The Power of AL-FEC - Stats and Savings

Applying the Highest Level

To understand the differences between types of FEC we need to understand a little about how the Internet protocol suite, commonly known as TCP/ IP, defines the communications protocols used to send data. TCP/ IP specifies how data should be packetized, addressed, transmitted, routed and received. This functionality is organized into four (or more) levels or layers:

1. The Application level (provides protocols that allow software to send and receive information, such as via web browsers end email clients)

2. The Transport level (where large files are broken into smaller groups for sending),

3. The Internet level (providing addressing for connections between independent networks) and

4. The Link level (providing a physical connection between devices)

Regular FEC methods (think Reed-Solomon, Viterbi, and even LDPC) work at the Link level (LL) restricting them to checking for and correcting errors in data transferred between network entities at this same level. Such FEC is unaware of the wider application and is restricted to a local area network boundary. It can only correct errors in data transferred within this boundary, such as audio and video packages, over tiny timeframes.  LL-FEC mitigates bit errors that occur over short time intervals (e.g., brief signal fades or bursts of interference). Accordingly, when downlinks are interrupted, data bits are lost, and LL-FEC cannot request missing parts to repair a file. The result is a broken package that needs resending and retransmitting to every receiver, creating delays and unnecessary costs.

Advanced FEC operates at the Application level (AL). This is where file sizes are largest, the time of transmission is longest and the need for error correction is greatest. It is also where cross-boundary and more advanced behaviors occur. As a result, they can check for errors, repair data, and request retransmissions across different levels. AL-FEC is aware and unrestricted, checking for errors and repairing data across different levels. This removes the need for retransmissions.

Accordingly, AL-FEC is the highest level FEC and ensures the greatest efficiency, reliability, operational effectiveness and cost savings.

The Results: Performance You Can Count On and the New Standard for Delivery

The charts above highlight how KenCast’s AL-FEC technology dramatically improves both speed and efficiency in delivering large files over unreliable or congested networks. In a simulated 50 Mbps wireless scenario, a 100MB mission-critical file reaches 1,000 recipients in just 17 seconds using Fazzt — compared to 32 to 79 seconds using conventional methods, depending on packet loss.

While traditional “Spray & Pray” approaches flood the network with repeated copies of data—hoping enough packets arrive intact—this brute-force method becomes increasingly inefficient as packet loss or the number of recipients rises, consuming excessive bandwidth to maintain reliability. In contrast, our Application Layer FEC (AL-FEC) maintains a consistent, minimal data footprint regardless of network conditions. This efficiency scales dramatically: when delivering a 10GB file to one million recipients, AL-FEC uses just a fraction of the data required by conventional methods. It enables seamless handoffs, reduces network strain, and ensures faster, more reliable delivery—even in environments where timing can be the difference between success and failure.

The Power of AL-FEC: Performance That Pays Off

These charts illustrate the dramatic bandwidth savings achieved using AL-FEC (via KenCast's Fazzt) compared to traditional delivery methods. On the left, when sending a 1GB file to 1,000 recipients without requiring a return link, Fazzt uses just a fraction of the bandwidth required by the one-way “Spray & Pray” approach — a 73.22% reduction, translating to an estimated $732,200 in annual savings based on full transponder use.

On the right, even when comparing against the more efficient but two-way “Divide & Conquer” method (which relies on backchannel acknowledgments), Fazzt still delivers with 60.17% less bandwidth, saving approximately $601,700 per year.

The reason is clear: while legacy methods either flood the network with repeated data or require frequent status reporting from all receivers, AL-FEC enables precise, forward-only correction without retransmissions. The result is minimal data overhead with maximum reliability, even at a 0.1% loss rate, making it ideal for high-stakes, bandwidth-sensitive scenarios.

Many customers do not know they are using the lesser form, believing all FEC to be the same.  You would be smart not to make that error. Please check that the FEC your organization is using is AL-FEC if you are multicasting.