NTN latency: delay-tolerant protocols, TCP optimization, buffering

Understanding NTN Latency Components

NTN latency consists of multiple components that together determine the end-to-end user experience. Propagation delay is the dominant factor — a signal traveling to a LEO satellite at 600 km and back takes approximately 4 ms each way, yielding 8 ms round-trip for the space segment alone. Adding gateway-to-satellite feeder link delay, ground network transit, and processing delays at satellite and ground equipment, total one-way latency reaches 25 to 50 ms for LEO and exceeds 300 ms for GEO. When inter-satellite links route traffic across multiple hops, each hop adds another 3 to 5 ms depending…