Norsk Telefoningeniørmøte 1992 - Telenor

Key trends in telecommunications
Alcatel strategy towards broadband
JOZEF CORNU
Introduction
In the coming years telecommunications
will make significant advances mainly in
two areas : mobile and personalised communications
on the one hand and broadband
communications on the other hand.
It is clear that the introduction of the
GSM standard is a milestone for mobile
communications. The standard is truly
future oriented and will permit the evolution
towards microcell networks such
as PCN. In addition the service is so feature
rich that a mobile subscriber will
have access to all the network facilities
available to a fixed subscriber. A mobile
terminal hence becomes just one way of
accessing a high performance network.
There is a general agreement that in the
years to come mobile communications
will continue to see strong growth.
Why do we need broadband?
There is less agreement on the evolution
of broadband communications. The
ISDN experience makes many people
believe that subscriber demand for such
services will develop relatively slowly.
In this presentation I would like to give
you some of my ideas on this question
and present to you the developments of
Alcatel in this field. Today the telecommunications
network is very inhomogeneous
from a bitrate point of view.
On Company premises, we find LAN’s
interconnecting computers at terminals at
bitrates of 10 to
100 Mbit/s.
The public network however is far from
these speeds. Digital switches are
operating at 64 kbit/s (although internally
at 2 Mbit/s). The access network consisting
of copper pairs is generally limited to
ISDN speeds (144 Kbit/s) or 2 Mbit/s on
selected pairs.
Only in transmission do we see a continuous
increase in bitrate, now reaching
2.4 Gbit/s and going up.
It is clear that with the increasing power
of PC’s, the decreasing cost of memory
and the increased use of graphics, the
bitrates passing between computers and
terminals will further increase.
So there will be a strong pressure for
increasing available bandwidth in
telecom networks due to the needs of
data transmission.
As large companies are usually spread
over multiple geographical locations,
there is a need to interconnect the LAN’s
operating on the various premises.
Solutions for such LAN interlinking exist
to-day. Their efficiency and speed is
however too low.
Ideally interconnection speeds should be
above LAN speeds in order to give the
same quality of service across interconnected
LAN’s as within a single
LAN.
The trend towards higher bitrates for data
transmission does not stop here though.
Many applications exist already for
which the appropriate speed for data
transfer among computers or between
computer and workstation goes up to tens
of Mbit/s or even beyond 100 Mbit/s.
Examples abound - just think of remote
printing of newspapers or meteorological
and seismological research. Already in
the US., the National Research and Education
Network project is aiming for the
introduction of a 1000 Mbit/s network
linking universities and research institutes
by 1996.
Further applications for which broadband
communications may bring great improvement
are in general those involving the
transmission of high resolution graphics
and images as well as motion video
transmission either for interactive or distributive
purposes. Specific examples
here are high quality images for remote
medical and technical diagnoses, image
banks, remote fingerprint checking,
desktop publishing and video transmission
for educational purposes. Multimedia
applications, which may include
the simultaneous use of sound, text,
graphics, still and motion video, are also
expected to find a wide range of applications.
We all know that high quality motion
video requires broadband bitrates. What
is often not realised, however, is that
user-friendly access to high resolution
graphics also requires broadband transmission
speeds. As long as the time to
fill a screen is not of importance, one can
transmit the picture at arbitrarily low
speed, no matter what the required
resolution is. User friendliness, however,
dictates that one should be able to fill a
screen in at most 0.5 seconds and this
brings the required bitrate immediately in
the range of 10 Mbit/s. For motion video,
dependent on the amount of compression,
we may need from below
1 Mbit/s all the way up to over
100 Mbit/s (HDTV).
The recent adventures of analogue
HDTV in Europe reinforce the tendency
to digital HDTV. This brings us back to
the idea of the RACE program: to provide
all services (voice, data and video)
on a single broadband network.
This obviously requires the introduction
of Fibre in the Loop. Before discussing
this point however I would like to
describe to you the products Alcatel is
developing for the introduction of broadband
networks.
Alcatel broadband
product range
In mid-1991 Alcatel Network Systems
announced its Alcatel 1000 Series (Table
1), a complete range of compatible building
blocks which allows to incrementally
evolve telecommunication networks to
the networks of the future.
The Alcatel 1000 Series contains the
following categories of broadband oriented
products:
- Synchronous transmission products
- Metropolitan Area Networks
- ATM based switching products
- Fibre in the Loop.
Such a family concept encompassing
both switching and transmission products
is necessary due to the similarities in
technologies and the steep increase in
software content.
Therefore from a supplier point of view it
is necessary to exploit to a maximum
synergies between products. From an
operator point of view the interest is equally
great as advantages in terms of
operations and maintenance are fairly
obvious.
Alcatel’s Synchronous Transmission
Products (Table 2)
This family covers products of both the
SDH and SONET variety and includes
add/drop multiplexers for access and
transport, a range of cross-connect systems,
fibre optic line systems and
network management systems.
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