Question: In a Mission Critical (MC) service using Multimedia Broadcast Multicast Service (MBMS), where does Forward Error Correction (FEC) decoding take place to recover from packet losses, and what is a consequence of adding FEC?
Option 1: FEC decoding occurs at the Base Station (BS), introducing no additional latency.
Option 2: FEC decoding occurs at the MC Service Client, with added latency that is unbounded for mission-critical low-latency requirements.
Option 3: FEC decoding can occur either at the BM-SC or the MC Service Server, depending on the configuration, with significant variable latency.
Option 4: FEC decoding occurs at the MC Service Client, introducing an extra bounded latency to ensure fulfillment of low-latency requirements for mission-critical services.
Explanation: The correct answer is Option 4 because, according to telecommunications principles in mission-critical MBMS services, FEC decoding logically occurs at the receiving end (the MC Service Client) to ensure QoS. Adding FEC introduces latency, but for mission-critical services, this latency must be managed (or bounded) to meet strict low-latency requirements.