purplefox/gist:8684718

## gistfile1.txt
Things to note
==============

No miracles:

* If you're already getting near the top end of what your ISP advertises then it's unlikely you can get any improvement.

* This only applies to ADSL, not Fibre/Cable

Improve poor connection speed due to noise from internal extension wiring
----------------------------------------------------------------------

A very common cause of slowdown in connection speed is radio frequency interference caused by telephone extensions plugged into the master socket along side your ADSL router. Fitting a microfilter won't stop this kind of interference (you should have a microfilter already installed).

Basically your telephone extension wire can act as a big aerial - picking up radio waves which interferes with the ADSL signal. Often this is due to the "ring wire" in the telephone extension cable which is not twisted - the other two wires in the extension are a twisted pair to cancel out any radio interference. But with some cheap telephone extension cable even the other two wires are often not twisted making which allows them to introduce RF interference.

Most ISPs provide adaptor rate management at the exchange - i.e. they will automatically reduce your line speed if they detect a lot of noise on the line, e.g. due to poor wiring in your house.

So first thing, to determine whether you have an issue with your extension cable, find your telephone master socket - this is the first socket that your telephone cable hits after it reaches your house.

This has a removable face plate which you can remove with two screws, when you do so you will find another telephone socket inside, this is called the test socket. If you plug your adsl router directly into that socket it will bypass any of your telephone extension cabling in your house.

So plug your modem into that, and get connected. Then go to the web management console for your router (mine is at 192.168.1.1 but it varies with make/model).

Go to your ADSL settings page, and you should see a page which shows a lot of data something like this:

Upstream line rate (kbit/s)	1019
Downstream line rate (kbit/s)	14681
Line standard	ADSL2+
Channel type Fast
Upstream SNR (dB)  	7.6
Downstream SNR (dB)  	6
Upstream line attenuation (dB)	14.3
Downstream line attenuation (dB)	28
Upstream output power (dBmV)	11.5
Downstream output power (dBmV)	0
Upstream CRC	1486
Downstream CRC	0
Upstream FEC	0
Downstream FEC	0

Line attenuation tells you how much your signal degrades between the exchange and you. A low figure means you are closer to the exchange, a high figure means you a further.  Low is good, high is bad.

SNR = Signal to noise ratio and gives you a measure of how noisy your line is. High is good, low is bad.

From your line attenuation you should be able to calculate the theoretical maximum speed of your line. There are various calculators on the web that allow you to do that, e.g. http://www.kitz.co.uk/adsl/max_speed_calc.php If you plug your attenuation in there and the theoretical line speed is significantly faster than what you're actually getting then it's likely that your ISP has put you on an 'IP profile' which limits you to a lower bandwidth.

Everyone has an IP profile which determines the max line speed that you can get. With most ISPs this is dynamically managed by the exchange and can be shifted down if there is a lot of noise on your line or if it thinks the line is unstable in some way (e.g. you reboot the server very frequently - hint always keep your router on).

If you keep your modem plugged into your master socket and wait several days to a week, often you will be automatically put up to a faster IP profile as the exchange determines your line is less noisy than before. This process is slow and it's a pain not being able to use your phone during this period, but you can also sometimes speed up the process by contacting your ISP (this depends on your ISP) and asking them to put you on an IP profile with a lower target SNR. Sometimes you will also have to contact your ISP even if you have no dodgy wiring as you may have become stuck on a lower IP profile probably due to some historical connection issues with your line.

This is what I did here http://community.talktalk.co.uk/t5/Unlimited-Broadband/Please-set-my-target-SNR-to-6db/m-p/1117550 (I started with a 4Mib/s profile, went to a 10Mib/s profile and now I am on a 14Mib/s profile)

If you get your speed up and you then plug you re-enable telephone extension, and you find your connection speed soon gets adjusted back downwards then you know for sure you have a noise problem on that wiring.

This can be resolved in a few ways:

1. Replace all your internal telephone extension wiring with cat5/5e/6 cabling. This cable is twisted pair so should not introduce any RF interference on the line. You can run both a telephone and an ethernet signal over a single cable, e.g. see http://www.bttorj45.com/
2. Replace all your internal telephone extension wiring with good quality twisted pair telephone cable - but be sure to snip/disconnect the ringer wire as it's not twisted and it's not needed anyway with modern phones.
3. Use a RF telephone extender to remove the physical connection from the extension to the master socket

I'd say 1. is probably the best solution and it also means you can relocate your modem away from the master socket (it might not be convenient in all setups to have your modem there).

After your wiring has been fixed, the exchange should automatically readjust your IP profile to the max your line can take (after some days - don't turn your router off during this period!) but as mentioned before you can sometimes become stuck, so you may have to contact your ISP again.

Other tips:

* Keep the cable between the master socket and the modem as short as possible - many modem cables are not twisted so can pick up RF interence too. You can buy good quality twisted pair modem cables, or you can just wrap your existing cable in tin foil (which is what I did - I think it works).

Going through this process I have gone from a 3.2 Mib/s speed with 55 ms latency to 13Mib/s connection with 18ms latency.

Reducing latency (ping time)
----------------------------

By default, most ISPs (?) put you on an "interleaved" profile (you can see this in your ADSL settings). This is an error correction profile which is useful if you have a lot of erros due to noise on your connection. The down-side to it is it introduces extra latency on your connection.

If you have low errors on your connection, you can ask your ISP for your connection to be changed to "fast_path". This will dramatically reduce your latency (mine was halved). Good for gaming and other uses where low latency is useful.
	Things to note
	==============

	No miracles:

	* If you're already getting near the top end of what your ISP advertises then it's unlikely you can get any improvement.

	* This only applies to ADSL, not Fibre/Cable

	Improve poor connection speed due to noise from internal extension wiring
	----------------------------------------------------------------------

	A very common cause of slowdown in connection speed is radio frequency interference caused by telephone extensions plugged into the master socket along side your ADSL router. Fitting a microfilter won't stop this kind of interference (you should have a microfilter already installed).

	Basically your telephone extension wire can act as a big aerial - picking up radio waves which interferes with the ADSL signal. Often this is due to the "ring wire" in the telephone extension cable which is not twisted - the other two wires in the extension are a twisted pair to cancel out any radio interference. But with some cheap telephone extension cable even the other two wires are often not twisted making which allows them to introduce RF interference.

	Most ISPs provide adaptor rate management at the exchange - i.e. they will automatically reduce your line speed if they detect a lot of noise on the line, e.g. due to poor wiring in your house.

	So first thing, to determine whether you have an issue with your extension cable, find your telephone master socket - this is the first socket that your telephone cable hits after it reaches your house.

	This has a removable face plate which you can remove with two screws, when you do so you will find another telephone socket inside, this is called the test socket. If you plug your adsl router directly into that socket it will bypass any of your telephone extension cabling in your house.

	So plug your modem into that, and get connected. Then go to the web management console for your router (mine is at 192.168.1.1 but it varies with make/model).

	Go to your ADSL settings page, and you should see a page which shows a lot of data something like this:

	Upstream line rate (kbit/s) 1019
	Downstream line rate (kbit/s) 14681
	Line standard ADSL2+
	Channel type Fast
	Upstream SNR (dB) 7.6
	Downstream SNR (dB) 6
	Upstream line attenuation (dB) 14.3
	Downstream line attenuation (dB) 28
	Upstream output power (dBmV) 11.5
	Downstream output power (dBmV) 0
	Upstream CRC 1486
	Downstream CRC 0
	Upstream FEC 0
	Downstream FEC 0

	Line attenuation tells you how much your signal degrades between the exchange and you. A low figure means you are closer to the exchange, a high figure means you a further. Low is good, high is bad.

	SNR = Signal to noise ratio and gives you a measure of how noisy your line is. High is good, low is bad.

	From your line attenuation you should be able to calculate the theoretical maximum speed of your line. There are various calculators on the web that allow you to do that, e.g. http://www.kitz.co.uk/adsl/max_speed_calc.php If you plug your attenuation in there and the theoretical line speed is significantly faster than what you're actually getting then it's likely that your ISP has put you on an 'IP profile' which limits you to a lower bandwidth.

	Everyone has an IP profile which determines the max line speed that you can get. With most ISPs this is dynamically managed by the exchange and can be shifted down if there is a lot of noise on your line or if it thinks the line is unstable in some way (e.g. you reboot the server very frequently - hint always keep your router on).

	If you keep your modem plugged into your master socket and wait several days to a week, often you will be automatically put up to a faster IP profile as the exchange determines your line is less noisy than before. This process is slow and it's a pain not being able to use your phone during this period, but you can also sometimes speed up the process by contacting your ISP (this depends on your ISP) and asking them to put you on an IP profile with a lower target SNR. Sometimes you will also have to contact your ISP even if you have no dodgy wiring as you may have become stuck on a lower IP profile probably due to some historical connection issues with your line.

	This is what I did here http://community.talktalk.co.uk/t5/Unlimited-Broadband/Please-set-my-target-SNR-to-6db/m-p/1117550 (I started with a 4Mib/s profile, went to a 10Mib/s profile and now I am on a 14Mib/s profile)

	If you get your speed up and you then plug you re-enable telephone extension, and you find your connection speed soon gets adjusted back downwards then you know for sure you have a noise problem on that wiring.

	This can be resolved in a few ways:

	1. Replace all your internal telephone extension wiring with cat5/5e/6 cabling. This cable is twisted pair so should not introduce any RF interference on the line. You can run both a telephone and an ethernet signal over a single cable, e.g. see http://www.bttorj45.com/
	2. Replace all your internal telephone extension wiring with good quality twisted pair telephone cable - but be sure to snip/disconnect the ringer wire as it's not twisted and it's not needed anyway with modern phones.
	3. Use a RF telephone extender to remove the physical connection from the extension to the master socket

	I'd say 1. is probably the best solution and it also means you can relocate your modem away from the master socket (it might not be convenient in all setups to have your modem there).

	After your wiring has been fixed, the exchange should automatically readjust your IP profile to the max your line can take (after some days - don't turn your router off during this period!) but as mentioned before you can sometimes become stuck, so you may have to contact your ISP again.

	Other tips:

	* Keep the cable between the master socket and the modem as short as possible - many modem cables are not twisted so can pick up RF interence too. You can buy good quality twisted pair modem cables, or you can just wrap your existing cable in tin foil (which is what I did - I think it works).

	Going through this process I have gone from a 3.2 Mib/s speed with 55 ms latency to 13Mib/s connection with 18ms latency.

	Reducing latency (ping time)
	----------------------------

	By default, most ISPs (?) put you on an "interleaved" profile (you can see this in your ADSL settings). This is an error correction profile which is useful if you have a lot of erros due to noise on your connection. The down-side to it is it introduces extra latency on your connection.

	If you have low errors on your connection, you can ask your ISP for your connection to be changed to "fast_path". This will dramatically reduce your latency (mine was halved). Good for gaming and other uses where low latency is useful.