/vnd/media/agency_attachments/bGjnvN2ncYDdhj74yP9p.png)
The IT and
communications industries are full of hype, buzzwords, and jargon,
which confuse the actual users of the various services on offer.
They are
informed by various IT consultants that VSAT networks are the
answer to all their communications and computer connectivity
problems. With the reduction of leased-line prices and the improvement
in their up-times, they are now also confronted by offers from
various erstwhile e-mail/e-fax service providers. Also on the
offer are Virtual Private Networks (VPNs) for pure data networks,
and integrated voice and data communications solutions like
Voice over IP (VoIP) or Voice Over Data Private Networks (VODPN)
from various system integrators. They have a wide array of ERP
solutions to chose from, ranging in price from Rs 6-8 lakh to
a few crore.
This article
aims to give the actual users of the various services some perspectives
about inter-locational computer connectivity, and the various
alternative communications backbones available for this purpose,
in the back drop of actual needs, costs, security of their internal
databases, and technology
options.
Your
Communication Needs
- You have
multiple locations-offices, factories, godowns, warehouses-and
you need to communicate with them.
- You need
to talk with people in different company locations.
- You need
to send facsimile of various documents between company locations.
- You need
to transfer written instructions between company locations.
- You need
to update your databases, based on happenings at different
locations during a day, either as the events happen, or at
pre-determined intervals.
- You may
need to confer with more than one person at a time with people
situated at different locations, either over telephone or
computer.
These are
some of the normal requirements of any business. Your business
communication needs may cover all or some of the above requirements.
Present Modes of Communication
- You are
currently using the Plain Old Telephone System (POTS) or the
Public Switched Telephone Network (PSTN) through local, STD
or ISD calls for telephony and fax messaging.
- You are
on e-mail through which you have text communications with
your company locations and business partners.
- You are
beginning to computerize your activity and have already built-up
LANs connecting all computers in one location.
- You have
also built-up your computer applications through some Relational
Data Base Management Systems (RDBMS) like Ingress, Sybase,
Oracle, etc.
You are
now ready to connect computers or LANs in different locations.
- Some
of you have tried to do this through e-mail.
- Some
of you have tried dial-up communications like PSTN, ISDN,
or I-NET.
- Some
have tried the VPNs on offer.
- Some
of the larger organizations to whom costs are not a consideration,
have gone in for VSAT networks-shared-hub, DAMA, or PAMA.
The cleverer ones have kept the option of opting out of some
of these services by taking the lease option.
Despite
all these steps you find your communication bills are escalating
continuously along with the growth of your business and activity.
Depending on the inter-dependence of your company locations,
the ratio of inter-locational to total communications cost could
vary from 40 percent from
the more independent operations to 90 percent for the more dependent
operations.
Inter-locational
Communication Needs
Thus a large part of your total communications expenses is due
to your need to communicate with different company locations.
The more intense the activity, the greater this cost. The cost
generally increases as competition increases, and there is pressure
on selling prices, buying costs, and profit margins. This is
the time when you need to be in constant touch with your business
locations, but also need to keep cost in control. How can you
solve this paradox?
The more
active managers resort to restricting communications, at the
risk of losing opportunity cost benefits. They resort to text
communications through fax and e-mail. But at times of stress
mere communications of text information is not productive enough.
You need to have interactive sessions with your colleagues spread
across the country to work out ways and means of combating the
market pressures. You need to communicate more on speech or
chat sessions, which can be recorded if you have such facilities,
conference with colleagues in different locations over the telephone
networks, or by meeting at a central location.
costs more money on your present communication tools, at a time
when you need to conserve money.
Besides
the communication needs at times of pressure, what are the other
inter-locational communication needs of a normal business?
Firstly,
you need to have information on what is happening at each of
your company locations.
- What
has been the production of each of your factories?
- What
are the finished goods inventory?
- What
is the raw material position?
- What
is the sale during the day at each office?
- What
is the cash collected at each sales outlet?
- What
is the cash position in each of your banks?
- What
are the disbursement commitments of each of your company locations,
factories, offices, etc?
- These
inputs are then measured against budgets for each activity,
and variances obtained.
- Thereafter,
active management will take course correction measures to
remove/reduce the adverse variances. This is done by ascertaining
the cause of the variance, and then by discussing with the
people concerned, through text and verbal exchanges, on how
these causes of adverse variances can be removed. This calls
for more inter-locational speech and text communications.
- Apart
from the hard realities of your business, you are also required
to give them a few words of kindness and appreciation for
good work done; or advice and encouragement to overcome failure
to deliver the goods required. This communication which shows
the "human face" of your company management is what
binds your team together and generates company loyalty. In
a far-flung operation, you cannot do everything yourself.
This needs more inter-locational communications-not text,
but speech. This calls for more communications and more costs
on your present communications tools.Harnessing
Your Resources
- A machine
in one factory is under-loaded or idling, while another factory
is clamouring for a new machine of the same kind due to over-load
of existing machines.
- Service
people in one region are idling due to a lack of jobs, while
service calls remain unattended, eroding company goodwill,
in another region, due to excessive service calls.
- Sales
executives in one region have covered every inch of the territory,
while those in another have too much to cope with and large
blocks of prospects lie uncovered.
- There
are surplus funds in one bank in one part of the company.
While overdraft is being taken in another bank.
These are
just some of the problems you encounter while managing your
business. To harness all your company resources and optimize
their usage and performance, IT professionals around the world
have come up with Enterprise Resource Planning (ERP) solutions.
There are "horses for courses" and you may choose
the "horse" which best suits your own "course".
Whatever
the size and complexity of the ERP package you choose, the common
refrain is that you are mechanising all your data records, and
once ERP is on stream, you will not keep any manual records.
The security of your data records are, therefore, of vital importance,
and it is necessary to create back-ups of all databases created,
so that in case of failure of any one of the databases, back-ups
are available.
Ways
of Implementing ERP Packages
The first
to be introduced and the most common is the central server architecture,
with a mirrored server kept in another premises anywhere in
the
network.
In this
system all events in the company are recorded in a central server.
Any one wanting any information needs to log in to this central
server, or its back-up server, in case the former is out of
service, to obtain it.
The inputs
to the server could be registering a sale, booking a works order,
registering a payment collection, registering receipt of materials,
registering issue of stores to the production area, registering
inputs into finished goods stores, to mention a few of such
multifarious input activities.Typical
outputs are the printing of an invoice, issuing of a payment
receipt, purchase orders, goods receipt notes, debtors statement,
creditors statement, finished goods statements, material variance
statements, etc.
In the distributed
production and distribution/supply scenarios, it was found that
most of the resource mobilization was regionalized. The course
correction was also dealt with at regional level. In such scenarios
it did not warrant inputting all data into a central server.
It was felt the activity could best be controlled through resource
planning in regional servers. Hence the development of the distributed
server architecture in some ERP packages.
However,
some of the data still needs to be replicated in all the regional
servers, so that we do not have the situation where we have
stock piling of materials or finished goods in one region while
another region is languishing for want of raw materials or finished
goods, or staffing.
Whatever
the type of ERP architecture, a common refrain is the need for
a 100 percent secure and private communications backbone over
which your databases can be connected. Such data- base cannot
be connected through any public or shared data or voice-data
networks. Software protection through firewalls is not entirely
safe, as there is a "water hose" for every firewall;
and a de-encryption algorithm for every encryption algorithm
created.
Distributed
server architecture puts less demand (need for bandwidth) on
the communications backbone.
Application
servers in each company location reduces the demand on the backbone
further as only data is transferred through the communications
backbone connecting the LANs at each location to the distributed
or central servers, and the applications are picked up from
the local application servers.The
Options
The options
for this is one of the three VSAT options: shared hub, DAMA,
and PAMA. The third is comparatively more secure than the other
two as the channels are permanently assigned. However, the control
rests with the service provider (SP) and security can be easily
infringed with his connivance. While SP connivance is bad for
his own business, if stakes are high, its staff can be tempted.
The second
and more cost-effective option is leased-line connectivity.
This has become particularly attractive after the reduction
in leased-line prices effective from 1 April 1999. The prices
have come down by 90 percent for the highest slabs. Leased-line
connectivity solutions do not suffer from the time lag in VSAT
connectivity which is caused by the propagation delay for the
electromagnetic waves travelling 36,000 kilometres up and 36,000
kilometres down (a total of 72,000 kilometres) and as much as
144,000 kilometres in case of shared hub networks. Thus, leased-lines
are more suitable for delay-sensitive data communication applications,
as also for speech and video communication.
n Although computer-to-computer communications are required
to be carried out instantaneously as and when an event takes
place, the total volume of such communications throughout a
day, over the private network, may not be large in all cases.
Thus only a few organizations like banks for their inter-branch
and/or ATM communications, and airlines and railways for their
ticket booking applications, can justify pure data leased-line
connectivity.
For most
commercial and administrative organizations, the volume of data
communications are considerably lower as also the frequency
of such communications. Hence, if they were to have dedicated
leased-line computer connectivity, most of the time the line
will be idling. Meanwhile, the organization will be blowing
up STD bills for their speech and fax communication requirements,
through the PSTN.
To provide
100 percent secure computer connectivity over leased-lines,
cost- effectively, attempts have been made, world-wide, to integrate
voice/fax/data over a single network.
This was
first done using voice-data multiplexers, data routers, voice
switches over digital leased-lines of fractional T1 class (64
Kbps). While, the system worked satisfactorily, it had a problem
of wasted bandwidth, as parts of the total bandwidth were pre-assigned
for voice/fax and data communications, and could not be used
by other services when the assigned service was not in use.An attempt
was made to overcome this wastage by using adaptable bandwidth
multiplexers, thinking that this would make use of the unused
bandwidth. However, this system introduced inter-channel interference.
A priority has to be assigned to voice or data communications.
If priority is accorded to data communications, an ongoing voice
call gets terminated the moment a data call is initiated, or
there is a sudden burst of data traffic. If voice is given priority,
then an on going data communication is disrupted as soon as
a voice call is initiated. The adaptable bandwidth multiplexer
has not succeeded in integrating voice and data communications
on a single network.
With the
advent of multimedia in PCs, another path has been pursued in
integrating voice and data over a single network. This is VoIP.
In this system there is no multiplexer. Instead, the voice spoken
through the multimedia PC is packetized and routed along with
the data packets to the required destination. The IP address
of the packets directs the packets to the PC for which the voice
packets are meant, in the LAN or across the WAN. The problem
with this system is that the voice packets are required to queue
with all the data packets and could arrive at the destination
computer at varying intervals, depending on the number of intervening
data packets. When the voice packets are re-assembled at the
destination multimedia PC, there is a time lag, and the speech
and its accent are distorted. Although considerable work is
going on to improve the voice quality, it is quite evident that
the speech will never be the same as toll quality telephony.
The system
requires large bandwidth leased lines (64 Kbps and multiples
thereof).
The distortion and delays of voice communications make this
system unsuitable for voice conferencing application.
What
Is the Solution?
Strangely, a system has been developed for integration of voice/fax/data,
right here, in your own country-India, West Bengal, Calcutta.
The system
was conceived when only analog lines were available in the country.
It has since been upgraded to work with both analog and digital
leased-lines. This is the Private Voice-Data Telecommunications
Network (PVDTN).
PVDTN has
had successful commercial operation over the last five years.
It already has an Indian patent of 1991, and a fresh patent
application has been filed to cover the new developments in
1998, and an application for international patent coverage,
under the Patent Co-operation Treaty (PCT), is in the process
of being lodged.What
this system does is shown in the graphical representation above.
Summarizing, it gives the following benefits to the user:
- Improves
your inter-locational communications. Fixed-cost network.
No usage charge. Unlimited inter-locational communications.
- Reduces
your telecom costs substantially and fixes it for your present
business for years to come. Eliminates STD, ISD, and local
calls between company locations.
- Reduces
time and cost of inter-locational travelling.
- Improves
information flow through and operational efficiency throughout
your company.
- Introduces
new businesses seamlessly into your Net through marginal additional
costs.
- Keeps
ready, at no extra cost, a most cost-effective, 100 percent
secure communications backbone, for use for data WAN/MANs/extended
LANs; or for setting up your company''s ERP/EIS systems.
- Facilitates
meetings on the PVDTN through voice or voice-data conferencing,
helping in faster decision making.
- Capital
cost of setting up a PVDTN may be recovered within a few years
from the direct savings in telecom costs.
- Helps
you to withdraw all restrictions on inter-locational communications.
- Helps
you to solve the paradox of the need for more communications
at a time when costs have to be kept under control. There
are no additional costs for increased communications.
The Bandwidth
Equation
Communication and computer professionals love high bandwidth.
But bandwidth has a cost. Table I shows the cost of a leased-line
greater than 500 kilometres for different bandwidths. Table
II shows the quantum of data that can be transferred for different
effective line speeds, for different time intervals.
From these
you will observe, that most companies can manage with 9.6 Kbps
links, for efficiently designed ERP or EIS. Some may need higher
bandwidth links (64 Kbps or multiples thereof).
Higher bandwidths are available at higher prices. But these
are required only if you need to have video communications.
But how many of you, and how often, need them in the form of
a videoconference to justify the higher prices for your private
communications backbone? If the requirement is few and far between,
you can always use the public communications backbones meant
for this purpose. And restrict yourselves to lower bandwidths
at lower costs for your normal business communications in the
form of toll quality telephony, Group III fax, and inter-locational
computer connectivity, over your 100 percent secure private
communications backbone.PVDTN
vis-à-vis Emerging Technologies
PVDTN is an access network product that uses analog (9.6 Kbps)
or fractional T1 (64 Kbps or higher bandwidth) leased-lines
from the telephone authorities. These access lines get multiplexed
into E1 to E3 lines in the transport network, transported to
the other end and de-multiplexed to the individual channels
to be terminated at subscriber premises through the access network
at the other end of the line. The transport network is migrating
from the present Plesiochronous Digital Hierarchy (PDH) system
to Synchronous Digital Hierarchy (SDH) system. But whether it
be the present PDH or
the future SDH you will still get an end-to-end Private Virtual
Circuit (PVC) in analog or fractional T1 form for your PVDTN.
Thus PVDTN is totally immune to changes in transport technology
in communications networks.
The access
network is predominantly on copper cables from subscriber premises
to the nearest exchange building. From here on to the city Trunk
Outlet Station (microwave/OFC), the access network is built
up of larger bandwidth carriers, like cable PCM, digital microwave,
optical-fibre cables, which carry both public and private circuits.
The public circuits are terminated on the local or trunk automatic
exchanges, whereas the private circuits bypass these and are
multiplexed on to the transport network carriers. Hence changing
access network technologies do not affect PVDTN.
How Does
ATM Affect PVDTN?
Like PSTN, ISDN, Frame Relay-its predecessors-Asynchronous Transfer
Mode (ATM) is an access network protocol for broadband ISDN
over fibre optic end links. This is essentially a part of public
switched network technology bringing video communication/conferencing
to your homes and offices. As explained earlier, larger bandwidth
means larger prices, such as the difference between PSTN and
ISDN prices. For a long time to come, ATM connections will be
unaffordable to most of us, because of the high cost of opto-electronic
coupling equipment required to convert electronic signals emanating
from telephones, computers, video equipment into optical signals
and vice-a-versa.
Adopting ATM technology for private networks is way beyond our
reach and, therefore, does not affect PVDTN in any way. However,
should ATM networks together with the back-up high bandwidth
transport network become affordable for private networks at
any point of time, the PVDTN technology can still be used with
the larger bandwidths that accompany ATM and supporting transport
network, providing more services like video conferencing, and
higher data communication speeds (of the Mbps range) integrating
LANs at different organization locations across the WAN. However,
in this context we will draw your attention to Tables I &
II, which explain the cost and need for bandwidth.
Thus PVDTN technology can adapt to all types of emerging access
and transport network technologies.
What
Then is PVDTN?
PVDTN is a "business tool you cannot afford to be without". - A machine