Follow Us:

Local Links

Web Banking

News / Radio



ADSL Troubleshooting


Basic ADSL service troubleshooting steps

Many apparent problems with ADSL services can be fixed by trying a few simple techniques. We recommend that you try these BEFORE calling us for assistance, as these are the first things we'll ask you to try in most cases!

1.    Power Cycle the Modem/Router (Ethernet connected modem/routers only)
Simply turn off the modem and wait 5 seconds and then turn it back on. It will normally take 30 seconds to a minute to reconnect properly.

2.    Restart your PC (Which also resets a USB modem if you have one)
While it may sound link a very simple thing to do, you'd be AMAZED at what this one step can fix!

3.     Make sure you have dial-tone on the telephone line

If your ADSL service shares your fax line, you could use the handset on the fax machine (or just pick up the line using the "hook" button or similar).

4.      Make sure that ALL of your telephones are filtered (excluding Dry Loop)
Every device that shares the telephone line with your ADSL service MUST have either a central or in-line filter installed for proper, reliable operation. Whenever you add a new phone or other device, you need to ensure that it is filtered. Don't forget to check for out-of-sight equipment like alarm system controllers.

5.    Check the modem's indicator lights
Its a good idea to familiarise yourself with the normal "working" status of the modem, and note any anomalies as they may highlight the nature of the problem. In particular, if the sync (sometime called line, or dsl) light is flashing or not lit, check the phone line connections and filtering again). If this light is out, also remove any extension leads that are used to connect your ADSL modem to the phone line and re-test.

6.     Is it only Browsing or only E-Mail that is not working?
If some services work, but others don't, the problem isn't with your ADSL service. Check for other causes, or note specific problem details before calling

CanDo I.T Support Phone: 613-354-2056
CanDo I.T Support Email:

To Create a Support Ticket Please Click Here

Please follow the basic troubleshooting guide first found below

Please click here to run an internet speed test

Why does my ADSL drop out when the phone rings?
This may happen if an ADSL filter/splitter is not connected correctly or has become faulty. Check that all phones connected to your ADSL line have filters installed correctly.
Why is my phone line noisy when I use ADSL?

This frequently happens if filters/splitters are faulty or improperly connected. Check that all telephones have line filters installed correctly.

Why do I sometimes have short periods of time
(5-20 seconds) with no throughput?
This may mean you are suffering a complete drop-out of your ADSL service - your modem has lost contact with the telephone exchange and has to re-synchronise and re-establish the connection.

How can I check my ADSL speed?
Click here to test you ADSL Speed

How can I diagnose and fix ADSL performance problems?
The Internet is not a single network - it is a complex mesh of many networks. There are many potential causes of low performance when using any Internet access service.  Here are some issues that can cause low performance


Latency is the period of time taken to move information from one location to another - it is the delay in moving a packet of data. This is commonly expressed by ADSL users as their ‘ping time’ - which is actually a measure of the latency in moving a packet from one location to another and back again - the Round Trip Time.

By way of analogy, you might think about latency as being like the time it takes to drive to a destination and return home again.
Packet Loss
Packet loss refers to the percentage of packets which, when transmitted in the network, fail to reach their destination. Packet loss, as indicated by tools such as 'ping', indicates loss in either the outbound or the return direction, but does not indicate the location or direction in which that loss occurred. It is commonly referred to as a percentage, with 0% loss meaning all packets were carried successfully.

By way of analogy, you might think of this as the likelihood that you will actually manage to drive to a destination and get home again.

NOTE: the TCP protocol uses the loss of packets as part of its rate control and adjustment mechanisms, so a small level of packet loss is normal during TCP-based data transfers.
Transfer Rate

Also called download speed or throughput, your Transfer Rate is the rate at which data is transferred over a connection. It is often expressed as a speed in KiloBITS per second or in KiloBYTES per second.

It is common to confuse these, as they can both be abbreviated to just 'K/sec', and it's important to be clear which one you are referring to at a given time.

The factors that affect download performance are varied and latency, packet loss, and transfer rate are interdependent.

These factors matter differently to different people.
Someone who plays online games may care more about latency and packet loss than about transfer rate. This is because latency affects gameplay responsiveness - it defines the delay (or ‘lag’) between instructing an in-game character to take an action, and seeing the results reflected by the game server. Naturally, packet loss also adversely affects game play.

However, transfer rate (throughput) is not always affected by high latency or even by moderate packet loss. The responsiveness of the Internet in terms of web browsing, access to email, and similar functions, may not be significantly affected by higher latency.

Does other activity on my ADSL service affect download/upload rates?

Yes, it does.

For instance, peer-to-peer file sharing can completely consume bandwidth - preventing browsing and other use. Performance may remain low even after exiting P2P software. This is because other P2P users attempt to connect to your system for some time after you have disconnected. These attempts will consume ADSL capacity and affect performance.

You should also expect that concurrent uploads will have a significant impact on download speeds - particularly with ADSL, which has less capacity for uploading than for downloading.

All data transfers send information in both directions - when you download a file, a stream of ‘ACK’ (acknowledgement) packets flow in the return direction, managing data flow and ensuring your download works properly.

Typically, ACK packets require 1/4 to 1/8th of your download transfer rate (this varies significantly). For example, if you are downloading at 512 kilobits per second on a 512/128 ADSL connection, your ACK packets may take up 64 - 128k of your upload capacity - up to 100%. If you decide to upload a file while downloading, this places more demand on your upstream capacity - slowing the ACK packets and your entire data transfer.

Because of the asymmetrical nature of ADSL, you should expect download speeds to be very seriously impacted by any file uploads you are undertaking at the same time.
Can my ADSL device get slower over time?
Unfortunately, yes - some ADSL devices may get slower over time.

ADSL works over copper telephone lines - which are imperfect transmission paths. The ADSL device determines which parts of the copper line ‘spectrum’ are usable, and confines activity to those parts. Normally there is enough ‘good’ spectrum to allow ADSL to run at its full rated speed.

Occasionally copper lines may be degraded by external factors - for example, in some areas of the Telstra copper network, line quality may be affected after rain if moisture works its way through defective insulation around copper wires.

ADSL devices compensate for these situations by confining themselves to working parts of the spectrum - reducing your throughput. However, once the problem has cleared, some ADSL devices don’t necessarily ‘spring back’ and use all available spectrum again. Because of this, it is worthwhile power-cycling your ADSL device if your performance has degraded noticeably.

Light Status for TP-LINK ADSL Modem Router:

Check the lights on the front panel of the modem router, normally you should have the following lights:
1)Power light should be solid;
· 2) ADSL light should be solid;
If ADSL light is flashing or off:
1) a)Remove the splitter, just connect the phone line directly to the modem
2) b) Contact CanDo  to check ADSL line service if it remains off.
· 3)The corresponding LAN light should be on or flashing when a computer is plugged in.
· 4)If it is a wireless modem router, the wireless signal light should also be flashing by default.
Physical Connection:

· Connect ADSL phone line to ADSL/LINE port of modem router;
· Connect a computer to one of the LAN ports (yellow) with Ethernet cable
· Plug the power adapter to the modem and switch on it.
Note: if you use a splitter to connect your phone as well, check bellow