What is SRTLA? The Complete Guide to SRTLA Bonding (2026)

Outdoor live streaming is notorious for sudden disconnections. A streamer turns a street corner, enters a crowded cafe, or transitions from WiFi to mobile data, and the stream freezes. SRTLA was designed specifically to eliminate this problem by bonding multiple network connections into one unbreakable video pipeline. Here is how it works under the hood.

What does SRTLA stand for?

SRTLA stands for Secure Reliable Transport Link Aggregation. It takes the battle-tested SRT streaming protocol (which operates over UDP with packet retransmission and encryption) and adds a multiplexing layer on top. Instead of sending all your video data down a single network pipe, SRTLA splits packets across every active network interface simultaneously.

How SRTLA bonding actually works

• ▸Link Discovery: The sender (e.g. Moblin, IRL Pro, Belabox) detects all connected network interfaces: SIM 1, SIM 2, and WiFi.
• ▸Packet Distribution: Video frames are broken into small UDP packets and dynamically scheduled across links according to their instantaneous bandwidth and latency.
• ▸Receiver Reassembly: A managed SRTLA relay server receives packets from all paths, reorders them, handles retransmission requests (ARQ), and outputs a pristine, continuous SRT stream to OBS.
• ▸Seamless Failover: If your WiFi drops out or a cellular tower congests, the relay seamlessly shifts traffic to the surviving links without dropping a single frame.

SRTLA vs Standard SRT: The Critical Difference

Standard SRT is exceptional at recovering lost packets on a single noisy connection, but it cannot aggregate bandwidth or survive a total connection drop. If your phone loses its 4G link, standard SRT dies. SRTLA solves this by maintaining independent parallel communication channels. Even if one network completely disconnects, your stream remains uninterrupted.

What hardware and apps support SRTLA?

• ▸iOS: Moblin (free on App Store, native SRTLA support with dual SIM or SIM + WiFi).
• ▸Android: IRL Pro (native SRTLA bonding mode with dual SIM).
• ▸Dedicated Encoders: BELABOX encoders (Raspberry Pi / Jetson with multiple USB 4G/5G modems).
• ▸Receivers: Managed cloud relays like PerHost, or self-hosted BELABOX receivers.