Welcome!

Mobile IoT Authors: Liz McMillan, Yeshim Deniz, Ed Featherston, Carmen Gonzalez, Heitor Faroni

Related Topics: Mobile IoT

Mobile IoT: Article

Space Shuttle Wireless Part 3

Space Shuttle Wireless Part 3

In this concluding part of a three-part series on the space shuttle, WBT's David Geer looks at spread spectrum technology and its role in keeping encrypted data secure.

The communications link to the orbiter is a spread spectrum link, a technology that was invented by Hedy Lamar (believe it or not!) during WWII for secure radio transmissions. Spread spectrum makes signal jamming and eavesdropping much more challenging, an important issue for a radio signal coming from orbit, which could be intercepted from anywhere within its footprint. Eavesdropping can also be used to interfere with satellite transmissions via availability attacks, wherein interference from the other channel makes the signal unavailable.

The spread spectrum link uses a modulation scheme in which there are only 72KB of actual data sent. The data is convolutionally encoded (a complex form of modulation, which provides for error correction). This high data rate is like "taking an 11MHz signal and modulating that on top of the 72KB of coded data," says Phil Liebrecht, associate director and program manager for Mission Services, NASA Goddard Space Flight Center.

The process modulates 72KB of data with a much higher pseudo-noise code, which gives the orbiter link protection against interference from other RF signals. It also provides protection for those other signals to keep the orbiter signal from causing interference to the other S-band systems that are in use on earth. This interference could come from signals such as microwave links.

Encryption
Encrypted data can be delivered over almost any radio band, in space or otherwise. It's not the S and Ku bands that are secured, but rather the data that passes over them. NIST (the National Institute of Standards and Technology, Boulder, Colorado) assembles the FIPS (Federal Information Processing Standards), which are followed for all non-classified government communications.

The DES (Data Encryption Standard) is an older and popularly accepted, encryption standard, which met FIPS requirements. It used a 56-bit key. Then came the Triple DES with a 112-bit key, offering enhanced security. A new standard adopted just a few years ago is the AES (Advanced Encryption Standard), based on the Rijndael algorithm. This standard is the latest direction for cryptography in commercial applications. For everything classified (secret, top secret) the NSA (National Security Agency) at Fort Mead, Maryland is responsible for the security algorithms.

One aspect of DES and AES is what is called symmetric encryption. "You apply the encryption algorithm to your data and then you apply it again to decrypt the data. The symmetric algorithms are very fast. People have demonstrated Rijndael chips that work on gigabit Ethernet connections," says Mark A. Sturza, senior advisor to Wavestream Corporation, 3CsysCo.com. (Wavestream manufactures amplifiers for the Ku and Ka bands, which will replace the current tube amplifiers used by NASA. These amplifiers are used on the ground and in space for transmissions to the shuttle.)

To do symmetric encryption you need to have a single key, which is used at both ends of the communication. Key exchange is done utilizing public key cryptography, making use of the well-known RSA algorithm created by Ron Rivest, Adi Shamir, and Leonard Adelman. There are other methods of key exchange than RSA, but RSA has shown its strength over many years and is known to offer high security.

How Is Shuttle Mission Data Encrypted?
I had assumed that the data sent over NASA's S and Ku band systems during shuttle missions would be protected by one of the secret encryption methods from the NSA. "Actually I sort of doubt that," says Sturza. "It's probably DES or triple DES just because the AES is too new." Cryptography could be "NSA like" for the satellite command-and-control data, which is done with an NSA-approved cryptographic device. "It would be disastrous if high school students could start controlling satellites, especially military satellites," says Sturza.

For something as important as the space shuttle program, the algorithms and/or keys for encryption are probably changed regularly. "I would strongly suspect that they change it on a mission-by-mission basis," says Sturza. It's possible that this is done through hard coding using cryptoloaders such as the NSA uses. These devices are loaded with the keys at a secure location and then taken to the shuttle and plugged in so that the keys can be loaded into the embedded equipment.

Hardware
At the heart of shuttle mission communications is the NSP (Network Signal Processor), which is onboard the shuttle. This device routes and processes all commands, telemetry, and voice between the ground and the orbiter. Any command and voice data that are uplinked to the orbiter, specifically to its S-band PM uplink, or to the Ku-band forward link, are received by the NSP. Not all data is encrypted; data that is encrypted is recognized as such by the NSP and routed to the ComSec (Communications Security) device on the shuttle, where it is decrypted and routed back to the NSP. Data that is to be encrypted before leaving the shuttle is routed to the ComSec and returned to the NSP before being downlinked to the ground.

Differences in Voice and Data Handling
Voice and data are not treated the same throughout the process. When returning voice communications to the ground they are demultiplexed from the command data and converted to analog signals before being routed to the ACCU (Audio Central Control Unit). The command data on the other hand is routed to the GPCs (General Purpose Computers) within the data processing system via the flight forward MDM (multiplexer/demultiplexer).

The NSP digitizes analog voice received from the ACCU. The signal is multiplexed again with the telemetry data from the PCMMU (the pulse code modulation master unit); this multiplexed data is then ready for real-time transmission to the ground. The data is also routed to the operational recorders for archiving. Data is always encrypted at the ComSec before going to the NSP and back to the ground.

Conclusion
Clearly, communicating with the space shuttle is a much more complex proposal than just choosing a radio and talking, but as this series of articles has shown, the more we look into the details of just how the astronauts phone home the more complex it gets, and this is typical of space flight in general. Applications that are trivial in most environments require truly innovative and detailed solutions when exposed to the most hostile of environments. The astronauts' complete reliance on the technology that surrounds them means that every component is mission-critical and every detail needs to be specified and tested beyond what would seem to be common sense requirements.

While this series was in production, the shuttle Columbia was destroyed while re-entering the atmosphere, a tragic reminder of just how complex space technology is, and how easily it can fail. But as I look out my window into the night sky, I'm reminded that somewhere among the stars, one of those grand lights is an International Space Station, a wireless one. It's no longer current to say that we live in a Wireless World. With GPS for Mars coming so quickly, and a space-based Internet already in design, it's time to start talking about our Wireless Solar System.

More Stories By David Geer

David Geer is a contributing writer to WBT, a journalist, and a computer technician. He graduated from Lake Erie College in 1993 with a BA in psychology and has worked in the computer industry and in the media since 1998.

Comments (0)

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


@ThingsExpo Stories
SYS-CON Events announced today that Carbonite will exhibit at SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY. Carbonite protects your entire IT footprint with the right level of protection for each workload, ensuring lower costs and dependable solutions with DoubleTake and Evault.
SYS-CON Events announced today that Progress, a global leader in application development, has been named “Bronze Sponsor” of SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY. Enterprises today are rapidly adopting the cloud, while continuing to retain business-critical/sensitive data inside the firewall. This is creating two separate data silos – one inside the firewall and the other outside the firewall. Cloud ISVs oft...
In his opening keynote at 20th Cloud Expo, Michael Maximilien, Research Scientist, Architect, and Engineer at IBM, will motivate why realizing the full potential of the cloud and social data requires artificial intelligence. By mixing Cloud Foundry and the rich set of Watson services, IBM's Bluemix is the best cloud operating system for enterprises today, providing rapid development and deployment of applications that can take advantage of the rich catalog of Watson services to help drive insigh...
As cloud adoption continues to transform business, today's global enterprises are challenged with managing a growing amount of information living outside of the data center. The rapid adoption of IoT and increasingly mobile workforce are exacerbating the problem. Ensuring secure data sharing and efficient backup poses capacity and bandwidth considerations as well as policy and regulatory compliance issues.
SYS-CON Events announced today that Cloud Academy will exhibit at SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY. Cloud Academy is the industry’s most innovative, vendor-neutral cloud technology training platform. Cloud Academy provides continuous learning solutions for individuals and enterprise teams for Amazon Web Services, Microsoft Azure, Google Cloud Platform, and the most popular cloud computing technologies. Ge...
DevOps at Cloud Expo – being held October 31 - November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA – announces that its Call for Papers is open. Born out of proven success in agile development, cloud computing, and process automation, DevOps is a macro trend you cannot afford to miss. From showcase success stories from early adopters and web-scale businesses, DevOps is expanding to organizations of all sizes, including the world's largest enterprises – and delivering real r...
SYS-CON Events announced today that Outscale will exhibit at SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY. Outscale's technology makes an automated and adaptable Cloud available to businesses, supporting them in the most complex IT projects while controlling their operational aspects. You boost your IT infrastructure's reactivity, with request responses that only take a few seconds.
The 21st International Cloud Expo has announced that its Call for Papers is open. Cloud Expo, to be held October 31 - November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA, brings together Cloud Computing, Big Data, Internet of Things, DevOps, Digital Transformation, Machine Learning and WebRTC to one location. With cloud computing driving a higher percentage of enterprise IT budgets every year, it becomes increasingly important to plant your flag in this fast-expanding busin...
With major technology companies and startups seriously embracing Cloud strategies, now is the perfect time to attend @CloudExpo | @ThingsExpo, June 6-8, 2017, at the Javits Center in New York City, NY and October 31 - November 2, 2017, Santa Clara Convention Center, CA. Learn what is going on, contribute to the discussions, and ensure that your enterprise is on the right path to Digital Transformation.
SYS-CON Events announced today that Interoute has been named “Bronze Sponsor” of SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY. Interoute is the owner operator of Europe's largest network and a global cloud services platform, which encompasses over 70,000 km of lit fiber, 15 data centers, 17 virtual data centers and 33 colocation centers, with connections to 195 additional partner data centers. Our full-service Unifie...
SYS-CON Events announced today that Progress, a global leader in application development, has been named “Bronze Sponsor” of SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY. Enterprises today are rapidly adopting the cloud, while continuing to retain business-critical/sensitive data inside the firewall. This is creating two separate data silos – one inside the firewall and the other outside the firewall. Cloud ISVs ofte...
SYS-CON Events announced today that delaPlex will exhibit at SYS-CON's @ThingsExpo, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY. delaPlex pioneered Software Development as a Service (SDaaS), which provides scalable resources to build, test, and deploy software. It’s a fast and more reliable way to develop a new product or expand your in-house team.
SYS-CON Events announced today that Hitachi Data Systems, a wholly owned subsidiary of Hitachi LTD., will exhibit at SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City. Hitachi Data Systems (HDS) will be featuring the Hitachi Content Platform (HCP) portfolio. This is the industry’s only offering that allows organizations to bring together object storage, file sync and share, cloud storage gateways, and sophisticated search and...
Existing Big Data solutions are mainly focused on the discovery and analysis of data. The solutions are scalable and highly available but tedious when swapping in and swapping out occurs in disarray and thrashing takes place. The resolution for thrashing through machine learning algorithms and support nomenclature is through simple techniques. Organizations that have been collecting large customer data are increasingly seeing the need to use the data for swapping in and out and thrashing occurs ...
A strange thing is happening along the way to the Internet of Things, namely far too many devices to work with and manage. It has become clear that we'll need much higher efficiency user experiences that can allow us to more easily and scalably work with the thousands of devices that will soon be in each of our lives. Enter the conversational interface revolution, combining bots we can literally talk with, gesture to, and even direct with our thoughts, with embedded artificial intelligence, whic...
Detecting internal user threats in the Big Data eco-system is challenging and cumbersome. Many organizations monitor internal usage of the Big Data eco-system using a set of alerts. This is not a scalable process given the increase in the number of alerts with the accelerating growth in data volume and user base. Organizations are increasingly leveraging machine learning to monitor only those data elements that are sensitive and critical, autonomously establish monitoring policies, and to detect...
Internet of @ThingsExpo, taking place October 31 - November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with the 21st International Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world. @ThingsExpo Silicon Valley Call for Papers is now open.
DevOps is often described as a combination of technology and culture. Without both, DevOps isn't complete. However, applying the culture to outdated technology is a recipe for disaster; as response times grow and connections between teams are delayed by technology, the culture will die. A Nutanix Enterprise Cloud has many benefits that provide the needed base for a true DevOps paradigm.
SYS-CON Events announced today that SoftLayer, an IBM Company, has been named “Gold Sponsor” of SYS-CON's 18th Cloud Expo, which will take place on June 7-9, 2016, at the Javits Center in New York, New York. SoftLayer, an IBM Company, provides cloud infrastructure as a service from a growing number of data centers and network points of presence around the world. SoftLayer’s customers range from Web startups to global enterprises.
In his keynote at @ThingsExpo, Chris Matthieu, Director of IoT Engineering at Citrix and co-founder and CTO of Octoblu, focused on building an IoT platform and company. He provided a behind-the-scenes look at Octoblu’s platform, business, and pivots along the way (including the Citrix acquisition of Octoblu).