cables are used.

They are arranged at the positions 1, 2, 3, and 6 of the crystal head. Because the received data packet is 0, it is suspected that there is a problem with one of the lines (white orange, orange, white green, green, in fact, it should be a pair of lines in the 3 or 6 positions as the receiving data line ), as a result, the connectors are re-created at both ends of the twisted pair wires in unconventional cabling order: the positions 1, 2, 3, 4, 5, 6, 7, and 8 in the crystal head are white orange, orange, white blue, brown, white Brown, blue, white green, and green, of course, we still need to keep 1 and 2 as a line, and 3 and 6 as a line.

Reconnect the twisted pair wires to solve the problem. In order to further prove my inference: there was a problem with the white-green and green cables. Later, I borrowed the network cable tester, and the white-green and green cables were not connected, however, this pair of lines at the 7 and 8 locations is a backup line, which does not actually work and does not affect network connections.

Fault Cause: there are 4 pairs of five types of UTP twisted pair wires. Actually, two of them are used to receive and send data, A pair of lines at the positions 1, 2, 3, and 6 are faulty, causing network communication faults, in fact, network communication will not be affected even if two pairs of lines at the 4, 5, 7, and 8 locations break.

Example 2: The indicators for ADSL troubleshooting are normal and the network is also disconnected.

Fault description: multiple computers share the Internet with the ADSL Fault Handling Modem through the Hub. The ADSL Fault Handling indicators are normal, green, and sometimes dropped. Troubleshooting: After the Modem is restarted, the system is normal. Later, a proxy server with dual NICs was built, and the computer accessed the Internet through the proxy server.

Fault Cause: there is a "10Base-T" port on the ADSL Modem, which is connected to the LAN and is actually a Hub port. Although it is a 10 MB port, the upstream bandwidth of ADSL is only several hundred Kbit/s. If the user's LAN is directly connected to the Hub through ADSL troubleshooting, and the Hub connects to the following clients, many data packets irrelevant to ADSL troubleshooting in the network will occupy the Upstream Channel of ADSL troubleshooting, ADSL troubleshooting cannot control broadcast storms in the LAN.

If the uplink transmission capability of ADSL is exceeded, data packets are loaded into the ADSL cache. If the data volume continues to increase and the cache overflows, the ADSL will be "sleep", so that only the Modem is restarted. The solution is that dedicated-line users with insufficient funds can build a proxy server with dual NICs (dual NICs must be used), which can partition the direct communication between the Modem and the LAN to avoid the above problems. If conditions permit, it is best to use a firewall or router.