Advantages of VSAT
What is VSAT?
VSAT means Very Small Aperture Terminal, and it has three main
components– the satellite, a central hub with a big antenna dish, and a
number of nodes made up of smaller dish antenna at various geographical
locations that form a network through the satellite. All the nodes
communicate with the central hub by using the satellite as the medium
for communications. If an additional network such as internet
connectivity needs to be integrated with the VSAT network, it can be
done at a Network Operations Center located at the central hub, so the
multiple nodes in different locations can also have access to the
Advantages of VSAT Networks:
- Access in remote locations – this is the traditional strength of
VSAT. A geosynchronous satellite which floats on a fixed spot relative
to the ground can cover a third of the earth’s surface with its beam and
can provide connectivity to any area covered by the satellite beam. A
satellite can also focus on a particular high density region, and
multiple satellites can work together to provide global coverage. This
is very useful for remote locations such as rural areas, ships, deserts,
coastal regions, hills, and mountains where there is limited or no
- Internet Access – A VSAT network can carry data as well as voice and
video. VSAT can provide internet access in addition to point to point
WAN links. Broadband internet services are possible with VSAT networks.
- Rapid deployment – once the satellite is in orbit, the deployment at
the nodes or customer premises can be done in a few hours, or even
minutes if the equipment is available, with little training. The
deployment can be done in any region, as long as it is covered by the
- VPN – VSAT supports encryption of all data transmitted between two
sites or multiple sites, which make Virtual Private Networks utilization
possible. VPN on VSAT networks are commonly used for Corporate and
Government or Defense connectivity requirements.
- QoS – VSAT supports Quality of Service and Layer 2 prioritization
policies to be applied across the WAN link, enabling real time
applications to be deployed across the network.
- Mobile Access – This is another traditional strength of VSAT. For
example, TV broadcasters can broadcast from anywhere, even on the move.
Another application for Mobile Access is having internet access while on
- Bandwidth Allocation – With VSAT, it is possible to allocate or
restrict bandwidth based on individual applications. – This is very
useful for business communications, ensuring that critical business
applications always have a certain dedicated bandwidth across the VSAT
- Scalability – VSAT networks can be easily and cost effectively
scaled to accommodate multiple locations across the globe. VSAT can
accommodate as many as hundreds or thousands of remote sites on a single
- Standards based – VSAT networks are standards based and support
Internet Protocol and its variants through a protocol called Internet
Protocol over Satellite (IPoS). The developments are standards based,
and it enables the creation of a healthy ecosystem of terminal, hub, and
supplementary equipment, resulting in new innovations where
improvements come faster.
- Reliability – VSAT is very reliable with up-times of 99.95% and
above, and have been field tested for many years now. Mission critical
applications usually use VSAT due to its unmatched reliability.
- Back-up to Terrestrial Networks – VSAT networks act very well as
back-ups to terrestrial networks such as Leased Lines, MPLS Circuits,
Broadband DSL, and Internet over Fiber due to its very high reliability.
VSAT networks are not as affected by natural calamities like
earthquakes and storms as much as terrestrial networks. VSAT is the
first choice for backup by providing auto fail-over during failure of
terrestrial network links.
- Inter-operation with Terrestrial Networks – VSAT can seamlessly mesh
with terrestrial networks. For example, Internet over Fiber can be
provided in the metro areas while VSAT can be provided in the rural
areas for the same company. Both VSAT and Fiber can inter-operate with
each other and act as a single network.
- Single Hop – VSAT only has a single hop while communications based
on terrestrial networks need multiple hops to reach the destination.
With terrestrial networks, some factors like router performance depends
on multiple service providers and may not have end to end QoS. VSAT with
only a single hop can have end to end QoS.
- Bandwidth on Demand – VSAT supports and is better suited for Bandwidth on Demand services than terrestrial networks.
- Cost per connection is independent of the location or distance –
With VSAT, the cost per node is independent on the number of nodes and
also independent of the distance between the various nodes. The costs
for terrestrial networks such as Leased Lines increase with more nodes,
and also increase with longer distance between two locations.
Limitations of VSAT Technology
Like any other technology, VSAT has its limitations as well. Rain
attenuation might affect the performance of VSAT under rainy conditions,
and VSAT latencies are still higher than their terrestrial
counterparts. Another limitation is the high initial cost needed for
building and launching satellites, higher initial cost for terminal
equipment compared to terrestrial networks, and higher recurring monthly
costs – though through the years the costs for VSAT are getting lower
Source : www.vizocomsat.com