Multi-protocol media packaging
Design the packaging/origin layer that takes encoded renditions and serves both HLS and DASH to a fragmented device ecosystem (iOS wants HLS, many TVs/Android want DASH, some need different segment durations), without storing N duplicate copies of the media per protocol. Storage and origin egress are major costs, and a new device family with its own quirks shows up regularly. Design how you store the media and generate the manifests, and how you minimize duplicated bytes.
What a strong answer looks like
Clarify scale and constraints first. Propose a clean component breakdown, then go deep on the hard parts (data model, bottlenecks, consistency, failure modes) and name the trade-offs you are making.
Clarify4:30 left
Estimate4:30 planned
Design13:30 planned
Deep dive10:30 planned
Failure7:00 planned
Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.
Run or narrate your approach, then ask the coach.