Whenever a broadband link fails there are three possibilities
- The local modem or its connections
- The DSL signal over the telephone
- The ISP you are connecting to
The modem should be able to indicate whether the DSL carrier is there or not. It does this in two ways
- A light that will be solidly lit if the carrier is there and connected. When the router is powered up, green lights at the front confirm that the router is switched on and can 'sync' with the external line, but there are no lights to show whether it has been configured properly. A blinking green light shows that a connection is being negotiated. A persistent blinking green light indicates a problem in the connection between the router and the exchange.
- Logging on the box the statues of the DSL connection should be indicated
If neither are present, check the DSL signal fit by fitting a spare modem to see if the lights on the spare are lit. If not, then the DSL carrier supplied by the telecoms company is probably missing.
If present but you can't log on to the connection check with the ISP. The modem will probably have an error log that may be able to provide some useful information to pass on to the ISP.
In order to test broadband speeds the following link can be used http://www.broadband-help.com/tools/speed-test/.
It involves a Java applet and therefore requires Java, which may not work on some systems. In addition, registration (free) is required. An alternative that will provide a snapshot is http://resources.zdnet.co.uk/speedtest/
If speed is an issue, check the downstream line attenuation, displayed in dB, on the. Internet or DSL connection status from the router (192.168.1.1) panels. Line attenuation will directly affect speed,
The exchange sends to the modem/router a value for the power it is outputting, the modem/router measures the received power and from that calculates the attenuation.
