Improving network availability with Precision Path

A little over a year ago, we introduced fast path failover technology as a way to improve connectivity for users requesting content from Fastly’s edge cloud platform. Today, we’re adding to that solution with technology that focuses on improving performance across internet paths between your origin server and the Fastly network. 

Together, the improvements Precision Path brings now span the connections between the user and Fastly and the origin and Fastly. Deployed across the entire Fastly platform for all customers, Precision Path provides: 

• Improved protection from transient provider issues for origin server requests, and

• A more robust delivery of content to your end users. 

Best of all, Precision Path provides self-healing, fully automated, real-time fault detection and mitigation for all traffic on Fastly’s network. It doesn’t fix every problem, but it’s getting us a lot closer to that vision. 

Here’s how it works.

The challenge: bad internet weather days

Internet outages come in many sizes. Some are large enough to generate global attention, but often, they’re events that pass quickly yet still cause performance degradation along the way. This can impact the ability of Fastly — or any content delivery provider — to access a customer’s origin services for new or updated content when needed. And this, in turn, can result in 5xx HTTP server errors for end users.  

On any given day, internet transit providers throughout the world collectively experience anywhere from a few to hundreds of these temporary, short-lived, connectivity or performance degradations, often referred to as “internet weather.” Based on analysis of traffic on our worldwide network, we estimate that a substantial portion of origin fetch errors that end up getting served to end users are due to these transient carrier issues occurring between us and our customers’ origin(s). Current industry techniques, like BGP routing changes, are often too large a hammer to solve these smaller outages, and the issues pass before the BGP changes have even been propagated.

The solution: Precision Path to the rescue

With Precision Path, Fastly can now automatically detect and route around origin connection issues in real time to noticeably reduce errors and improve end user experience. As of today, Precision Path is included as part of our delivery platform for all customers. 

So how does it work? Precision Path addresses transient path degradation by:

• Detecting origin connection problems,

• Triggering real-time mitigation tools, like automatic carrier re-routing to impacted origins, and 

• Giving you timely visibility into these events and the results of our mitigations.

More specifically, Precision Path is now always monitoring all origin connections in every Fastly PoP worldwide. When it detects an underperforming origin connection, it will automatically identify all possible alternative paths to that impacted origin and re-route the connection to the best alternative. This all occurs in real time, often allowing us to re-establish a healthy origin connection before 5xx errors get served to end users. 

If we picture internet delivery as being like a traditional supply chain, Precision Path's fast path rerouting is like using road navigation software that redirects you around traffic congestion on the highway to ensure you remain on the best possible route to your destination (solving edge-to-user congestion). Precision Path's new origin connection rerouting is like opening up a loading dock on an alternate highway at your shipping facility (PoP).

Precision Path ensures end-to-end automated selection of the best performing internet paths to deliver content from your origin servers through to your users. We’ve been testing this new technology since March 2020, and we’ve seen some pretty impressive results around recent provider-specific network events, with significant volumes of traffic at impacted data centers shifting to alternative paths during one recent short-lived outage we observed affecting one of our providers. While Precision Path doesn’t resolve every issue, we are pleased to be incrementally improving reliability and performance beyond the edge of our infrastructure for our customers.

Want to check it out for yourself? Sign up for Fastly today.