By James Careless

Today more than ever, secure communications matter; whether for maintaining homeland security, protecting privacy or just keeping competitors’ prying eyes at bay. This is why businesses and governments alike constantly seek the most secure transmission paths for their communications and why they continue to choose satellite-enabled networks as their medium of choice.

"When it comes to which communications medium is the most secure, the proof is in the pudding," says David Hartshorn, secretary general of the Global VSAT Forum (GVF). "Take the U.S. military, who has mission-critical communications requirements where no compromise of security is allowable: They choose satellites."

It is important to note that content traveling over a terrestrial network often is embedded with encryption layers. With the increasing growth of hybrid networks in play today, however, one of the main reasons satellite is being incorporated into a network platform is for secure backup when terrestrial links fail. Likewise, content is becoming more complex, requiring more bandwidth and the need to reach more end user sites. With these increased requirements, securing that content from origination to destination is more paramount and in most cases more economical for the customer when satellite is added rather than expanding terrestrially.

"Requirements continue to expand rapidly in terms of bandwidth, supporting services and global coverage. In fact, the Defense Department estimated 80 percent of the satellite communications capacity needed for Operation Iraqi Freedom was provided by commercial satellites," says David Helfgott, president and CEO of Americom Government Services, a wholly-owned subsidiary of SES Global.

In addition to military operations, government agencies and commerce operations also rely on satellite-enabled platforms to transmit content. "The United Nations uses satellite communications to link its global network of atmospheric monitoring stations in order to ensure compliance with the Nuclear Test Ban Treaty," adds Hartshorn. "And in Asia, most major stock exchanges rely on satellite systems to move transactional data in and out of their exchanges quickly, reliably and securely."

The Advantages Of Satellite For Secure Communications

At first glance, one might question the sense of comparing satellite versus terrestrial (wired landline) transmissions for secure communications: Isn’t it the actual encryption of the signal that makes it secure, rather than how it is transmitted?

It could also be argued that satellite carriage is actually less secure than terrestrial. After all, can’t anyone eavesdrop on a satellite signal simply by pointing a dish in the right direction? In contrast, to intercept a terrestrial transmission you have to find the wire and tap it physically; an act that takes more time and runs a higher risk of detection.

Logically, these points make sense; so why do the U.S. military, the United Nations and Asian stock exchanges rely on satellite for their highest-priority transmissions?

Satellite Offers Control

In a perfect world, one would control every link in the transmission chain, from the origination point to the reception site thousands of miles away.

This level of control is possible with satellite. Simply send the signal skywards to a geostationary satellite 22,300 miles up, then bounce it down to a receive site on the other side of the world. As long as you control the uplink site and the satellite–whether through ownership or contract–the transmission path is yours to command.

In contrast, signals sent over landlines have to travel through different jurisdictions and nations. Even in one’s own country, chances are that these lines are owned by a number of third-party carriers. As a result, terrestrial transmissions can be more of a challenge to fully monitor from beginning to end.

In fairness, there are cases in which a single satellite hop cannot reach far enough to make the connection. This is where inter-satellite signal switching comes into play. By switching signals from one spacecraft nearest to the uplink site to another spacecraft closest to the downlink site, satellites can provide a secure path that is literally worldwide. For instance, a single earth station in Hawaii "can send signals over the North pole to military units in Iraq," says Roger Rusch, president of TelAstra, Inc., a satcom consultancy located in Palos Verdes, CA. "This signal can then be relayed through the constellation around the world, which means this single earth station has global transmission path control."

Reliability When Required

Satellite networks also tend to be less vulnerable to natural and man-made disasters than telephone lines and radio towers. This is why governments and businesses worldwide are adopting satellite technology for their most important "must not fail" communications missions.

When the attacks on the World Trade Center occurred, the Fire Department of New York (FDNY) was crippled by failed terrestrial radio and telephone communications. That is not all. "When 9-11 was in progress, there were no live video feeds from the scene being sent to FDNY HQ," says FDNY Chief of Safety Allen Hay. "As a result, the people at the command level did not have a picture of what was going on."

To solve this problem and reduce its reliance on vulnerable terrestrial communications, the FDNY is field-testing satellite videophones, using uplinks and equipment provided by Stratos Global Corp. The goal is to use videophones to show the FDNY’s Brooklyn headquarters exactly what is happening at an incident and to let officers there videoconference with on- site commanders in real time.

To do the job, Stratos installed a suitcase-based 7e Communications "Talking Head" videophone inside an FDNY command sport utility vehicle. "It has everything you need inside the suitcase," says Alex Achille, the FDNY’s director of technical operations. "You open it up, and there is a built-in camera, built-in microphone and a built-in liquid crystal display video screen and speaker; along with the controls to initiate the call."

To get the signals to and from the incident scene’s videophone-equipped vehicle, "we have installed two Inmarsat GAN [Global Area Network] antennas on its roof," says Larry Engelbert, Stratos manager of government sales. Built into low-profile dome housings, these EMS Technologies’ PDT-100 antennas "are equipped with movable self-tracking systems that keep them pointed at the right satellite," Achille says.

Based on field tests to date, the FDNY’s satellite-based videoconferencing system "works pretty well, about 95 percent of the time," says Hay. "Had satellite videophones been deployed on 9-11, things might have been different," he adds. "At the very least, people at headquarters would have had a better situational awareness of what was going on and would have been able to provide more help to the people at the scene."

Portable And Quick To Deploy

Besides offering transmission path control and reliability, satellite communications also can be portable and quick to deploy, two reasons why they have been adopted for use by the U.S. military and TV journalists around the world.

The same advantages explain why satellite communications also are used by disaster relief agencies, especially because satellite services such as Inmarsat, Iridium and Globalstar provide near-global coverage. "With satellite communications, you can just jump in a truck and head to the scene knowing that you can get a signal out," says Rusch. This is not the case with terrestrial carriers. Their infrastructures often do not reach into remote areas and, if they do, are prone to failure during natural disasters such as earthquakes, hurricanes and tsunamis.

Advanced Encryption Solutions Remain In Demand

As more users increase their need for advanced secure transmission portals, more developments for products services that provide reliable signal encryption via satellite are in high demand.

Maryland-based V-One Corp. specializes in providing secure end-to-end transmission solutions for government and business customers. One of its clients is the U.S. Federal Bureau of Investigations (FBI), which wanted to connect bomb disposal squads with the Bureau’s Bomb Data Center in Washington, DC. The goal was to provide officers faced with the potentially lethal task of defusing bombs with up-to-date information and expert assistance, no matter where the incident was taking place.

Given the deployment and reach of satellite coverage, plus a mobile satellite truck’s ability to go anywhere, satellite was the obvious transmission path for this project. But what about signal security, plus the time delays caused by sending data up to a satellite and back again? To meet both challenges, V-One supplied the necessary encryption software to the FBI and its proprietary Smartsat VPN (virtual private network) software.

"SmartSat deals with the latency problems of satellite transmission, which play havoc with conventional TCP/IP data transfers, by using a technique known as ‘TCP spoofing’," says Margaret Greyson, V-One’s president and CEO. "In a conventional TCP/IP network, the data sender requires confirmation that the first data packet has been received before it will send a second packet. Given the quarter-of-a-second time delay on a satellite network, this can slow traffic to a crawl. To prevent it, the TCP spoofer fools the data sender into elieving that the confirmation has been sent, so that the subsequent data packets flow without interruption."

Netherlands-based Irdeto Access and United Kingdom-based NDS both provide conditional access software to the pay-per-view TV (PPV) industry. Both companies’ software is vital to the health of the PPV industry on satellite and cable TV.

"Our products enable the PPV operator to receive the revenue they are entitled to, by ensuring that only paying, authorized customers can decrypt the incoming PPV signal," says Bo Ferm, Irdeto Access’ regional manager for the Americas. "To deter pirates, our software can be set to change the required encryption key every ten seconds. This means that even if a person could somehow figure out which 64- or 128-bit key is being used to encode the video, their success would be extremely short-lived."

The Bottom Line

When it comes to secure signal transmission, satellite can play a strategic role for delivering data for both business and government users. The "proof of this pudding," to quote Hartshorn, is the number of military and Fortune 500 clients who rely on encrypted satellite transmission each and every day for their mission-critical communications. Satellite’s portability, fast deployment and ability to go where terrestrial network cannot make this delivery mechanism a strategic choice.

System administrators in charge of disseminating content through corporate networks must keep security as one of the most important elements in the transmission regardless of what the content relays. As business arenas become more competitive, content more proprietary and corporate networks more complex, securing information through a reliable system becomes crucial. For any client, be it commercial or government, tasked with the responsibility of keeping information securely flowing from Point A to Point B, implementing satellite-enabled encryption network can very well become one of the strongest defenses in avoiding leaked or lost information, downed systems and non-encrypted content falling before the eyes of those not meant to see it.

James Careless is senior contributing writer to Via Satellite Magazine.