Basic Connectivity Troubleshooting Guide

This is a connectivity troubleshooting guide that will cover a wide range of areas in trying to assist you troubleshoot your internet connection.

This document is only meant as a broad guide to help troubleshoot any general, basic issues you may be having with your Internet connection. We have individual guides that pertain to the individual connection types, such as ADSL, EFM, Ethernet or FTTC, so this particular document is much broader guide.

For a more comprehensive and in depth troubleshooter, you should be referring to the documentation supplied by your manufacturer for your kit, your network administrator or, ultimately, your Internet service provider.

The advice contained within refers to people using a Microsoft Windows operating system.

No Connection To The Internet

You go to connect to the Internet, but your favourite web page is not showing up. What do you do?

Well, first it is important to establish where that break in communication has occurred. To get out to the outside world, your laptop or PC must first connect to a local device, typically a router, and then the router pushes your communication out to the Internet. The break could be between your machine and the router, or it could be between the router and the outside world. Establishing where this break has happened is always a good first step, and will typically give you a head start if you need to log a fault with your administrator or ISP.

If you are connecting wirelessly, there should be a small icon on your Windows desktop by the clock that indicates the status of your wireless connection (for non-Windows users, there should be a wireless application equivalent that you can refer to). If you are connecting via a wired connection, then there will be a similar icon for your connection under the Network Settings portion of your Control Panel. If you are unsure about which connection your machine is using, refer to your network administrator.

Either way, the application should indicate whether you are connected or not connected to your local device. Normally if there is a problem or you are not connected, there will be some sort of clear indication that things are not correct, either with a yellow exclamation sign or red mark.

A more techie way of establishing this connection is by using a PING command. Again these instructions refer to a Microsoft Windows setup. There will be an equivalent if you are using an alternative, but the syntax of the commands will probably be slightly different.

Open up a command prompt and use the command: ipconfig

You should get some sort of output like this:

Basic Connectivity Troubleshooting command line screen shot

The IP Address is the local IP of your machine while the Default Gateway is the local device that we want to be connected to. In this example it is connecting over the Wireless Adapter, but you may see that it is connected over the Ethernet Adapter, which just means you are using a wire. Either way, use the command: ping 192.168.0.1 (substituting the IP of your local gateway accordingly).

Basic Connectivity Troubleshooting command line screen shot

In this example, the gateway has responded happily. This means that the connection between you and your local device is working perfectly, and the most likely point of the drop of connection is between the local device and the outside world. If you did not receive any replies from your gateway, then ideally you need to repair this part of the break before proceeding. In a network environment, always contact your network administrator if you are having problems at this stage.

If you are getting a reply from your gateway but still cannot get connected to the Internet, while you have the command prompt open, try using the same command to communicate with the outside world.

Basic Connectivity Troubleshooting command line screen shot

There are a wide variety of reliable destinations to test to. In this example we have used 8.8.8.8 which is one of Google’s servers. As you can see, the PING requests have come back fine, meaning that this machine is able to PING the outside world and a working connection to the Internet is in place.

If you are able to PING to your gateway but unable PING out to the outside world, then the break in comms is most likely to be that your gateway has lost its connection and a call to your ISP is recommended. If you are able to PING your gateway and also PING the outside world, but you are still unable to browse to an Internet page and / or receive email, then this is more likely to be a local problem to your machine, and speaking to your network administrator is advised.

Depending on whether you are a home user or in a work environment, and how small or large your company is, speaking directly to your ISP might not be an option, you might have to speak to whoever manages your home / work network before going any further. So depending on your access, knowledge and management level of your setup, the following list of suggestions is always a good guideline as a bare minimum to try before logging a fault with your ISP:

  • Reboot your router / gateway
  • Reboot your machine
  • Unplug, replug and reseat any cables between your machine and your router
  • Check and record the status of the lights on your router (refer to manual)
  • Replace the ADSL micro filter (refer to our ADSL guide for more details)
  • Plug an analogue phone into your phone line and check for a dial tone

Intermittent Connection To The Internet

You may find that your connection to the outside world seems sporadic and drops regularly. The basic troubleshooting for this is much the same as troubleshooting a no connection fault – it is important to try and establish where this intermittency is occurring.

Again using the PING command, run an extended set of PINGs to your gateway to see how consistent the connection is. Using the –t suffix will mean the PING is continuous and you can leave it running until you press Ctrl C to stop it and collate the results.

Basic Connectivity Troubleshooting command line screen shot

We can see in this example that over only 31 PINGs, 29% of them were dropped. This would indicate a definite problem in communication between the machine and the gateway. If you have a wireless connection, this is quite a common problem and you should proceed to troubleshoot what would be causing wireless interference issues. If you are using a wired connection then high packet loss of PING is much less common, and you should proceed to troubleshoot what is causing the wires between you and your gateway to drop so much information. In both instances, contacting your network administrator is a good first initial step.

If you are able to PING your gateway perfectly with minimal packet loss, then you should try the same test but to the outside world i.e. run an extended PING to a reliable Internet server like 8.8.8.8.

These tests should ideally be run from the gateway with a laptop plugged into the router directly. If you run an extended PING out to the Internet and you see high packet loss or high PING response times, then you need to contact your ISP about raising this as a fault.
Sometimes you may find that your connection to the Internet just drops completely and you lose connectivity for minutes at a time, maybe even longer. Always run a quick PING test to the outside world to verify that connectivity has been lost, but in these instances it is always best to speak to your ISP.

Things to do before raising a fault with your ISP:

  • Always try giving your router a good power cycle where you leave it off for at least a couple of minutes. Routers are pieces of electrical equipment like anything else, but generally they are left on 24 hours a day, 7 days a week, sometimes for years at a time. Over a long period of time build up of junk data, components overheating, or just general wear and tear, can cause a router to start running intermittently. It may sound like a cliché but a fresh reboot and a short period of rest can do a world of good.
  • It can be difficult but try to eliminate any environmental issues that may be causing the problems. If you are using a wired connection, make sure the cables don’t have any kinks or folds in them, and make sure they are free from desks and other pieces of furniture that may be sitting on them. Reseat cable connections where possible. If you are using wireless connectivity then look at what could be causing radio or electrical interference to the signal – things as obscure as kettles and fish tanks have been known to cause problems in the past.
  • Replace the ADSL micro filter (refer to our ADSL guide for more details).
  • Try plugging an analogue phone into the line and seeing if you can detect any interference or disturbance on the phone line. If in doubt, speak to your PSTN phone provider and get them to run some tests on your line remotely. You may be able to solve the problem with them without even having to contact your ISP.

Slow Connection To The Internet

One of the most common grumbles about Internet connectivity is the speed at which it is running. Generally speaking this is controlled by forces above and beyond our control, such as availability in your area, the distance you are from your local exchange, how many other users there are in your particular area, the list goes on. However sometimes the Internet connection is definitely underperforming and you are not receiving the speeds that you are capable of or what you have been promised in the SLA with your ISP.

When raising a fault with your network administrator or your ISP, it is important to have evidence to back up your claims. When using the lower end forms of connectivity such as ADSL, using an online speed checker such as www.speedtest.net is fine. This should provide you with a clear and accurate result of what you are getting, and give you something to compare against what you should be getting. For the higher end connectivity products such as Ethernet / Leased Line type connections, your ISP should be able to run some tests on the line remotely for you on request. The best way to test the speed on these high ends lines accurately is by downloading a file from a reliable server out on the Internet – some of the online speed checkers have been known to give inaccurate results on the higher end products.

It is important to run the speed tests both from a machine behind your normal network and from the router directly. If you find that the results differ greatly, and you are receiving a good speed from your router but not from behind your network, then clearly there is something not right within your setup and you are best off contacting your network administrator. However if you run the tests from a laptop plugged directly into the back of the router and you are still getting slowness, contact your ISP and ask them to investigate.

Why is PING in uppercase in this document?

PING is sometimes referred to as an acronym standing for Packet InterNet Groper. Therefore it is common to see it written in all uppercase. However, the name PING actually comes from active sonar terminology that sends a pulse of sound and listens for the echo to detect objects underwater.