The dynamics of video networking solutions have changed significantly in recent years thanks to two key factors.
Network heterogeneity: Coexistence of traditional Ethernet with pervasive wireless technologies like Wi-Fi.
Device heterogeneity: Rise of multiple types of networked devices that exchange media and information – desktop, embedded, and mobile that includes laptops, smartphones and tablets.
Given this context, streaming servers, transcoders, and network cameras or DVRs need to overcome several challenges to enable quality video streaming to embedded/mobile clients over wireless networks.
Challenges in Video Streaming Over Wireless Networks
Take a look at some of the main concerns around video streaming over wireless networks.
Wi-Fi networks offer lower bandwidth (theoretical maximum of 900Mbps for 802.11ac, <50% of that practically achievable) as compared to wired networks (1000Mbps for GbE).
Wireless applications are sometimes unable to utilize the maximum available bandwidth due to channel utilization by other users and re-transmissions.
Interference from other wireless devices affects the signal quality and prevents such networks from achieving their full capacity.
The key impact is in terms of increased packet loss and hence higher re-transmissions.
Variable Channel Conditions
Mobility increases the variations in channel and signal conditions between the transmitter and receiver.
Signal strength in relation to distance between the transmitter and receiver is subjected to inverse-square law (Eg: If distance grows by 2x, the signal strength drops by 4x). This affects the available bandwidth and eventually the achievable video quality.
So how do we tackle these challenges to drive seamless video streaming over wireless networks? By carefully addressing the following three key aspects.
1. Network Aware Encoding and Rate Control
Improve error resilience and lower latency with sub-frame video processing.