GPS-Based Timing Isn’t as Reliable as You Think—Here’s What to Do

Global navigation satellite systems (GNSS) play an integral role in our digital lives. Anyone who uses a smartphone for personal navigation is likely familiar with one of these systems, such as the Global Positioning System (GPS) in the U.S. or Galileo in Europe. However, the impact of these satellites extends far beyond navigation. In addition to providing precise positioning data, GNSS signals are a source of precise timing.

A wide range of modern digital applications depend on GNSS timing to work properly, and interruption of these signals can have significant consequences, as highlighted in a recent New York Times article.[1] To name a few examples:

• Manufacturing: Automated systems rely on time synchronization to help them perform operations in the right order. Failure to do so could result in production delays that reverberate throughout the supply chain.
• Financial services: Banks need to keep extremely detailed records of transactions, in the right order and accurate down to the microsecond. Failure to do so could result in stiff penalties from regulators and loss of trust from customers.
• Gaming: Accurate timing is required to execute actions from multiple players in the correct sequence. Without this capability, high-level multiplayer gaming would essentially become impossible.
• Content streaming: Streamers need precise timing to synchronize video and audio feeds. Failure to do so would significantly harm the viewer experience.

Also, there’s the simple fact that enterprises increasingly rely on complex IT infrastructure that’s distributed across the globe. Applications running on this infrastructure need to be able to move data from place to place, while maintaining accurate timing even in the face of latency. Without precise timing, operations could be performed in the wrong sequence, which would make it impossible for these distributed nodes to function as part of a single coherent architecture.

For all these reasons, our lives are very dependent on the precise timing that GNSS satellites provide.

GNSS signals help our digital world run on time

All the satellites that make up a GNSS system must operate in unison to provide accurate positioning information. Therefore, they’re equipped with on-board stable atomic oscillators, whose time is synchronized by official ground stations. Receivers here on Earth can decode GNSS signals to provide precise timing to a variety of digital applications that need it. In turn, this means that if these receivers can’t access GNSS signals for any reason, it could result in major disruption for enterprises and consumers alike.

Because so many applications and systems are dependent on GNSS signals, we’re highly vulnerable to any threats that might stand in the way of GNSS receivers functioning as intended, whether intentional or unintentional. Bad actors have recognized how much our economy and society depend on GNSS timing. They may seek to take advantage of that fact using two different types of attacks:

• Jamming attacks: The attacker interferes with the GNSS signal to stop it from reaching the receiver.
• Spoofing attacks: The attacker broadcasts a fake signal, in an attempt to inject inaccurate timing into a system.

Attackers pursue jamming and spoofing for a variety of reasons—financial, political and personal. Regardless of the motive, enterprises must understand that these attacks can result in massive disruption, including but not limited to the examples mentioned above.

To avoid these challenges, enterprises need a way to access precise timing even when GNSS signals are unavailable or untrustworthy. Equinix Precision Time®—our Time as a Service (TaaS) solution—can provide this capability for our customers.

Equinix Precision Time provides built-in stable timing

In each global market where Equinix Precision Time is generated, there are redundant antennas on the rooftops of separate Equinix IBX® data centers within the market. This means we can continue to receive GNSS timing signals even in the aftermath of a lightning strike or other malfunction affecting a single antenna.

From the antennas, the GNSS signals are routed into our buildings and connected to our own time servers. These servers feature built-in rubidium atomic clocks. After these clocks have been synched to GNSS timing, they’re stable enough to hold the time within 1 microsecond of accuracy for a period of up to 24 hours.

This allows us to take a “trust but verify” approach to using GNSS timing. If we have any reason to doubt the accuracy of the signals we receive, we can simply ignore them and instead rely on our own rubidium clocks. This allows us to continue providing precise timing for our customers until after we’ve confirmed that the GNSS threat has passed.

Thankfully, we haven’t encountered evidence of malicious actors attempting to inject incorrect time into our time servers. However, we have encountered several instances of GNSS interference, each of which lasted for several hours. Thanks to our GNSS threat mitigation capabilities, we were able to ensure this jamming didn’t have an adverse effect on our stable time base.

Delivering stable timing to the world with Equinix Fabric

We generate our time base the same way in each market, using the same GNSS signals. This means all our locations are synchronized with one another. We then use our time base to generate individual timing services for our customers.

We deliver these timing protocol packets wherever they’re needed using Equinix Fabric®, our dedicated virtual networking solution. The combined capabilities of Equinix Precision Time and Equinix Fabric allow our customers to synchronize their devices to within 50 microseconds of UTC, no matter where those devices are within the region.

Customers can also use the Equinix service architecture to ensure geo-redundant timing. They can order timing services from multiple Equinix locations, connected by Equinix Fabric, and feel confident that each of their services will be within 50 microseconds of UTC. If the service is ever unavailable in a location for any reason, the customer can rely on the other location as a backup.

In addition, the integration between Equinix Precision Time and Equinix Fabric makes it quick and easy for businesses to start accessing the precise timing they need. Current Equinix Fabric customers can order timing services directly from the same self-service portal they’re already familiar with, instead of having to access a separate portal. Watch the video below for a look at how simple it can be to access Equinix Precision Time via the Equinix Fabric portal:

Whether it’s mitigating GNSS threats or delivering stable, accurate time to locations around the world, Equinix Precision Time is the end-to-end solution that enterprises need to stay in sync with our digital world.

To learn more, read our solution brief Why network time synchronization is critical for enterprise and cloud infrastructure.

[1] Selam Gebrekidan, John Liu and Chris Buckley, One Satellite Signal Rules Modern Life. What if Someone Knocks It Out? The New York Times, March 28, 2024.