So the winter months have passed us by and we’re now (potentially) nearing the summer time. I often have to wonder if spring even exists in the UK anymore! Anyway I digress, so onto the purpose of my post…
After another quarter has passed it’s time to review our previous quarters progress on our broadband faults handling. As part of the review, we survey customers at the conclusion of their fault, looking at the key parts of the process, utilizing the result as a key indicator of our progress. More…
The purpose of this blog is to help you diagnose your broadband fault. There is a fault diagnosis flowchart to accompany this, if you wish.
I’m quite sure nearly everyone reading that will be familiar with the above phrase, most of you because it’s happened to you on occasion and you’ve needed to call your ISP’s helpdesk to find out what’s going on, and many of you because you’ve had someone on the phone to you uttering those words. Either way, our sympathies are with you.
Before we go on to do any diagnosis I should explain why home diagnostics are necessary and why we can’t just ‘push our magic button’ and make the service work again.
More…
We’re at the time of the year where historically we see more faults raised about dropping connections and poor speeds.
It’s a bit of an urban myth in the broadband community, but it is actually very true that your Christmas Tree lights can have a big impact on the quality of your broadband connection. The reason for this is because these lights will create a level of interference which can cause the quality of the signal on your broadband connection to deteriorate or even drop.
There are plenty of things that you can do to try and minimise the problems caused by additional festive interference:
-Try and position your Christmas tree as far away as possible from your broadband modem/router.
-Ensure that your modem/router is plugged directly into your BT master socket – the use of extension cables will increase interference on your line.
-Make sure that you have microfilters on all active telephone sockets in your house (not just the one that your modem/router is connected to!)
If you follow all these steps then you should significantly reduce the possibility of experiencing some festive broadband problems.
If you do experience slower speeds or disconnections over the Christmas period, and you have followed all the steps above, then there are a couple of other things that you can try before raising a fault:
- Try using a different microfilter
- Unplug all telephony devices from your telephone sockets (and turn off your Christmas Tree lights!)
- Where possible, try using a different broadband modem or router (maybe you can borrow one from a friend or work?)
These are all ways of ensuring that your hardware and internal wiring are working fine and that the interference being caused is unlikely to be down to something in your house. BT are obliged to provide a broadband service to your master socket so we will always have to ask our customers to check everything between the master socket and their computer.
When you have done these checks, you can then raise a fault with us using our Faults checker over at http://faults.plus.net
This will then ask you a series of structured questions and offers similar advice on resolving your fault. Once you’ve finished raising this, we’ll then be able to run some checks on your telephone line and then raise it with BT where required.
But I don’t want to put too much of a dampener on the holiday season! From all of us here at PlusNet, we hope you have a very merry Christmas and a prosperous New Year!
As part of our commitment to improve the customer experience, we review our internal and customer facing processes, and adapt them based on changes in the products, external processes and customer feedback. As part of the review, we survey customers at the conclusion of their fault, looking at the key parts of the process, utilizing the result as a key indicator of our progress.
Some of you may have seen the words “SNR Margin” bandied around a fair bit in the forums. Quite a few may wonder what it is people are actually talking about! The SNR (or Signal to Noise Ratio) is essentially the quality of your line versus the amount of “noise” that is present on it. If you have a high SNR on your line, this means that you have a good quality telephone line with very little noise present. Because of the way that ADSL Max works, BT will try to force the highest possible speeds against a “target” margin of 6dB. This means that you will get the highest possible speed before your SNR drops to below 6dB. If you still have a higher SNR than this and your connection speed is the maximum at 8128Kbps then you should consider yourself lucky!
The target SNR is designed for those with poorer quality telephone lines. There are a number of cases where customers experience an intermittent connection when trying to connect against the target margin of 6dB. This is often resolved by increasing the target noise margin at the exchange, meaning that your line is being forced to attain an SNR of say, 9dB or 12dB. This will increase your stability, but you will see a drop in synchronisation speeds as the line isn’t being pushed as close to its limits as it could be. Obviously some sacrifices have to be drawn and stability will always be taken over speed. That’s BTs decision and not ours! It’s a pretty sensible decision nonetheless – there’s no point having a superfast connection that you can’t use.
Sometimes though, you will see cases where someone has had a fault on their line that has caused an increase in a customer’s SNR margin. This is often done as part of BT Wholesale’s diagnostic process or due to the actions of their Dynamic Line Management systems. The problem arises when the fault is fixed or the condition that caused the SNR increase is no longer present – Customers are sometimes left with an artificially high SNR margin and a lower than optimal sync rate. This is when getting the target SNR back to how it was proves to be rather tricky! I’m fairly certain that BT never envisaged that Service Providers would be asking them to lower a customer’s target SNR, as it’s this sort of thing that their automated systems are built to manage. However, we’re now in the situation where we see a number of these requests and more often than not, the only way that we’re able to get them actioned is by raising a fault and escalating it to a Team Leader within BT Wholesale’s Faults team. This is obviously far from ideal.
Because of the measures required to restore the SNR target to its original value, it will often take a considerable amount of time for such a request to be actioned – This isn’t great for our customers or us and can be very frustrating at the best of times. We have to raise a fault which will then spend time bouncing between us and BT Wholesale because their systems and processes were not designed to deal with such a request. Eventually the fault will get escalated within BT however at this point the customer, us and BT Wholesale have invested a lot of time and resource for what is basically a very simple change, which BT Wholesale have the tools to make.
We’re going to be having an internal meeting here next week to discuss amongst ourselves how we can action these requests with the optimal level of efficiency, and to collate information which we can then present to BT. As far as we’re concerned, the ideal solution would be for us to have our own ability to change target noise margins, as we’re able to do for customers on our (Tiscali) LLU platform. However, BT Wholesale have a target audience in the region of >5,000,000 whereas Tiscali’s subscriber base is considerably smaller and essentially less open to abuse. It would be extremely useful though, and BT are always extremely keen to implement changes and make improvements to the Max system. I for one, would hope that this would be something that they would seriously consider. Think of the number of man hours it would save both them and us, not to mention the improved level of response time we’d be able to offer our customers.
I’ll try to post an update when I get some further news.
James
In addition to the various blog and forum posts we have dealing with speed faults and other ADSL issues I thought I’d add one to help those that may be experiencing problems with ADSL synchronisation – hopefully this will explain a few things and also dispel a few myths as well.
The ADSL signal itself is generated at the exchange, at the DSLAM (for those that want to know, this is the Digital Subscriber Line Access Multiplexer) and then transmitted down your phone line to your modem or router. As such any fault with synchronisation will be caused by something either at the exchange, something affecting the wires between the exchange and your premises, a fault in the master socket or the modem/router. There are other possibilities but they can be bracketed in with the above.
Exchange Fault
This is usually an issue with the jumpering (this is where the wires carrying the ADSL signal are connected to your phone line) though it could also be a faulty DSLAM or line card. There aren’t any tests that either the end user or ourselves can do to prove this, though sometimes we will get an error on our line test tool that would point to a fault. One of the most annoying situations I have come across is when this tool reports that the end user’s modem is in sync even though we know it is not. This can lead to extended fault resolution times due to our faults team needing to explain to the BT wholesale diagnostics team that in spite of their test tool reporting that everything is fine a no sync fault is still present.
External Wiring Fault
These can be easy to diagnose (for example if a tree has fallen on the wires) provided the break in the wiring is easy to see. If the wire is actually broken this is also usually picked up by line tests.
It gets more difficult with issues such as wires that are partially broken, i.e. when the line flexes in the wind or even worse if there is an exposed section of wire (or hole in a green box or other junction point) that is affected by moisture, especially if this is only apparent during bad weather.
Otherwise it may well be simply that the line is too long to support the service, or there are other issues – these can include underground faults (usually costly to repair), lengths of aluminium or fibre optics – in these cases it may be too expensive for BT to replace the relevant sections of line, possibly even the whole line itself. In this case BT will consider a refund for the service – a full refund, if the service has never worked since installation (this is called an early life failure, and will be dealt with in a future blog post) or a refund from the time the fault was reported, if the service was working prior to the fault.
Internal Wiring Fault
This is easy to eliminate (within reason… if it’s a fault in the master socket it will require a visit from a BT engineer to resolve) and must be before a fault can be escalated to BT simply because BT do not guarantee any internal wiring. Provided you test the connection from the master socket and unplug all other items from the line (including faxes and Sky boxes) internal wiring should be eliminated from the equation.
As testing the connection from the master socket will also remove almost all possible sources of interference from your internal circuit, if the fault is still apparent you have proved that the fault does lie within BTs realm of responsibility.
Frequently in this case BT will send out an engineer who will fit an SSFP (service specific front plate) with a built in microfilter. This fixes most issues with interference on internal wiring/equipment but does mean that you will need to plug your ADSL equipment into the master socket as all extension sockets are filtered by design by the SSFP.
Electrical Interference
This is usually an intermittent issue, frequently occurring at similar times each day. Frequent culprits are street lighting and especially (when ’tis the season) Christmas tree lights – basically any electrical equipment does create RF interference. This can, if powerful enough, break up the ADSL signal as it travels down the phone wire.
This interference – if the cause of the fault – may well be something in your own premises, though once BT ascertain that this could be the cause of the fault they will arrange a visit from an SFI (specialist faults investigation) engineer who will search for signs of interference.
The delay if this is the case can come in several flavours. It could be that the owner of the faulty equipment is reluctant to replace this, or that a request needs to be the council to work on any affected street lights, or any of a whole plethora of other reasons. I think my favourite was the farmer whose phone line was routed over an electric fence, and every time his sheep brushed the fence his broadband would drop. Either that, or the user whose broadband would drop between 12 and 2 daily, except on Sundays – this turned out to be the chippy below him cooking pies (the microwave was faulty).
Faulty Router/Modem or wiring issue
This is another fairly common issue that should be picked up by ourselves when we are informed of a fault. Ideally we would prefer that alternative hardware is tested prior to raising a fault but if not then certainly prior to arranging an engineer visit – as such we may be able to arrange for a router to be sent out to the customer to test if they have no alternative available. However we would also ask that you bear in mind you can also test your own hardware on another known working line – if the fault is still apparent with the hardware connected to a different phone line then it is likely to be a faulty modem or router.
There are other faults that can occur but I hope this has explained the reasoning behind some of the tests we request in order that we can report a fault. It is understood that a lot of these are inconvenient, given the location of the master socket in some houses and that some people may be unable to move a large desktop PC and modem up into the loft/down into the hall or wherever. We will do our best to help out in these situations, but given the costs involved (BT have a standard charge of £144 + vat that is issued if a fault is found to be with the customers’ equipment or internal wiring) we hope you appreciate the importance of, and now the reasons behind, these tests.
Ever had a random sync-speed drop that resulted in slow throughput for days?
The necessary evil of MaxDSL (otherwise known as the IP Profile) is the throughput cap that BT assign to customers’ lines. It’s designed to stop packet loss within BT Wholesale’s ADSL network and, working alongside our own Maximum Rate for your connection helps to improve end user performance by ensuring the traffic is intelligently managed from end-to-end.
The IP Profile and bRAS profile for customer lines react to fluctuations in sync-speed (the speed at which you connect with the telephone exchange). That means that if your connection speed drops – then the IP Profile limit swiftly follows suit. In turn, we then receive an update from BT which updates our own limit for customers’ throughput. The net result is a better performing line at lower sync-speeds and therefore better performance in some fault cases.
Fluctuations in sync-speed can be caused by a variety of things. Storms, for example, can result in a reduction in sync-speed and you can also affect it by plugging telephone equipment into the line without a microfilter. A line fault could also result in increased noise on the line and therefore a lower sync-speed.
The inconvenience occurs, however, when everything returns to normal. That is, everything except your IP Profile. As explained above, it doesn’t take much to trigger a decrease of your IP Profile – that all happens smoothly! But currently it can take 3-4 days of a stable sync for it to go back up and that is what BT are now changing the logic of.
From 7th August, BT Wholesale are introducing what they call “Adaptive Rate Logic”. Essentially, this means more granular management of the sync-speed to IP Profile relationship. Under “Adaptive Rate Logic”, raising the IP Profile after a sync blip will be based on the percentage increase monitored. Lines which quickly come back up to normal sync-speed will see the IP Profile lifted within just a few hours in most cases, whilst lines with a sync-speed that increases more slowly will result in a longer wait and thus proven stability of the line before the IP profile follows.
BT’s briefing to ISPs stated :-
“The current Max logic rules mean higher sync rates are required to be sustained for 3 days to invoke an upwards BRAS profile move, irrespective of the degree of line rate change.
Adaptive Max Logic will look at the percentage of the line rate increase to determine the period before an upward BRAS profile change is implemented. A small percentage increase in line rate may mean a wait of up to 5 days to change the BRAS profile, but where a larger percentage change occurs, the BRAS profile could change within a very short time (4-6 hours). These timescales are indicative and may vary depending upon the load on our systems.
This way any lines that have dropped to an artificially low line rate for any reason ( e.g..
thunderstorm) and revert to a higher line rate soon after may only need to wait a short time for the higher BRAS profile to be invoked.”
If you wish to find out what your IP Profile is then try a BT Performance Test at http://www.speedtester.bt.com
If you think you might be suffering a speed fault, have a read of James’s excellent blog post here : http://users.plus.net/QL:8831BC49
Liam Martin
PlusNet Comms Team
Due to recent weather conditions at this time BT have implemented MBORC’s ( Matters beyond our reasonable control) across various parts of the country which is currently impacting on all faults that we deal with at this time but we expect once these have resolved to be bringing our targets back to within reasonable limits.
As more and more providers move away from the fixed speeds ADSL products, onto the newer fully rate adaptive ones, so to does the number of faults increase.
To many this seems to go against the way the product should work, as it should adapt to current conditions and ensure it is operational. Whilst true, it is only the line conditions at the time of synchronisation that apply, but more importantly, the line is operating as close to its operational limits as much as possible.
Traditional fixed speed services always had cautious line limits set against them and thus had a certain amount of breathing space, but rate adaption leaves little or none.
It is no wonder there can be a large volume of intermittent faults seen from customers moving to the product. For the most part, disconnections should be expected, as the technology isn’t designed to be a fully nailed up and robust. It is after all quite often, working over very old copper cabling.
ISPs are often presented with a problem in that they can only test a connection at one particular point in time. This is often futile and it does not say anything for the line history, leaves us in a situation were no fault is found and we can only ask the customer to monitor.
Sometimes, faults can go on for weeks without any sort of fix and in rare cases, months. Over this time, we collect data from the various tests performed and either a pattern emerges, or we notice things that go on to show either way that BT need to be involved, or a simple lack of understanding on the customers part, in terms of the product or their broadband setup.
BT Wholesale are due to launch a new tool to Broadband providers as a means to help combat this problem. Known as the RRT tool, or Reactive Repair Tool, it will allow a provider to look back at the past 14 days of customer service at the following key piece of data.
In each case, it provides the minimum values, maximum values and the average seen over the 14 days. Additionally, a computerised assessment is performed of the test results which can help identify a different fault type to that originally reported or being investigated.
In all, this is a huge step forwards. It reduces the number of times data needs to be collected before a trend can be seen, to the point this may be spotted from the start. It wont assist in all cases, but will ensure that focus is applied in the right places.
Adding to this the recent improvements documented in Recent Improvements to IPStream MAX on the comms blog and with more to come, the experiance is set to get better.
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