VoIP market is set to explode once the telecom sector opens
up and IP Telephony is legalized in April 2002. Some enterprises
have already deployed this technology and are leveraging its
benefits. by Brian Pereira
e-mail we recently received read:
upto 90% on your ISD telephone bills, call from your Internet
connected PC. Pay in Local Currency. Available all over India.
Make Worldwide PC-to-Phone calls to Landlines."
Switching: A network/technology
in which digitized information from multiple channels
is statistically multiplexed into packets and carried
as and when required.
VoIP: The enabling technology for IP Telephony and
Internet Telephony. It indicates that voice is digitized
and converted into packets and carried over IP.
IP Telephony: Telephony application using VoIP technology
over private IP network which delivers QoS.
Internet Telephony: Internet Telephony specifically
refers to dependence on the public Internet to route
calls, as opposed to IP telephony, which uses dedicated
IP networks. QoS cannot be assured over Internet. VoIP
call control Protocols: H.323 (an ITU-T standard), SGCP,
IPDC, SIP (Session Initiation Protocol)
LEC - Local Exchange Carriers IXC - International Exchange
Carriers ITSP - Internet Telephony Service Provider
FSP - Fixed Service Provider ISP - Internet Service
Provider PSTN - Public Switched Telephone Network PBX
- Private Branch Exchange CUG - Closed User Group NLD
- National Long Distance ILD - International Long Distance
message of this kind reminds us of a not-so-new way of communicating
that's about to create a maelstrom in the Telecom sector.
If technology like Voice over IP (VoIP) and applications like
Internet Telephony or IP Telephony (See Glossary) were just
alternative ways to communicate, that wouldn't be reason enough
for enterprises to embrace them. So when computer enthusiasts
started making "free" calls from their PCs to other
PCs or phones back in 1999, the corporate world watched in
interest and thought earnestly about implementing this on
their own internal networks, (imagine the cost savings on
inter-branch telephone calls). Of course, the plethora of
new applications also prompted many to experiment with various
Today, VoIP is used (legitimately) in close user groups (CUGs),
within corporate LANs/WANs. Regulations do not permit enterprises
to route IP-based calls through traditional PSTNs (See story
on page 26 : VoIP - packaged voice and more), and ISPs are
not allowed to offer Internet Telephony services. So for now
VoIP is used in a limited way. However, the VoIP market is
set to explode once the NLD/ILD space opens up and Internet
Telephony is legalized in April 2002 (See story on page 24
: VoIP set to explode as Telecom opens up).
Indian market currently has a considerable penetration for
VoIP in the Enterprise Closed User Group, with almost 70 percent
of enterprises deploying the technology on their WAN backbones,"
says Swapan Johri, General Manager, Enterprise Solutions,
HCL Comnet. "With the opening up of the NLD/ILD space,
we can expect a big surge in the VoIP and the Soft switches
(software switches) market. However, what needs equal consideration
is the fact that the supporting technologies should also provide
high QoS (Quality of Service) for voice services, as well."
Soft switches are responsible for call-control functions such
as call routing, admission control and connection control.
Because of their increased capacity and space saving feature,
soft switches are replacing old Class 5 switches on traditional
Until now, Indian enterprises have been experimenting with
all kinds of solutions in an effort to upgrade data networks
for voice. VoIP has been implemented on Frame Relay, ATM and
Ethernet networks and there have been attempts to interface
data networks with PBX systems.
generally deploy new products quickly. They have implemented
all kinds of solutionsIP-PBX, existing PBX, traditional
PBX. We see it becoming more complex for enterprises to grow
their networks as Telecommuting increases and more branches
are added to the network," says Enis Erkel, VP-Carrier
VoIP, Asia Pacific, Nortel Networks. "Most CIOs are overloaded
looking for solutions to simplify their networks and management."
But the road to VoIP hasn't been smooth.
There have been many technical (and political) barriers and
growth has been slower than expected. All along the main impediments
to growth have been government regulations, high-costs, vendor
interoperability and lack of awareness.
As of now, enterprises need to have separate networks for
data and voice communications. And those implementing VoIP
need to have a separate network for internal communication
(VoIP in CUGs) and external calls with the rest of the world
(PSTN voice). "Since interconnection (between PSTN and
data networks) isn't permitted, a dual parallel infrastructure
has to be created thereby increasing costs," says HCL
Comnet's Swapan Johri.
An industry consultant says VoIP was slow to take off here
because of restrictions such as connecting PABXs at the endpoints
as well as those on interconnection of leased lines and PSTN
leased lines and high equipment costs are also a hindrance,"
says Ketan Sanghvi, Managing Director, WANLANd Datacom (India).
"While the government has mentioned that the restrictions
relating to VoIP will be relaxed, we still don't know what
will be the nature of these relaxations."
The other reason for slow adoption of VoIP is the adaptation
of existing networks for voice.
existing networks have been predominantly built for data communications
and are being leveraged to provide voice in the same infrastructure.
The technology per se is evolving and has stabilized to a
certain extent now," says Suresh Srinivasan, GM-Enterprise
Networking Solutions, Ramco Systems.
Srinivasan adds that the bandwidth required for VoIP technology
is higher compared to VoFr (Voice over Frame Relay), and existing
network devices need to be upgraded to accommodate QoS features.
"But these technical differences are reducing as vendors
come out with products that address these problems in a very
Rajeev Mehta, Head-Business Acquisition, Tata net, agrees.
"Although we are in the business of providing VSAT services,
we found VoFR to be quite efficient, because satellite bandwidth
(for VSAT connectivity) is expensive."
Cost has been the main reason for slow adoption of VoIP in
the enterprise. While the technology offers many benefits
and useful applications, CIOs ponder if the investment in
infrastructure is really justified. Furthermore, now that
NLD/ILD costs are being slashed, does it still make sense
to send voice over data networks?
With VoIP calls (on internal networks) being virtually free,
enterprises just need to make a one-time investment in infrastructure
(to upgrade existing data networks). Connecting two locations
on the WAN would require VoIP gateways and terminals (IP phones)
at both ends of the link. Tata net for example, is offering
such connectivity at just under Rs 2 lakh (two gateways and
two IP video phones).
Jasjit Sawhney, CEO, Net4India, says Internet Telephony can
help corporates bring down costs of ILD calls by as much as
Says Ketan Sanghvi of WANLANd DATACOM (India), "For the
enterprise, there is a significant cost-savings if VoIP is
implemented between various locations within and outside the
country under current tariff rates. However, the benefits
may vary with the costs (which currently are difficult to
predict, given the potential for intensive levels of competition
between the various long-distance players). If the cost drops
substantially (which seems a little unlikely in the near future),
the benefits of VoIP may not appear that attractive."
Internet Telephony is currently deployed in more than 90 countries.
The cost-savings and applications are appreciated by enterprises
around the world, and depending on how the Telecom sector
opens up, that may soon be the case here
on average, there is a 40-50 percent differential between
the toll quality call rates and Internet telephony rates and
the same can be expected in India," says Amitabh Singhal,
Secretary, Internet Service Providers Association of India
For now, IP telephony solutions are primarily being used by
small and mid-sized offices whose voice traffic is typically
supported by myriad technologies. "It is when IP telephony
solutions scale for use in place of conventional private branch
exchanges that corporations will realize significant cost
savings in their network hardware," says Jangoo Dalal,
VP-Channels & Business Development, Network Support Services,
Apart from cost-savings, CFOs and decision makers also question
the ROI (return on investment).
Says Debashish Mitra, VoIP Program Director, TCS, "There
is a considerable ROI upon setting up a VoIP based service.
Consider this: The Capital expenditure that is required for
providing 'n' new services over traditional networks is a
couple of order higher than that required to provide equivalent
services over an IP framework. In fact, new IP-based frameworks
make it easier to create new services and then execute the
same with minimal investment and re-compiling."
KVSSS Gunneswara Rao, Director-VoIP, D-Link (India), has a
similar opinion. "The return on VoIP infrastructure environment
derives from reduced number of networks required, easy network
management, freedom from proprietary legacy switches, lower
long-distance costs, and improved IP-based services for customers
Evidently, the cost savings and ROI will be realized once
enterprises actually deploy the technology and begin to use
IP Telephony applications in business communications. The
fact that many enterprises around the world are already enjoying
the benefits and savings of this technology is reason enough
to deploy it. Just take a look at how other Indian enterprises
are using IP Telephony, and you'll speak easy about this technology.
VoIP technology does bring forth cost-savings and new applications,
IS personnel question the quality of calls and ask if it can
match that of regular PSTN calls. There are several reasons
why quality of calls suffer. For one, data networks were not
designed for voice, and latency isn't a major issue if the
packets are purely data. However, if the packets represent
video or voice, latency becomes a critical issue for transmission,
and the time for packet delivery should be an absolute minimum.
An enterprise user says that, with adequate bandwidth, the
quality of calls (on internal networks) can match that of
PSTN calls. However, there have always been QoS issues with
Internet Telephony (routing IP-based calls through the Internet.)
of Service is an issue with Internet telephony as one does
not have control over the Internet, since it is a public platform.
But with IP telephony (that is IP-based calls on internal
networks), QoS is not an issue, as one has control on the
network," says Jangoo Dalal, VP-Channels & Business
Development, Network Support Services, Cisco India. "The
issue of QoS is not specific to India but worldwide."
The problem with Internet Telephony is that sound quality
and coherence of the conversation is compromised. With Phone-to-Phone
IP calls, the loss of quality is almost unnoticeable. However,
with Phone-to-PC calls and PC-to-PC calls, the loss of quality
is noticeable, especially with slower computers and slower
Internet connection speeds.
quality of voice is affected by the Internet telephony software
used, the processor speed, the compression technique and the
level of congestion in the network," says Jasjit Sawhney,
CEO, Net4India. "Then there are issues of latency (delay
between packets), packet loss and jittervariation in
latency between packets. Jitter morphers are used to minimize
While end-users at home may tolerate latency and jitter (due
to savings in long-distance communications), corporate users
transacting business deals over the phone or speaking with
peers abroad won't be so forgiving.
So what can be done to ensure QoS? What tools and techniques
improve QoS you need adequate bandwidth, decongestion of network
and a break up of network to carry voice and data separately,"
says Net4India's Jasjit Sawhney.
Since the same network carries data as well as voice, one
encounters latency during peak periods of data transfer. While
proper bandwidth allocation is one workaround to the problem,
better voice compression codecs also play an important role.
QoS is handled at the intermediate routers that can implement
QoS protocols like MPLS, Diffserv or Intserv and COPS. Also,
use of ITU specified (G.series) codecs at the endpoints help
in increasing the quality of voice communications over a limited
bandwidth," says Debashish Mitra, VoIP Program Director,
Venkat Kedlaya, Managing Director, Convergent Communications
India, feels there will always be problems with Internet Telephony
since the Net cannot guarantee a packet delivery method. "To
minimize the problem, an ISP offering VoIP should implement
good traffic and bandwidth management techniques."
Implementing the right tools/algorithms/codecs can ensure
QoS, asserts Ketan Sanghvi, Managing Director, WANLANd Datacom
(India). "There are sophisticated voice-compression algorithms
and better call management techniques built into billing and
call management software."
Another expert opines that routers should be configured to
assign priority to voice packets and delay the passage of
data packets. "This can be done on a private network,
but it will be a challenge to do this on the Internet,"
Then there are proprietary QoS standards developed by equipment
vendors. Nortel Networks for instance has a QoS standard called
Nortel Networks Service Classes.
Ashok Danole, CEO, Automation Experts feels the most important
aspect about QoS is that it has to be implemented end-to-endright
from the source (phones or PCs), to boxes in transit (Ethernet
switches), and routers in path. "We have implemented
techniques on many sites and can guarantee that technology
has taken care of QoS issues. When vendors start interoperating,
all issues relating to QoS will be history."
Pereira can be reached at firstname.lastname@example.org