what exactly is a vsat

8/9/2019 What Exactly is a VSAT

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Abstract

VSATs support a growing market for wide-area telecommunications. The underlyingconcept between most VSat systems is to bring telecommunications services directly to the end

user without any intermediate distribution hierarchy. In many regions of the world, the potentialusers are either widely distributed or the existing telecommunications infrastructure lacks thecapacity to expand quickly to meet the demand for new users.

VSAT networks allow multimedia traffic to be brought directly to the end user, butgenerally handle only small traffic streams. Most VSAT networks are configured in one of thesetopologies:A star topology,A mesh topology and A combination of both star and mesh topologiesA unique feature of VSAT Systems broadband satellite Internet service is its dynamic transmit(Tx) power control feature that automatically increases Tx power when necessary due to weatheror atmospheric conditions.

VSAT broadband is similar to cable and DSL services for your computer. It is Internet

service through a satellite dish that is placed on your home or business. One of the greatestadvantages of VSAT broadband is that you do not need any special software, hardware ornetworks to use it. It works with nearly any email provider and uses a satellite dish that is like theones used for satellite TV. VSAT broadband offers top of the line VPN encryption for thesecurity of your personal information and data.The cost of VSAT broadband service is comparable to other types of service. It takes only 14days to get the service,In the outlink (download) direction from the hub to the VSATs continuous carriers are used, typically morethan 256k bit/s and up to 60 Mbit/s.The data transmission rate on the return link, in the direction from the VSAT to the hub, is typically from afew 100 bit/s to 512 kbit/sVSAT is a secure and reliable medium to connect geographically dispersed locations. In a

situation where other connectivity options are not feasible, VSAT offers two distant advantages:less deployment time and easy manageability. A look at how Comsat Max has created a VSATnetwork that connects remote and major locations nationwide and the advantages your companywill gain if you go the VSAT way.

A satellite network can be installed and made operational within a week since miles of cableneed not be installed. And VSATs are available in remote locations since it doesn't need theinfrastructure of a telephone exchange to be present.

The cost of VSAT services has decreased dramatically in the last few months. This is indeed a

good sign for large enterprises and smaller companies who are poised for growthVSAT Systems can guarantee extraordinarily high QoS because we control all the variables thataffect quality.VSAT Systems has answers for latency and rainfade. Again, the secret is better technology.VSAT Systems offers several broadband satellite Internet service plans including4.09Mbps/1.5Mbps. The wide range of satellite Internet plans offered are designed to help usmatch your needs to your budget.


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VSAT Customer Applications

.Broadband direct to the homeMilitary, data transferEnvironmental monitoring,


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Chapter 1

What Exactly is a VSAT?

The Very Small Aperture Terminal (VSAT) could probably be defined as a small satellite- earth

terminal intended for two way communications. The confusion comes about when we try todefine what, precisely, we mean by small. Coupled with this is a second and equally importantquestion regarding the meaning of communication. In this article, I attempt to shed light onthese questions and address how VSATs support a growing market for wide-areatelecommunications.

Fig: Satellite Internet Access via VSAT in Ghana

Definition from a physical perspective

Small is a relative term particularly in comparison to an earth terminal with a large apertureantenna (between 3 and 13 meters, depending on the frequency band, satellite and VSATrequirements). A large earth terminal is something that only a network operator would own andmanage. Most VSAT networks employ a large terminal for various functions, including network

management, access to terrestrial networks (e.g., a gateway function), and sharing of the resourceamong a number of users. The VSAT, on the other hand, would be placed on the customerpremise and operated more like a cable modem or router, requiring little in the way of localsupport. Network management and gateway functions form the core of a hub station, historicallyrequiring a major investment in the range of $500,000 to well over a million dollars. The price ofhub entry has been an impediment to VSAT expansion, but there is a hub-less market that isgrowing in importance. Inherent in the hub-style network is a star topology whereincommunications run between hub and VSAT on a single hop basis. Familiar networks of this


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type include those used by Wal-Mart and the US Postal Service. Mesh networks, where VSATconnects directly to VSAT without passing through the hub, are coming back into vogue. TheUS military employ the mesh to provide connectivity within a theatre as well as between thetheatre and a central command.

Definition from a technology perspective

The first VSATs might have been large by todays standards, but they were different as well interms of their technology. Most were designed to provide a dedicated point-to-point link (e.g., anailed up circuit) that transparently passed a symmetrical bit stream in both directions.Introduced first for the Intelsat Business Service (IBS) and later defined as Intermediate Rate(IDR) links, they can still be found in the cellular backhaul and Internet extensions as well.

True VSATs in terms of dish size appeared some 15 years ago to replace star data networkscomposed of the old multi-drop terrestrial leased lines employed in the IBM mainframeenvironment. These and other connections supported proprietary data communications protocols,and the VSATs and associated hubs were highly proprietary as well.

Getting the data over the satellite involves the familiar multiple access techniques: time divisionmultiple access (TDMA), which is the most common in the industry; frequency division multipleaccess (FDMA), best used for voice services or where a transparent link is needed; and codedivision multiple access (CDMA), now exploited for short burst transmissions with minimaldelay and improved multiple access efficiency.

Definition from an application perspective

The common theme of the VSAT user is, I need connectivity out there! They want to makephone calls, get access to the Internet, and reach into the enterprise network. What informationthey actually put through the VSAT varies as much as the basic communication mode just cited.And the platforms at the remote end likewise can reflect extraordinary circumstances. Some ofthe examples I have seen include: commercial and private jets, recreation vehicles, trailer parks,super yachts, luxury hotels on remote islands, and ranches in places where one needs to drivetwo hours to find a working telephone.

The VSAT network addresses the unique aspects of satellite communication (propagation delay,error rates and availability) and interfaces with the user side. However, there will still bechallenges in meeting user requirements. The application system will likely include a LAN withattached client computers. Depending on the special nature of the user requirement andinformation delivery mechanism, other equipment and software will likely be needed.


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Bottlenecks and their Removal

The executive session by the GVF clearly points to bottlenecks that impede a greater reliance onVSATs in vertical markets. To achieve the application benefits in a realistic manner continues tobe a challenge. Here is a summary of the bottle necks and suggestions for their removal.

Financial. The cost of VSAT hardware and software has dropped substantially and no longerrepresents the hurdle it once was. Today, potential buyers see very significant operating costs tocover satellite, hub and backhaul circuit usage. The user may today be able to afford the cost, butcannot predict what their need will look like a year later. Therefore, what we need is a system notunlike that of the disaster recovery industry. Under that scenario, the user pays a relatively lowmonthly charge and experiences an increases when usage grows. A service agreement couldallow the user to modify or terminate the arrangement under reasonable financial conditions. We

probably can no longer live in a world of satellite and teleport leases that effectively tie thecustomer to the operator for ones entire career.

Logistical. VSATs and hubs are fixed to one place. Traditionally, this required a permanentinstallation and a long operating life. The problem with this approach is that it takes a lot of timeto prepare the site and get things installed and into service. The other side of the coin is that mostof these initial charges cannot be recovered when service is terminated. What we need instead isfast deploy (and redeploy) of earth station equipment. The user and operator will have greaterflexibility and sunk costs will go down. Higher equipment cost to provide this flexibility will bedriven down as more of it is fielded (right now, the market for a portable VSAT is ten to twentytimes that of a fixed installation). Looking at the hub, transportability amounts to installation in asuitable shelter that can be placed on a flatbed truck. These are common in the cellular industryfor temporary cell sites. Transportable VSATs and hubs would be flexible and resalable.Already, eBay is offering DIRECTV and DISH network equipment and Gilat SkyStar VSATs.

Security and confidentiality. Any organization that would put its internal data over a wirelesslink will be concerned about the secure operation of the system. The technology for this, in termsof encryption and conditional access, is readily available. Also, satellite wide area networksemploy Virtual Private Network (VPN) security technology, such as IP-Sec, which protects dataand resources before information even reaches the VSAT or hub. There are still issues gettingtraditional security technology, such as IP Sec, to interface properly with the software of theVSAT. Recently, Gilat and HNS announced that they have working solutions, and othersuppliers are talking this way as well. I would therefore be confident that this particularbottleneck can be opened for any new project.

Regulatory. Restrictions on the use of transmit earth stations have given VSAT networkdevelopers a lot of headaches. In some countries, VSATs are almost impractical because oflimitations posed by the local authorities. The GVF is a leading force for change in the world,working with operators, users, governments and the ITU to facilitate the expansion of this


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technology to places where it will do the most good. I recommend a careful reading of the whitepapers and initiatives of the GVF; readers can follow up with the GVF for additional guidance.

Resources. The final bottleneck relates to directed resources needed to put VSATs into practice.These include suppliers, knowledgeable users, and the folks that will operate the network once it

is in and working. I have seen many times that people almost anywhere have learned what theyneed to know to use satellite communications and get the most from it. Much of this was gleanedin the field and during training courses Ive led for the US Telecommunications TrainingInstitute and UCLA. The keys are: (1) find people who are interested and have a basicunderstanding of the application system itself, (2) survey the suppliers and make them show youthat they can do the job, and (3) allow the time to understand what you want to accomplish, howthe project will be managed, and for proof of network performance as well as training of staff.

Bottlenecks are not what they were back in the not-so good old days. We are at a time whenVSATs are a known quantity and when many organizations believe that they can solve theirproblem. But, putting this together is still a fairly complex process. My recommendation is to

take the time to study each and every element, from all dimensions (technical, management,application and financial). I believe that the members of our industry are better prepared to helpovercome the bottle necks, and often all we need to do is ask for the help.

Overview of VSAT:The underlying concept between most VSat systems is to bring telecommunications servicesdirectly to the end user without any intermediate distribution hierarchy. Historically, traffic fromindividual users was bundled together into ever-larger groups and carried over trunk transmissionlines via terrestrial microwave systems, satellite systems, or optical fibre cables, before beingdemultiplexed into smaller traffic streams and re-distributed to the users at the far end. This isstill most economical transmission architecture for point-to-point communications when theservices are brought into areas with relatively high concentration of users. Such conditions donot always apply, however, and VSAT networks take advantage of the wide area broadcastcapabilities of GEO satellites.

In many regions of the world, the potential users are either widely distributed or the existingtelecommunications infrastructure lacks the capacity to expand quickly to meet the demand fornew users. This situation applies to most developing countries and, in evolution oftelecommunications systems. Geostationary satellites allied to microwave cellular technologieshave been used to bypass completely the traditional expansion analog telephony. One suchsolution is wire3less local loop (WLL) coupled with VSAT distribution architectutres.

VSAT networks allow multimedia traffic to be brought directly to the end user, but generallyhandle only small traffic streams. The traffic stream is usually intermittent in nature: the useraccesses the satellite in a demand assigned multiple access(DAMA) mode whenever a messageis to be sent and receives a short reply in due course. This typical point of VSAT system that isused to transmit credit card information at a store register. Information about the sale and thecustomers credit is sent to central computer facility and an authorization or denial is received in


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response.The interaction between the VSAT and the main hub earth station is completelyautomatic and transparent to the user.

Chapter 2

VSAT Configurations

Most VSAT networks are configured in one of these topologies:

y A star topology, using a central uplink site, such as a network operations center (NOC),to transport data back and forth to each VSAT terminal via satellite,

y A mesh topology, where each VSAT terminal relays data via satellite to another terminalby acting as a hub, minimizing the need for a centralized uplink site,

y A combination of both star and mesh topologies. Some VSAT networks are configuredby having several centralized uplink sites (and VSAT terminals stemming from it)connected in a multi-star topology with each star (and each terminal in each star)

connected to each other in a mesh topology. Others configured in only a single startopology sometimes will have each terminal connected to each other as well, resulting ineach terminal acting as a central hub. These configurations are utilized to minimize theoverall cost of the network, and to alleviate the amount of data that has to be relayedthrough a central uplink site (or sites) of a star or multi-star network.

STAR NETWORK:This is how a star data, TDM/TDMA VSAT network works using a hub station, usually six metres or morein size and small VSAT antennas (between 75 centimetres and 2.4 metres). All the channels are sharedand the remote terminals are online, offering fast response times. Consequently, TDM/TDMA systems arecomparable with terrestria


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l X.25 or frame relay connections.

Initial systems were designed to offer fast response times for predicable, bursty traffic patterns - typifiedby credit verification transactions and lottery systems. As the internet and broadband generally began todrive demand, the manufacturers introduced completely new IP-centric platforms designed to servebroadband applications. In essence, current systems are now also able to trade a short initial delay toallow the hub to allocate dedicated capacity within the inbound (return) channel to a VSAT. This capacityis dynamically sized by the system based on the traffic demand seen by the VSAT. In addition, allsystems also incorporate frequency hopping, allowing the network to be load-balanced by moving VSATs

between inbound carriers to ensure that capacity is used efficiently and congestion does not occur.


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ABOUT VSAT:

VSAT was originally intended for sporadic store-and-forward data communications but hasevolved into real-time internet services. VSAT uses existing satellite broadcasting technologywith higher powered components and antennas manufactured with higher precision thanconventional satellite television systems. The satellite antenna at the customer's location

includes, in addition to the receiver, a relatively high-powered transmitter that sends a signalback to the originating satellite. A very small portion of a transponder is used for each VSATreturn path channel. Each VSAT terminal is assigned a frequency for the return path which itshares with other VSAT terminals using a shared transmission scheme such as time divisionmultiple access.

An innovative feature of VSAT is that the technology has evolved to the point that somethingthat previously could only be done with large, high-powered transmitting satellite dishes can nowbe done with a much smaller and vastly lower-powered antenna at the customer's premises. Inaddition, several return-path channels can co-exist on a single satellite transponder, and each ofthese return-path channels is further subdivided to serve multiple customers.

ADVANTAGES OF VSAT:

Always on broadband technology

Highly secured end to end connectivity

Highest availability


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Uniform nationwide service levels

Quick deployment on all terrainsNo dependence on leased lines, dial-up, cables,etc.

Reliable CommunicationsVSAT satellite communications provide virtually error-free digital data communications andbetter than 99.9% network reliability.

Remote CommunicationsNo matter how remote or dispersed your operations are, VSATs provide a link to yourheadquarters. VSAT can provide remote diagnostics, remote monitoring, and data streamingservices from remote or hazardous sites.

System IntegrationTurnkey seamless integration of communications requirements provide a one point contact for

your private data network From design, implementation, installation and management a turnkeysolution to your communications requirements. These services are provided in an individualizedcost-effective solution.

Typical VSAT network architecture


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Figure 2. Architecture for a typical VSAT network employing a common hub and star topology.

Chapter 3


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Broadband Satellite InternetThere are several key differences between the broadband satellite Internet services offered by

VSAT Systems and the typical satellite Internet service from other providers.

Native IP with AccelerationUnlike broadband satellite Internet services that were adapted from television broadcasttechnology, VSAT Systems service was built from the ground up for IP services. High efficiencyTCP acceleration and accelerated TCP handshake enhances performance by mitigating theeffects that satellite latency typically has on TCP/IP traffic.

Dynamic Tx Power Control

A unique feature of VSAT Systems broadband satellite Internet service is its dynamic transmit(Tx) power control feature that automatically increases Tx power when necessary due to weatheror atmospheric conditions

Standard satellite Internet transmitters do not automatically manage Tx power, and thereforemust be pre-set to a Tx level that will not overpower the satellite transponder on a clear day.Therefore with a standard transmitter, upload performance can be substantially lower on cloudyor rainy days. Not so with this system. When signal strength is threatened by precipitation orother factors, additional power is automatically provided to compensate.

Advanced Satellite Internet Modem (Indoor Unit)

The VSAT Systems indoor unit (IDU) is a single-box broadband satellite Internet modem withonboard TCP optimization and QoS (Quality of Service) capabilities, router and DNS.

The unit is centrally managed from our Network Operations Center (NOC) which frees the userfrom hassles such as software updates. In fact, the IDU can also be managed remotely from theNOC for configuration changes, real-time monitoring and historical reporting.

The IDU is compatible with Ku and C band service as well as Ka band service when it becomesavailable. The VSAT Systems satellite Internet service is also available with a software load thatcan allow it to operate in site-to-site mode as opposed to its normal site-to-Internet mode. This isimportant because it means that connecting two sites directly to each other over a single

broadband satellite hop is made possible as an option to this standard broadband satelliteservice.


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HOW BROADBAND SATELLITE INTERNET WORKS

Satellites have brought Internet access to places where IP communications seemed impossible. In

this section, we explain how satellite Internet works. You will understand how bytes ofinformation or simply a mouse click travels all the way from your computer to the satellite, toour NOC and back.

VSAT Systems uses commercial satellite connections as a high-speed digital link between ourcustomers and the U.S. Internet backbone. The main components of a satellite system comprisesof the following:

1. Ground-based electronic equipmentThe VSAT dish: It refers to what most people call their dish. VSAT units are two-way satelliteground stations with dishes that typically range from 0.75m to 1.8m in diameter. VSAT Systems

offers VSAT antennas between 1.2m and 2.4m in diameter, depending on the application andlocation.The indoor modem: A satellite modem facilitates data transfers using a communications satelliteas a relay. VSAT Systems end users typically use the iDirect 3100 series Modem.The teleports: The teleport is the earth station that controls communications across the spacelink. The teleport is the heart of the VSAT Systems satellite Internet system. VSAT Systems hasthree 6.3m VertexRSI antennae, transmitters, control systems, redundant links to the Internet,plus auxiliary power and HVAC.The Network Operations Center (NOC): The facility which controls all communications over thesatellite link. The NOC monitors for power failures, satellite signal issues and other performanceissues that may affect the network. The VSAT Systems NOC is located in Akron, Ohio.

2. Satellite equipment


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The satellite: In a geostationary or geosynchronous orbit 22,236 miles above the earths surface,a satellite completes one revolution in exactly the same amount of time that it takes the Earth torotate one full turn on its axis. Thus, the satellite always appears at the same position above theEarth. This eliminates the need for satellite dishes at the user location to track the satellite, whichgreatly simplifies their construction and cost. These satellites, used for a variety of purposes like

broacast and telecommunications, can also be used to provide Internet access at any location onEarth.Transponder space segment: The communications channels on a satellite that both receive andretransmit data. Modern satellites carry between 36 and 72 separate transponders all running atdifferent frequencies. These frequency segments are used for transmission of data.Internet Backbone: The backbone is a large collection of interconnected, high-capacity,commercial, government, and academic data routes and core routers that carry data. Theyconnect with other countries and continents around the world.

3. Heres how the process works - in 5 easy to understand steps:y End user computer is connected to your network, which in turn is connected to the

Internet by VSAT Systems. You open a web browser, and type in a web address. Enduser computer sends a request for a transfer of data - both transmit and receive.

y That request is sent from the end user PC, through their home network, to the indoorsatellite modem which modulates the signal and passes it to the VSAT dish. The VSATdish converts this signal to an RF signal and sends it to a satellite located in thegeostationary orbit at the speed of light - 186,000 miles per second.

y The satellite in the geo-stationary orbit receives this signal and sends it to one of theVSAT Systems teleports in Akron, Ohio. This illustrates the fact that although the packets of information travel tremendous distances via the space segment, the packets

hop fewer networks due to the large reduction in the number of inter domain and intradomain routers giving an opportunity to minimize latency.

y The request then goes to VSAT Systems NOC, which retrieves the requested websitefrom the web server, across the U.S. Internet backbone.

y The whole cycle is then reversed and the requested data is available to the user. A 90,000mile journey, through millions of dollars of infrastructure and sophisticated equipment,all in less than 700 milliseconds.

Vsat broadband:


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VSAT broadband is similar to cable and DSL services for your computer. It is Internet servicethrough a satellite dish that is placed on your home or business. It is another option for a high-speed Internet connection that is considered to be one of the best technologies available today.

One of the greatest advantages of VSAT broadband is that you do not need any special software,hardware or networks to use it. It works with nearly any email provider and uses a satellite dishthat is like the ones used for satellite TV. A person or business can use what they have and nothave to digest and learn a lot of new information before being able to use their computer.

There are many other advantages to using this type of Internet connection. It is very easy to use,the connections are extremely fast, and the service is flexible and always reliable. For bothcompanies and individuals, this is very important. You can connect to the Internet anywhere, at

any time. This includes customer service, as well. It does not matter what time you have aquestion, there is someone available to answer it. The possibilities with this technology areendless.

VSAT broadband offers top of the line VPN encryption for the security of your personalinformation and data. They also offer full services for things like web hosting, net meeting, etc.

For companies, VSAT broadband offers a single vendor for all of their services. Theconvenience of this service is a great time saver for both small and large businesses. This makespaying bills easier, sending emails a quicker process, and allows for easy understanding amongemployees.

The cost of VSAT broadband service is comparable to other types of service. It takes only 14days to get the service, and the installation of the dish can be done in about 3-6 hours. VSATbroadband is definitely a wave of the future.

Advantages

1. True global broadband Internet access availability2. Mobile connection to the Internet (with some providers)

Disadvantages

1. High latency compared to other broadband services, especially 2-way satellite service2. Unreliable: drop-outs are common during travel, inclement weather, and during sunspot

activity3. The narrow-beam highly directional antenna must be accurately pointed to the satellite

orbiting overhead


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4. The Fair Access Policy limits heavy usage, if applied by the service provider5. VPN use is discouraged, problematic, and/or restricted with satellite broadband, although

available at a price6. One-way satellite service requires the use of a modem or other data uplink connection

7. Satellite dishes are very large. Although most of them employ plastic to reduce weight,they are typically between 80 and 120 cm (30 to 48 inches) in diameter

Interactive bi-directional data

Interactive data communications are the foundation of must corporate and government uses oftelecommunications. These needs can be addressed by properly engineered bi-directionalsatellite links that involve multiple transmitting earth stations. The Very Small ApertureTerminals (VSATs) used by fueling stations and discount department store chains in theAmericas, Europe and parts of Asia demonstrate that such networks are practical (e.g., easy toinstall and centrally manage), reliable (e.g., 99.9% availability) and cost/effective (e.g., saving

users as much as 20% over what an equivalent terrestrial network would cost).

Role of Operating GEO satellitesThe single most critical element and technology in broadband satellite communications is thesatellite itself, since every link within a common footprint must pass through it. Spacecraftdesigned and constructed in recent years are larger in physical size and mass, and providesubstantially more power than their predecessors. This results from improvements in launchers,on-board power systems, high performance components, and radio-frequency high poweramplifiers. Other components used within the microwave repeater have improved as well, withbenefits showing up in reduced component mass, lower signal loss, and enhancement oftransmission quality. A typical satellite weighs almost 5000 kg on top of the launch vehicle, hasa lifetime of 15 years, and provides between 50 and 90 channels of wideband transmission(commonly referred to as transponders) with individual power levels of up to 200 RF watts,each. A modern GEO satellite may serve relatively small antennas throughout a large area suchas the entire Euro-Asia continent or the full breath of the Pacific region

User applications and their interface standards applied in satellite communication networks.


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User application Network Technology

Internet access (oneuser; small group;remote site)

High speed access to Internetbackbone; TCP/IP

1.One way over satellite; terrestrialreturn

2.Two way over satellite; broadcast

outbound with multiple accessinbound

Remote access tocorporate Intranet (LANextension)

High speed access to privatenetwork infrastructure; web-based applications; TCP/IP

1.One way over satellite; terrestrialreturn

2.Two way over satellite; broadcastoutbound with multiple accessinbound

Remote access tocorporate businessapplications

Medium to high speed accessto private networkinfrastructure; applications

employ client/server ormainframe style; may employproprietary protocol

1.Two-way over satellite; broadcastoutbound with multiple accessinbound

2.Two way over satellite; point-to-point circuit, either pre-assigned ordemand assigned

Content distribution Multi-cast uplink for widearea distribution to PCs andcontent caching servers;UDP/IP and MulticastTransport Protocol (MYP

One way over satellite; verificationof 100% reception via terrestrial orsatellite return

Video teleconferencing High speed access to privatenetwork infrastructure or

public ISDN; H.320 or H.323standards

1.Two-way over satellite; broadcastoutbound with multiple access

inbound

2.Two way over satellite; point-to-point circuit, either pre-assigned ordemand assigned

Telephone Low to medium speed accessto private networkinfrastructure or PSTN; POTSor VoIP standards

1.Two-way over satellite; broadcastoutbound with multiple accessinbound; echo cancellation

2.Two way over satellite; point-to-point circuit, either pre-assigned or

demand assigned; echo cancellationLeased line Medium to high speed

connection; T1/E1Two way over satellite; point-to-point circuit, pre-assigned

Chapter 4


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HughesNet VSAT Environment

The graphic shows how the remote terminal or VSAT fits into the HughesNet system architecture. Let's start by clearly defining

what is meant by VSAT:

VSAT -- Per Webopedia.com (http://www.webopedia.com/): VSAT is Short for Very Small Aperture Terminal. A VSAT is anearthbound station used in satellite communications for data, voice and video signals, excluding broadcast television. A VSATconsists of two major parts, as follows:

A transceiver - This is placed outdoors in direct line of sight to the satellite. It is part of the Feed Arm attached to the dish.

A device that is placed indoors, to interface the transceiver with the end user's device. This is your HughesNet satellite modem.

The transceiver receives and sends signals, to a satellite transponder in the sky. The satellite transponder receives and sends

signals, to a ground station computer located at the HughesNet NOC (Network Operations Center).

Each end user is interconnected with another computer at the NOC, via the satellite, forming a star topology. It is also called theHub and Spokes topology. The computer at the NOC (the Hub ) controls the entire operation, for its portion of the network. For oneend user to communicate with another, the transmission has to first go to the Hub, which then retransmits it (via the satellite) to

the other end user's VSAT.

Pointing the Antenna :


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The antenna uses a three axis pointing system, which you will adjust, after you move:

Azimuth - This is the magnetic compass direction (angle of sighting) at which you point the dish. It is aside-to-side adjustment.

Elevation. - This is the angle above the horizon, at which you point the dish. This is an up-and-downadjustment.

Polarization - The polarization or skew is set after each move. This is a rotational adjustment

HughesNet System Components


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The figure above illustrates the four major components of a HughesNet VSAT system:

The Outdoor Unit (ODU) - This comprises the antenna and the feed arm, which has the receiver andtransmitter.

The Indoor Unit (IDU) - This is the HughesNet Model DW6000, DW7000, or HN7000S satellite modem.

The Interfacility Link (IFL) Cables - The cables connect the IDU to the ODU.

The Software - This is contained in the firmware of the satellite modem

VSAT COMPONENTS

VSAT Indoor Unit (IDU)

The IDU is connected to the ODU by the IFL Intra facility link .In consumer satellitetelevision applications, the IDU usually consists of a satellite receiver which is connectedto a television.In consumer satellite Internet applications, the IDU usually consists if asatellite modem which is connected to a computer or a router.


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Fig:HughesNet Satellite Modem

he HughesNet Model DW6000, DW7000, or HN7000S modem supplies DC power to the LNB and the

transmitter. It also transmits the inroute signal and receives the outroute signal. Both outroute (received)

and inroute (transmitted) signals operate at L-band, between the modem and the outdoor electronics. The

numbers in the illustration above indicate the order in which the lights come on, after a normal power reset.

The DW6000 can no longer be commissioned.

The HughesNet Satellite Modem LightsThe lights on the HughesNet satellite modems provide you with status information. Which lights are on or off

can help you pinpoint a problem, when it occurs.

The Vsat Outdoor Unit ODU


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The ODU or antenna includes the dish, or reflector, and the feed arm, which holds the active elements (transmitter and receiver).These are pictured above

The Dish or ReflectorThe older dish, shown on the left with the TV attachment, is made of fiberglass, with an embedded wiremesh. It measures 0.74 meter in surface area (39" x 23"). The newer Raven dish is still .74 meter, but isrounder (34 1/4" x 28 1/2") and it is made of a lightweight metal. Often, when only referring to the dish,without the feed arm, the term reflector is used. The latest Prodelin dish was shown earlier.

The Feed Arm

Located on the fully assembled VSAT dish assembly, the Rx-Tx feed arm is normally removed and safelystored, as part of the process for moving to a new location. The feed arm consists of the feed support armand the outdoor electronics.

All of the active outdoor components connect to the support arm, which also adds strength (and weight) tothe completely assembled antenna. The outdoor electronics consist of the LNB, which receives outroute(from the NOC) Ku-band signals from the satellite, and the transmitter, which transmits inbound (to theNOC) Ku-band signals to the satellite. Power is supplied by the HughesNet satellite modem. For those whoare interested, this is discussed in more detail, below.

LNBThe Low-Noise Block down-converter (LNB) is used to amplify and frequency convert outroute signalsreceived by the antenna, for input into the modem via the Sat-In cable.

The antenna receives the outbound signal in the Ku-band frequency, for input to the wave guide end of theLNB. The LNB first amplifies the input Ku-band signals. It then uses a local oscillator (LO), to frequencytranslate input signals to L-band frequencies, which are used on the coaxial cables.

The signal noise value is an electrical specification for the LNB, which is critical to outroute signal (yourreceived signal) quality performance. The lower the noise figure, the better the signal quality performancewill be.

The LNB is powered from the modem, via a DC power supply coupled on the coaxial RF input connector,which connects to the receive IFL cable.


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TransmitterThe transmitter is used to frequency translate and power amplify inroute signals from the modem and

output them to the antenna, for transmission to the satellite.

The modem sends the inroute signal at an L-band frequency to the transmitter, using Sat-Out and thetransmit coaxial cable. This signal is input to the transmitter, where it is frequency converted to the transmitKu-band frequency, using a nominally fixed local oscillator (LO). This Ku-band signal is then power amplified

to operate the transmitter at a nominal one-watt output power (at saturation). The fixed output power isinput to the antenna, for transmission to the satellite.

The transmitter is powered from the modem, via a DC power supply coupled on the coaxial RF outputconnector, which connects to the transmit IFL cable

Ku-bandCommunications satellites send and receive electromagnetic Ku-band signals, which are in the super high-frequency range. Microwave phone signals, which are relayed between tall towers, are in this samefrequency range. However, satellite Ku-band signals are usually not susceptible to interference from thesetowers.


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Chapter 5

Basic multiple access and modulation schemes

Effective and efficient satellite communications depends on the type of modulation and multipleaccess used by transmitting user terminals and earth stations. The staunch support by suppliers oftheir particular approach often produces interesting and confusing debate within the technicalcommunity. Mirroring the dialog of the digital mobile (cellular) standards, satellite multipleaccess techniques run the gamut of time division, frequency division and code divisionapproaches. The suppliers of two-way products have chosen a scheme for reasons of experienceand capability. Evaluation of these systems is ongoing, and each can demonstrate satisfactoryoperation in a live network. Any of the three can be made to work; however, it is likely that oneor two may be superior for a specific defined application. Beyond the theory, it is the productdesign and protocol operation that matter as to how well the multiple access system delivers

information in an effective and manageable way.

The two fundamental techniques are:1)FDMA2)TDMA

Frequency Division Multiple AccessIn FDMA scheme, different stations in the network / channels in a station are separated infrequency domain and a pair of frequency (one each for up link and down link) is assigned toeach station.

This is the oldest and the simplest form of multiple access scheme.

Time Division Multiple AccessIn TDMA the separation of different stations with respect to the satellite is done in the timedomain. Each station / traffic channel is allotted specific timeslots over which they transmit thedata in a burst mode.


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VSAT using FDMA

1 3 L2

wast

sat

lit

capacit

fr

c

ti

it rat

Rc

1

acti

2

no trafic

3

acti

L

acti


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VSAT using TDMA

frequency

time

bit rate c

1

active

2

no trafic

3

active

1

2

3

L

wasted satellite capacity

TDMA frame

duration

L

active


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Chapter-6

VSAT Data Capacity

The indoor data processing unit (DPU) or satellite modem will typically have one or more user etherentports for connection either direct to PCs or to a local area network router. The number of ports istypically 1 or 4.

If your modem has just one etherent port you can extend it to 4, 8, 16 etc as required using local areanetwork hub devices or switches.

Download bit rate

In the outlink (download) direction from the hub to the VSATs continuous carriers are used, typically morethan 256k bit/s and up to 60 Mbit/s. The type of carrier is almost identical with a digital TV carrier calledDVB-S. Each VSAT is restricted to extract from the data stream only those packets of data intended forit. One outlink may be shared by 5 to 32,000 VSAT sites, according to the traffic load.

In some cases you can use a DVB-S type receiver to receive only and still extract just what is intended foryou. This is the basis for DVB-S/SCPC systems where the VSAT uses a separate transmit modem totransmits a low speed continuous carrier back to he hub. The DVB-S arrangement also applies to socalled one-way satellite internet systems that use a DVB-S plug-in card in your PC. In this case thecustomer sends request packets to the hub using a terrestrial phone line/modem. The benefit is highspeed downloads.

Upload bit rateThe data transmission rate on the return link, in the direction from the VSAT to the hub, is typically from afew 100 bit/s to 512 kbit/s. Each VSAT typically transmits in short occasional bursts, interleaved in time.The number of VSAT sites sharing a return link and the number of return links is adjustable to matchactual traffic patterns, hopefully without unacceptable congestion. Sharing ratios vary from 5:1 to 60:1The higher sharing ratios correspond to least cost services, suitable for the occasional undemandinguser. Shared systems are vulnerable to greedy users who may quickly overload the network.

Where reliable return link bit rates are required such as for business, cyber cafe or VoIP applications acontinuous return link carrier is used (SCPC = Single channel per carrier). It is also possible to set up adedicated repeating time slot in a TDMA system which gives the same equivalent result - a continuousguaranteed bit rate for the customer. This has the advantage that any congestion that does occur is fully

under the customer's control.

VoIP requires approx 20 kbit/s each way for the duration of the call and most satisfactory results areobtained with dedicated capacity.


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Calculation of link margin

1.Down link rain attenuation ain fall introduces attenuation by absorption and

scattering of signal energy, and the absorptive attenuation introduces noise.Effective noise temp of rain asTrain =TA(1-(1/A))Where TA is known as apparent absorber temperature. It is a measured parameter,which is a function of many factors, including physical temperature of rain, andscattering effect of the rain, and the scattering effect of the cell on the thermal noiseincident up on it. The value of the apparent absorber temperature lies between 270 and290 K .Total sky noise temperature is the clear sky temperature plus the rain temperature

TSky= Tcs+T AIN

Where TCs is the clear-sky noise temperature

2. eceiver antenna pointing loss When a satellite link is established, the ideal situationis to have the earth station and satellite antennas aligned for maximum gain. There aretwo possible sources of off axis loss , one at the satellite and one at the earth station .The off axis loss at the satellite is taken in to account by designing the link for operationon actual satellite antenna contour. The off axis losses at the earth station is referred toas the antenna pointing loss.

Antenna pointing losses are usually only a few tenths of a decibel.

3.Eb/No required for BE of 1/ 10

7

It is Signal to noise ratio required to achieve BitError atio of 1 error bit per 107 message bits.

4.Down link C/No (dB Hz) It is the down link carrier to noise ratio. It can be calculatedas follows.

Down link C/No(dB Hz) = Satellite operating EI P - Downlink path loss - Down link rainattenuation - eceiving antenna pointing loss + eceiver G/T +228.6.

.[15]

Example : Calculate Down link C/No(dB Hz) for the Satellite operating EI P =-6.23 dB W, Downlink path loss =195.74 dB, Down link rain attenuation=0 dB,eceiving antenna pointing loss = 0.70 dB, eceiver G/T =22.58(dB/K)

SolutionDown link C/No(dB Hz) = Satellite operating EI P - Downlink path loss - Downlink rain attenuation - eceiving antenna pointing loss + eceiver G/T +228.6.

= -6.23-195.74-0-0.70+22.58+228.6= 48.51 dB Hz


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5.Over all Down link C/No (dB Hz) It is the some of carrier to noise ratio at the downlink and carrier to noise ratio at the up link. It can be calculated as follows Over all Downlink(C/N0) (dB Hz)= -10*LOG (10

-(C/No)U+10-(C/No)D)..[16]Here

(C/No)U = Up link C/N ratio.(C/No)D = Downlink C/N ratio.It is the effective C/N ratio of the total system (Transmitter & receiver )

Find over all carrier to noise ratio of the satellite Up link C/N ratio = 61.95,Downlink C/N ratio= 48.51Over all Downlink(C/N0) (dB Hz)= -10*LOG (10

-(C/No)U+10-(C/No)D)= 48.32

Available Eb/No It is the ratio of signal to noise ratio of the system. It can becalculated as follows.

Available Eb/NO = over all downlink (C/No) / Input data rateAvailable Eb/NO (dB)= Over all downlink (C/No)(dB) - Input data rate (dB)= Over all downlink(C/No)(dB) 10log (input data rate in

KB*103)...[17]

Find Available Eb/NO (dB) for the satellite Over all downlink (C/No)(dB) =48.32,Input data rate (dB)= 9.6 KB/S.Available Eb/NO (dB)= Over all downlink(C/No)(dB) 10log (input data rate inKB*103 = 48.32- 10 log(9.6 * 103)

= 8.63 dB.Available link margin It is the Difference between Available Eb/No and Eb/Norequired for BE of 1/107 in dB.

Available link margin = Available Eb/No(dB) Eb/No required for BE of 1/107 (dB)

..[18]

Find Available link margin for the satellite Available Eb/No(dB) =8.63 and Eb/Norequired for BE of 1/ 107 (dB) = 6.5.

Available link margin = Available Eb/No(dB) Eb/No required for BE of 1/ 107

(dB)

= 8.63-6.5 = 2 dB.


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Chapter-7

Earth Station

The Raisting Satellite Earth Station is the largest satellite communications facility in Germany.

An earth station, ground station, orearth terminal is a terrestrial terminal station designed forextraplanetary telecommunication with spacecraft, and/or or reception of radio waves from anastronomical radio source. Earth stations are located either on the surface of the Earth, or withinEarth's atmosphere Earth stations communicate with spacecraft by transmitting and receivingradio waves in the super high frequency or extremely high frequency bands (e.g., microwaves).When an earth station successfully transmits radio waves to a spacecraft (or vice versa), itestablishes a telecommunications link.

Earth stations may occupy either a fixed or itinerant position. Article 1 III of the ITU RadioRegulations describes various types of earth stations, stationary and mobile, and theirinterrelationships.

Specialized satellite earth stations are used to telecommunicate with satelliteschieflycommunications satellites. Other earth stations communicate with manned space stations orunmanned space probes. An earth station that primarily receives telemetry data, or that follows asatellite not in geostationary orbit, is called a tracking station.


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When a satellite is within an earth station's line of sight, the earth station is said to have a view ofthe satellite. It is possible for a satellite to communicate with more than one earth station at atime. A pair of earth stations are said to have a satellite in mutual view when the stations share

simultaneous, unobstructed, line-of-sight contact with the satellite

Telecommunications port

A telecommunications port or, more commonly, teleport is a satellite earth station withmultiple antennas (i.e., an antenna farm) that functions as a hub connecting a satellite orgeocentric orbital network with a terrestrial telecommunications network.

Teleports may provide various broadcasting services among other telecommunications functions,

such as uploading computer programs or issuing commands over an uplink to a satellite.

Earth terminal complexes

In Federal Standard 1037C, the United States General Services Administration defined an earthterminal complex as the assemblage of equipment and facilities necessary to integrate an earthterminal (earth station) into a telecommunications network FS-1037C has since been subsumedby the ATIS Telecom Glossary, which is maintained by the Alliance for TelecommunicationsIndustry Solutions, an international, business-oriented, non-governmental organization.

Although the ATIS as well as the Telecommunications Industry Association acknowledge this

definition, the occurrence of the wordco

mplex in the name of a radio observatory or other majorearth station, doesn't necessarily connote all of the nuances of the FS-1037C definitionespecially outside of the United States.

Satellite communications standards

The ITU Radiocommunication Sector (ITU-R), a division of the InternationalTelecommunication Union, codifies international standards agreed-upon through multinationaldiscourse. From 19271932, standards and regulations now governed by the ITU-R wereadministered by the Comit consultatif international pour la radio (International ConsultativeCommittee for Radio).

In addition to the body of standards defined by the ITU-R, each major satellite operator providestechnical requirements and standards that earth stations must meet in order to communicate withthe operator's satellites. For example, Intelsat publishes the Intelsat Earth Station Standards(IESS) which, among other things, classifies earth stations by the capabilities of their parabolicantennas, and pre-approves certain antenna models. Eutelsat publishes similar standards andrequirements, such as the Eutelsat Earth Station Standards (EESS).


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Case Study - VSAT Connectivity

Connectivity: The VSAT way

VSAT is a secure and reliable medium to connect geographically dispersed locations. In a

situation where other connectivity options are not feasible, VSAT offers two distant advantages:less deployment time and easy manageability. A look at how Comsat Max has created a VSATnetwork that connects remote and major locations nationwide and the advantages your companywill gain if you go the VSAT way.

Comsat Max's VSAT (Very Small Aperture Terminal) network provides nationwide data andvoice connectivity to enterprises. Support for the VSATs is provided from 50 locations spreadacross the country. It has an extended C-Band hub in Turbhe (New Mumbai), and has builtanother hub which runs on the Ku-Band, very recently in New Delhi. The network topology is a

mix of star and mesh.

Comsat Max started its operations in 1995. "At that time, we felt that there was a need forreliable and managed WAN solutions," said C S Raghava Rao, Head - Technical operations,Comsat Max Limited. "The predominant method of WAN connectivity was leased lines whichhad several disadvantages. The lines were costly and one had to apply for a leased line and waitweeks for a connection. Leased lines have bandwidth slabs and can't be shared on a network basis. Thus the capacity is underutilized. In a large network sharing of bandwidth helps inoptimal use of resources, VSAT technology provides speedy, cost effective and reliable solutionsto the organization."

A VSAT is a small fixed earth station which provides a communication link required to setup asatellite-based communication network. It represents a cost-effective solution for those who wantan independent communications network to connect a large number of geographically dispersedsites, especially sites where any other connectivity options are not possible to implement.

SAT networks offer value-added satellite-based services capable of supporting the Internet, data,LAN, voice/fax communications, and can provide powerful, dependable, private and publicnetwork communications solutions. A VSAT has certain clear advantages over leased lines andother wireless communications media.

VSAT value over cable

When it comes to cost its not quite fair to make general comparisons between VSAT servicesand it's terrestrial counterparts. Charges for terrestrial services are nearly always distance-dependent, while VSAT connections cost the same whether sites are one or 1000 Km apart. And


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with most VSAT services the cost-per-connection comes down considerably when a customeradds users. However, Comsat Max and other VSAT service providers have considerably reducedtheir fees lately.

A satellite network can be installed and made operational within a week since miles of cable

need not be installed. And VSATs are available in remote locations since it doesn't need theinfrastructure of a telephone exchange to be present.

"Suppose a bank needs to expand it business by deploying 100 new ATMs (Automated TellerMachines) within six weeks, can you imagine the time it will possibly take to wait for leasedlines? In such a case, VSAT connectivity is the best option,".

Traditionally, VSATs had a few disadvantages: VSAT bandwidth was not very high andrestricted to a few 100 Kbps. There was also certain amount of latency (the time betweeninitiating a request for data and the beginning of the actual data transfer) between nodes. Butthese limitations have been overcome to a large extent due to advancement in technology.

Nowadays, VSAT providers offer up to 52.5 Mbps outroute (from hub to VSAT) and 307.2 Kbpsinroute (from VSAT to hub) data rates, and only 270 millisecond latency.

The young VSAT provider

In 1995 Comsat Max started service using AT&T Clearlink systems (satellite modems capable ofhandling TDM/TDMA traffic).

This enabled its clients to use a dedicated data transmission network and ensured reliability of

transmission. The system offered 64 Kbps inroute and 512 Kbps outroute data rates. The hub atTurbhe used an extended C-band antenna and TDM/TDMA technology to support VSATs on astar topology. C-band is used extensively in Asia, Africa, and Latin America and requires alarger antenna than Ku-Band VSATs. The company had direct presence in eight cities andfranchises in 30 cities.

In early 1997, the DoT (Department of Telecommunications) allowed the company to build amesh network. This allowed an easier passage for high-speed low-latency networks because itreduced a hop, otherwise present in a star topology.

In 1999 the company deployed Skystar Advantage LAN+ using FTDMA (Frequency & Time

Division Multiple Access) technology. This reduces probability of collisions and can supportinteractive transactions, batch file transfers, data broadcast, and voice communications. Broad-cast of audio and video are available as add-on options.

A blast of broadband

Comsat Max now uses SkyBlaster 360E (a Ku-Band VSAT) which uses a DVB (Digital VideoBroadcast) standard to offer broadband Internet access to its customers. The product is a two-


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way satellite-based solution to enable interactive Broadband IP and multicasting applications. Byusing the DVB standard and IP capabilities, the SkyBlaster 360E supports most data and IPmulticast applications. The product works on Ku-Band-based networks which are mostly used inEurope and North America. The company uses the services of the INSAT-3B satellite.

The platform is able to network the central hub with multiple locations spread across widegeographical areas. "It's possible to provide outroute speeds upto 52.5 Mbps and inroute datarates upto 307.2 Kbps,". "The SkyBlaster allows us to provide HTTP traffic acceleration andoptimization, caching capabilities, QoS (Quality of Service), multimedia streaming applicationslike voice and video, and IP multicast applications."

A dash ofVPN

"Although a VSAT network offers very high security, we believe that our customer should beoffered more flexibility in the form of a dedicated network with high bandwidth, low latency,and assured connectivity,". This prompted Comsat Max to set up an Internet infrastructure to beused along with the VSAT architecture to offer Internet and VPN services in 17 citiesnationwide.

Service differentiator

"What makes a difference is not the technology but the people in our organization who drive thesolutions. A state-owned airline and a private-owned airline both run Boeing 737 aircrafts. Butwhy do you think passengers prefer to fly private airlines? It's the difference in levels of serviceand commitment to customers,".

Management"Since we have a very large network and different platforms/ devices like indoor and outdoor


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units and routers, we had to choose a unified network management platform that gave us anintegrated view. We decided to use Computer Associates' Unicenter TNG. It provides anintegrated interface that enables us to keep a tab on the entire network from one screen. It alsoprovides audio and visual alerts. If a device goes down, the system opens a trouble ticket (a kindof a maintenance request). If the problem is not solved soon, the ticket is escalated to a person of

higher authority in the form of an SMS ore-mail message,".

Myth

The cost of VSAT services has decreased dramatically in the last few months. This is indeed agood sign for large enterprises and smaller companies who are poised for growth.

"It is a myth that VSAT has seen its end. Around 30 percent of all communications worldwiderely on VSAT, and its deployment keeps increasing," .


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VSAT Systems vs. The Competition

VSAT Systems is a superior business partner because we offer superior satellite connectivity.This is true because we have invested millions in performance enhancing infrastructure andtechnologies. As you consider potential partners, we ask that you consider the following:

VSAT Systems can guarantee extraordinarily high QoS because we control all the variables thataffect quality. We run our own NOC and staff it with highly technically skilled professionals

who monitor and optimize the network 24/7, 365 days a year. We also own our own satelliteuplink teleport. We also offer our customers the capabilities to remotely monitor and controlnetwork operation and performance.

VSAT Systems is a Tier-1 operator with direct access to the Internet backbone. In fact, we haveredundant access points to ensure connectivity at all times.

VSAT Systems 99.992% average reliability soars above the competition. This is no accident.We use only business grade technology in everything from modems and routers to larger end-user dishes that boost signal reception. Unlike many providers, our satellite space cannot be

preempted in emergency or high load situations.

VSAT Systems has answers for latency and rainfade. Again, the secret is better technology.Compare our low system latency of < 650 ms to anyone else in the field. Also, ask if they canminimize rainfade with Dynamic Tx power modulation. We can and do, every day.

VSAT Systems backs its up-to speeds with Committed Information Rates (CIRs). Up-to speedsmean nothing if everyday levels fall short because of over-subscription. When we add customers,we add bandwidth. And we guarantee CIRs.

In a word, the difference is confidence.Because VSAT Systems is a Tier-1 operator with direct access to the Internet backbone because we own and control the quality of both our teleport and NOC because weve investedin advanced technologies that neutralize the ill effects of weather and system latency ourVARs, VNOs and Dealers can deliver supremely reliable broadband to demanding customers.This is a formula for success.


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VSAT Systems Satellite Internet Rate Plans

VSAT Systems offers several broadband satellite Internet service plans including4.09Mbps/1.5Mbps. The wide range of satellite Internet plans offered are designed to help usmatch your needs to your budget. These plans are available to our end users through one of ourpartner resellers. All our plans come with CIRs- guaranteed speeds.

Our most popular plans, are a great starting point for discovering the right mix. These servicelevels are designed for companies in the oil, gas and mining industry, remote businesses or anyoperation that will use VSAT Systems satellite Internet as the primary form of connectivity. Wehave other service plans to meet occasional, short-term, or back-up connectivity needs.

VSAT Customer Applications

1.Broadband direct to the home. e.g. Downloading MP3 audio to audio players.2.Broadband direct small business, office etc, sharing local use with many PCs.

3.Internet access from on board ship Cruise ships with internet cafes, commercial shippingcommunications.

4.Military, data transfer, voice, temporary fixed and mobile VSAT.5.Environmental monitoring, weather stations, seismic monitoring.


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Conclusions

VSATs are most commonly used to transmit narrowband data (point of sale transactions such as credit card, pollingor FID data; or SCADA), or broadband data (for the provision of Satellite Internet access to remotelocations, VoIP or video). VSATs are also used for transportable, on-the-move (utilising phased array antennas) ormobile maritime communications.

Many people are curious about weather issues with a satellite Internet connection. Although theweather can impact your satellite TV use, this does not happen with VSAT technologies. Thedish is larger, which makes weather problems almost nonexistent. The only requirement for thisdish is being able to place it so that it faces the southern sky to access the satellite. The satellitecoverage of the planet is also quite extensive, so that you can have the high-speed access youdesire almost everywhere.

There are many other advantages to using this type of Internet connection. It is very easy to use,the connections are extremely fast, and the service is flexible and always reliable. For bothcompanies and individuals, this is very important. You can connect to the Internet anywhere, atany time. This includes customer service, as well. It does not matter what time you have aquestion, there is someone available to answer it. The possibilities with this technology areendless.

Advances in technology have dramatically improved the price/performance equation of FSS (Fixed Service

Satellite) over the past five years. New VSAT systems are coming online using Ka band technology that promise

higher bandwidth rates for lower costs.

FSS satellite systems currently in orbit have a huge capacity with a relatively low price structure. FSS satellite

systems provide various applications for subscribers, including: telephony, fax, television, high speed data

communication services, Internet access, Satellite News Gathering (SNG), Digital Audio Broadcasting (DAB) and

others. These systems are applicable for providing various high-quality services because they create efficient

communication systems, both for residential and business users.

what exactly is a vsat

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