Replication
Replication can mask network problems.
- Example: A tool against denial of service.
Questions:
- How many replicas do we need? (dynamic).
- Where do we place them? (dynamic).
- Which replication method to use? (primary backup, anti-entropy, peer (active) replication).
Tradeoffs – more replicas means:
- Lower communication cost for access, lower connectivity requirements.
- Higher costs for updates, higher space requirements.
- Calls for the Cost-Benefit Framework.