How resilient is
your lifeline?
Techno Talk
Mark Nelson
You would expect the upgrade of a vital public utility to improve the dependability of the one it
supersedes. But if you had in mind your telephone and broadband services, forget it. Unless current
policy is changed, you’ll be horribly disappointed.
B
y the time you read this
article, the appalling weather
and lengthy power cuts affecting
northern Britain in late November and
early December last year should be no
more than a memory. Troops had to be
called out after hundreds of thousands of
homes were without electricity, some for
over a week, after Storm Arwen brought
down power lines in what was called a
‘once in 30 years’ event. Many homes,
schools and other organisations were
without telephone, mobile or broadband communication too.
Nationwide isolation
This mayhem was the result of extreme
weather conditions and fortunately,
they affected only some parts of the
country. However, under the planned
replacement of the existing analogue
network, telephone and broadband
users across the whole country are
likely to suffer the same kind of isolation whenever a power cut lasting
more than an hour or two takes place,
possibly even sooner. OFCOM, the UK
telecomms regulator appears to be unconcerned, with its website blandly
advising: ‘Over the next few years, it
will become more common for phone
calls to be carried over broadband,
and this will eventually replace traditional landline call services. Whether
you have a corded or cordless landline
telephone, broadband-based call services need mains power to operate.’
‘Eventually,’ means in 2025 (only three
years away) and already many customers have had their telephone service
transferred onto broadband.
Necessary measures
The website (https://bit.ly/pe-mar22-ofc)
continues: ‘Providers must take all
necessary measures to ensure their
customers can call the emergency services during a power cut’. So, these
companies will need to put additional
protections in place as they move to
new broadband-based call technology.
Sounds reassuring? Hardly, because
OFCOM’s obligation on service providers (https://bit.ly/pe-mar22-ofc2)
8
mandates merely that providers should
have at least one solution available that
enables access to emergency services
for a minimum of one hour in the event
of a power outage in the premises. Yes,
you read that correctly: one hour. But
take-up of the ‘solution’ is optional
from the subscriber’s point of view.
Also, there has been no announcement
on whether the street cabinets, where
the optical signals are demultiplexed
into individual fibres into premises,
will have back-up batteries, and if so,
for how long these will last. Is this
taking ‘all necessary measures’?. Not
in my book.
When your phoneline is converted
to run over broadband (known as VoIP,
Voice over Internet Protocol), it includes
the supply of a new modem from your
telephone service provider, and this is
what requires back-up power. BT calls
this new system ‘Digital Voice’. You may
well have a mobile phone and yes, you
may be able to use this instead of your
landline phone in a power cut situation.
But only as long as the mobile’s battery
lasts out; then it’s as dead as a dodo until the juice is restored. Moreover, the
power cut may well affect the cellular
base station that your mobile ‘talks to’,
so you cannot rely for certain on the
mobile as your lifeline. It goes without
saying that the Internet won’t work at
your premises in a power cut either, as
it runs over the same broadband fibre
as the new telephone service.
Lies, damned lies and statistics
Of course, the harm done by a power cut depends on how long it lasts.
Anecdotal and personal experience
indicate an outage is usually either
less than 15 minutes or else six hours
or more. Statistically, the average cut
in the UK varied between 30 and 51
minutes in 2021 (it varied according
to where you lived). But this is both
meaningless and misleading. We need
to know whether this ‘average’ is in
fact the figure occurring most frequently, the central value in the list from
shortest to longest or the total of all
the values divided by the number of
values; each of these figures will differ. Nor does the number of outages
reported tell us how large a proportion of consumers would be affected,
nor the likelihood that you might be
affected. No doubt the apparent short
duration of the ‘average’ power outage
is what led OFCOM to allow telecomms
providers to avoid having to provide
back-up power supplies.
Fortunately, other people are better
informed. On 14 November last, David
Mitchell opined in The Guardian that
BT’s Digital Voice kills access to 999
in a power cut and ‘That’s not what I
call progress’.
Lives will inevitably be lost
So, will every VoIP phone subscriber
get a free battery back-up box? I cannot speak for every service provider
but apparently BT users will not. The
company did at least list home battery
packs for subscribers they had transferred to Digital Voice, but they were
chargeable and cost around £90. But
look for the ‘Cyberpower Back-up for
Digital Voice’ on the BT website now
and you will read: ‘We’re really sorry but we’ve sold out of this product
and are unable to obtain more stock.’
Unbelievable – there is no other word.
The current ill-considered policy will
undoubtedly cost lives. Few people
will realise that their digital landlines
will go down in a power cut, even
fewer than those know that their fully
charged mobile may not work either.
Pressure must now be put on OFCOM
to mandate that all landline phone
subscribers should receive a free battery back-up unit that plugs into and
supports all their existing main and
extension telephones, with a standby
time of at least 48 hours.
Users should also be warned that
mobiles and cordless phones cannot
be relied upon to work in a power cut,
explaining precisely why their mobile
may not work because their local base
station may be knocked out by the same
power failure and there’s not much
that landline and broadband users can
do about that. Complain to your MP!
Practical Electronics | March | 2022
