Which
xDSL should I use for VideoConferencing ?
ADSL.
The standard broadband used by home users is
ADSL, which is “Asymmetric” meaning that the upstream
speed is a fraction of the down speed stream. While perfectly
adequate for file downloads such as music and software, for
emails and for web-browsing it is not as well suited to real
time communications, where performance is judged by audio and
video quality. Delays, jitter and loss of lip synchronisation
is not acceptable, and so a better service is recommended, eg.
ADSL-Max or SDSL.
ADSL-Max
In some areas, ADSL-Max is starting to become
available, offering much higher downstream speeds (up to 8Mbps)
and up to 400 or 800kbps upstream. Initial adopters of these
services also gain advantage in that few other users are likely
to have subscribed and hence contention levels are currently
low (July 2006). An ASDL-Max400 connection will typically support
a 256kbps video conference whereas an ADSL-Max800 may support
384kbps with a high degree of reliability. Every site will experience
a slightly different level of service, and so we are offering
our new users a low-cost trial, with no monthly commitment,
so if contention builds over time, through additional customers
being added in your local area, you can simply stop using the
service and switch to something else. Provided there is availability
on your existing line (see availability checker), you have nothing
to lose by trying it for a month, other than one months rental.
SDSL
Videoconferencing is two-way and so the quality
of the conference will only be as good as the upstream rate
available. SDSL is better than ADSL because it is “Symmetric”
and more suited to bi-directional communication. However it
still may be contended, which means that many other organisations
can be sharing the same exchange bandwidth, and that between
the exchange and other network nodes. This means the quality
of the Video conference is only as good as what other users
are doing at the time, which is not under your control, or that
of your ISP. Reduced contention (i.e. 1:1 rather than 5:1 or
10:1) means less sharing and better chances of high performance.
Leased
Lines & IP-Vision
Short of leasing a private network which is expensive
and rarely deployed for the sole purpose of video communication,
the most affordable option is IPVision. Available in 512k, 1M
and 2M variants in many areas of the UK, Europe and USA, this
gives an organisation access to the National Backbone Network
without contention and therefore without interference from anyone
else. The bandwidth is provided over public networks hence with
widespread access but it is operated in a similar way to a private
network, where the portion you have purchased is ALL YOURS !
Having subscribed to a monthly fee, you can leave a video conference
running all day if you wish, providing a “window to your
remote office” and thereby creating a virtual office from
two dispersed workgroups.
Why
buy Broadband via VideoCentric ?
Standard ADSL and SDSL packages can be purchased
through a large number of ISPs, so why buy it through VideoCentric
? The reason is that VideoCentric’s service is different
and unique ? We have partnered with the providers of the standard
packages but added the bits that are important to real-time
voice and video communications. Unlike ordinary ISPs who provide
bandwidth primarily for file downloads and for email and web-browsing,
VideoCentric’s service is provided with videoconferencing,
streaming and voice-over-IP in mind.
As an independent
vendor of the world’s best technology, our customers satisfaction
is not only determined by the quality of goods and excellence
of service we provide, but by the performance of the communication
links between their offices and the homes of their employees.
It is in VideoCentric’s interest to guide customers towards
a quick and effective solution which not only links two sites
on IP for a video conference, but considers how ISDN-based systems
will be accessed and how 3rd and 4th parties can be invited
into a conference on an ad-hoc basis even if they are only equipped
with a simple web-cam solution, or standard mobile phone. Yes
our services already include this connectivity !
Bridging
the gap to ISDN
Most ordinary ISPs are there simply to provide
bandwidth for data-centric applications. VideoCentric can also
provide simple bandwidth, and our contended ADSL and SDSL services
are there to do just that. However, VideoCentric recognises
that for videoconferencing, most systems deployed in the world
today are connected to ISDN networks. To bridge the gap, you
need a Gateway which can transcode different speeds, different
audio and video standards and allow for dial-in as well as dial
out. To purchase a gateway can cost many 10’s of thousands
of pounds and so many of VideoCentric’s services now INCLUDE
access to a shared gateway which bridges the gap between H.320
ISDN and H.323 Video-over-IP. In future this may also include
SIP and 3G as chargeable options.
Multiparty
conferences
Video-over-IP is generally more “Ad-Hoc”
in nature than ISDN videoconferencing. A user’s requirement
to bring in a 3rd or 4th party, a home user or a mobile phone
user, is often not planned but spurious. To purchase a MultiPoint
Bridge with all its advanced features is a major investment
even for large organisations and is often out of the question
for SOHO environments, and so access to a shared and powerful
MCU bridge, is highly desirable, provided monthly costs are
reasonable. VideoCentric charges a flat fee per month which
is within the budget range of most home users, let alone businesses.
Our un-contended IP-Vision service now includes such access
as part of the package.
Availability
Checker
By providing VideoCentric a list of post codes
or phone numbers of the sites you wish to connect, we can quickly
reply with availability and pricing of our added value bandwidth
services. Depending on the equipment at the telephone exchange
serving your site and the distance between the two we will advise
as to which service can be provided, whether we need to install
a new phone line or not, and the costs and timescale's for implementation.
Either way, we look after the complete solution for you. All
we need is the post code or phone number and we’ll give
you all the options available including “break-out to
ISDN” and MultiPoint Conferencing. At the time of writing
(July 2006) this service is simply not available from anyone
else !
IP Installation & Monthly
Charges
Depending upon availability in your area (see
availability checker), VideoCentric will price all available
options, selected from:-
ADSL for home
ADSL-Max400 for small office, home office (SOHO)
ASDL-Max800 for small business
SDSL with
10:1 contention
SDSL with 5:1 contention
SDSL with 1:1 contention
IPVision-SDSL with 1:1 contention with hi-reliability
Our pricing
will include:
• Use of your existing telephone line for ADSL
• Supply of a new telephone line for SDSL
• Supply of an appropriate DSL router for ADSL or SDSL
• Options for different bandwidths available (remember
videoconferencing is only as good as the upstream speed)
• Option for ISDN gateway access (in and out) for worldwide
H.320 communication and POTS/Mobile
• Option for MultiPoint conferencing through a shared
bridge
VALUE ADDED SERVICES
Equipment
hosting (rack-space)
Customers purchasing their own networking devices
such as MCU's and Gateways need space to house them. But often space
is not enough, consider the bandwidth required specifically to operate
that equipment, the environmental conditions (air conditioning,
dust-free, fire protected, high-security), power supply security
(battery & diesel generator back up). VideoCentric can supply
you with just 1U rack space, 5U, half a rack or a full rack through
our partnership with the Thames Valley Data Centre.
Bandwidth hosting
(UK backbone)
Putting equipment on to a network is one thing, but
minimising contention, congestion and actually having enough real
time bandwidth is another. VideoCentric’s bandwidth provider
at the Thames Valley Data Centre connects directly to the National
Backbone Network and can guarantee unrivalled levels of service
through its SLA.
Click here for pricing
Education peering (Super JANET)
Thames Valley Data Centre is peered on to the UKERNA
Super JANET backbone network as used by most Universities and many
Colleges and Schools in the UK. It means that any organisation connected
with such establishments will enjoy less contention and therefore
greater performance than when attempting to access through traditional
internet routes.
Click here for pricing
Video-over-IP Theory Training
VideoCentric staff have trained end-customers, competitive
resellers, system integrators and even some of its own manufacturers
in the theory behind H.323 real time communications. As rich media
conferencing becomes more widespread through the availability of
IP bandwidth, other organisations, traditionally working in the
data or voice markets, are going to need to understand more about
H.323 gatekeeper theory and how it enables more than just IP videoconferencing.
Interfacing with Cisco Skinny Protocol (SCCP), 3G networks and other
H.324 mobile solutions as well as the Plain Old Telephony System
(POTS) we have known for the last 100 years, will become critical
to ongoing business strategy. Companies who have already taken such
theory training very seriously include Nortel, Siemens, Cisco, Avaya,
Microsoft, Mitel, Ericsson and Alcatel, and now it is the turn of
voice and data integration companies to look at how video will impact
them as real time multimedia communications takes hold at the desktop,
in the conference room and on the hand-held mobile device.
Video-Network Design Consultancy (including voice
and 3G)
There are four approaches to designing a real-time
video-enabled network:-
1) The ad-hoc, piecemeal approach,
where the network evolves without real thought or planning. This
approach is ok when connecting just two or three offices over a
public broadband network, but what about adding in web-cam users
at home, what about the implications of firewall's, bandwidth management
and priority of traffic, to avoid impact on data and voice communication
?
2) The “data-first”
approach where adding a couple of video-enabled systems to an existing
data network might seem to be quick and inexpensive and indeed for
trailing a system it is. But consider the longer term impact. Real
time communication is bandwidth intensive and bi-directional and
unlike data traffic, needs priority on a per-packet basis. A two-way
conference may still be simple and manageable where an organisation
has say, a 2Mbps link, but what happens when you want to invite
another remote employee into your conference or involve an important
customer for a brief discussion ? This is the point at which your
multiparty conference unit (MCU bridge) needs to join the call creating
a bandwidth bottleneck in need of careful management. Having this
bridge in the right location, or sharing one on the IP-Vision public
network, is a decision that needs to be made at the outset as this
will shape the topology of your video network for the future and
ultimately the efficiency of your overall company’s communication
as the boundary between data, voice and video starts to blur. Sometimes
it is better to leave the non-real-time network alone and create
an overlay video network which can link to the data network, in
other cases it is prudent to integrate them from the start.
3) The “voice-first”
approach where an organisation’s aging telephony system is
about to be replaced. Voice-over-IP is now commonplace for those
looking for “free” telephony between their sites and
employees, but the implementation of such a solution is usually
carefully considered, well planned, and regarded as “mission
critical”. Cutting over from an old telephone system to a
new one must happen seamlessly otherwise the communication of an
entire company can be put at risk with all the undesirable consequences.
However, most voice-over-IP companies have come from the world of
circuit-switched telecommunications and are not necessarily best
qualified to advice on how to provision for rich media (video, data,
voice and control) and how to ensure that the new network will interface
seamlessly with existing ISDN video, POTS telephony and new 3G,
SIP and Cisco SCCP networks. VideoCentric has partnered with experts
in this field to ensure that “voice first” can also
mean “video next”.
4) The “video first”
approach. Few organisations would consider video above data or voice
communication upon which they already depend. But those designing
a “green-field” network from scratch do have the opportunity
to consider everything. By considering video first, you provision
(a) for adequate bandwidth,
(b) for an efficient topology,
(c) for maximising the business benefits of real-time IP communication,
(d) for interfacing with legacy systems,
(e) for interoperability with evolving networks,
(f) for accessing all your remote staff, suppliers and customers
in the future, and
(g) for a budget that not only looks at the initial implementation
cost, but at ongoing maintenance and well planned evolution
(h) for reducing travel and accommodation budgets
(i) for improving business efficiency
Think about which approach your
organisation is likely to take if you do nothing. Then think about
which approach you would ideally like them to take to get things
right and be more competitive in the future. We strongly suggest
that you don’t just leave it to “chance”. Instead,
invest in some expert technical design consultancy to take a look
at how rich media integration should be deployed in your organisation
over the next 1-5 years. Initial consultation costs nothing and
from it we can obtain a full understanding of your likely needs,
which may lead on to the preparation of a detailed bespoke report
for your management team’s consideration, and probably lead
to change in the way you do business and the way you communicate
with remote sites for ever. It’s worth getting right !
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