DistOS 2014W Lecture 19

* Dynamo

• Key value-store.

-*Build a distributed storage system:

• Scale
• Simple: key-value
• Highly available
• Guarantee Service Level Agreements (SLA).
• high concurrent.
• no dynamic routing.
• 0-hop DHT: means it is doe not have information when deliver packet from node to another , it has direct link to the destination
• Dynamo sacrifices consistency under certain failure scenarios.
• it has partition algorithm.
• Consistent hashing: the output range of a hash function is treated as a fixed circular space or “ring”.
• Key is linear and the nodes is partition.
• ”Virtual Nodes”: Each node can be responsible for more than one virtual node.
• Each data item is replicated at N hosts.
• “preference list”: The list of nodes that is responsible for storing a particular key.