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Why VoIP over VDSL
is bad for business
quality telephone service with a
consequent materially adverse effect
on their trading ability. VoIP over VDSL
is a significant potential risk to UK
business.”
Lower priority
The whitepaper points out that
network usage is constantly growing,
so the problem is only likely to get
worse. At the moment, for example,
priority over the public internet is given
to streaming the explosive growth of
digital TV services, such as Amazon
Prime, NOW TV and Netflix. Other
traffic may have to take lower priority
as a result.With take-up of such
services increasing, VDSL VoIP users
should expect a deteriorating service.
So what should customers choose
instead?
Spitfire offers customers its own Voice
Approved Broadband circuits for VoIP
SIP trunks. These ensure end-to-end
call QoS, with guarantees on Latency,
Jitter and Delay, both upstream and
downstream. These guarantees are not
available on VDSL broadband services.
As one of the few ISPs and fixed line
operators to offer a SIP trunk service,
Spitfire provides a complete end-to-
end SIP service via its own IP and TDM
infrastructure.
Graham Lewis, Spitfire Director IP
Engineering and author of
The Truth
about VDSL and VoIP
, said: “At Spitfire
we discourage the use of VDSL for
voice because, whilst anecdotally many
people have found it ‘good enough’, it
offers no guarantees of voice quality
or any route to resolution should voice
quality become unacceptable. Our
reassurance of an end-to-end service
with QoS guarantees has been a key
factor in the success of Spitfire SIP
trunks for VoIP.”
The whitepaper, entitled
The Truth
about VDSL and VoIP
, examines the
issues surrounding the use of VDSL
circuits for voice over IP services.
VDSL (Very High Speed Digital
Subscriber Line) or Fibre Broadband
is widely established in the UK and is
increasingly being used by businesses
for high speed Internet access with
download speeds of up to 80Mbps.
However, a broadband circuit
optimised for Internet browsing is not
necessarily the best choice for VoIP.
No guarantees
Although call quality on VDSL
circuits may currently be acceptable,
Spitfire discourages the use of VDSL
technology for voice because it offers
no guarantees of voice quality or any
route to resolution should voice quality
become unacceptable.
Spitfire explains that to give
satisfactory voice quality, a circuit must
deliver:
n
a maximum latency of 150ms end-
to-end (mouth-to-ear);
n
packet loss of less than 1%; and
n
jitter of less than 45ms.
While these technical requirements
may be met on a VDSL service most
of the time, there is no guarantee that
they will be met all or even some of
the time.
Long lead times
Users wanting to upgrade to Ethernet
connectivity for VoIP can be faced
with deployment lead times of up to a
year for Ethernet circuits. Poor quality
voice calls in the interim could reflect
badly on a business and damage its
reputation.
Harry Bowlby, Spitfire’s Joint
Managing Director, said: “Businesses
that choose a VoIP solution without
appropriate QoS guarantees are
gambling with their future. Should
voice quality issues arise, they may
find that an acceptable solution is
unavailable or takes an unacceptable
period of time to deliver, leaving
them unable to receive a business
VoIP over VDSL could spell disaster for UK businesses, warns Spitfire in its latest whitepaper
Harry Bowlby
Joint Managing
Director
Spitfire
To download a copy
of the whitepaper
and find out about
these issues in
more detail, please
visit
.
co.uk/products/
truth-voip-fibre-
broadband
COMMUNICATIONS
Businesses that
choose a VoIP
solution without
appropriate QoS
guarantees are
gambling with
their future
