1.
DataStax Advanced Replication
Brian Hess
Sr. Product Manager, Analytics

2.
Why Advanced Replication
• Standard Cassandra replication has its limits
• Lots of disconnected “edge” nodes/data centers/clusters
• Replicating to central “mother ship” for aggregating
• Inconsistent connectivity
• All data centers are read-write – no read-only DCs
2© 2016 DataStax, All Rights Reserved.

3.
What is Advanced Replication
• Advanced Replication supports:
• Many edge clusters replicating to a central hub
• Consistent or sporadic connectivity – “store and forward”
• Prioritized streams for limited bandwidth situations
• One-way replication
• Active queries at the edge, as well as replicating to the hub
• Search/Analytics supported at edge and hub clusters
3© 2016 DataStax, All Rights Reserved.

4.
Company Confidential
“What was Brian’s
average purchase
per store this
week?”
Analytics Over
All Data
“What did Brian buy
today across all
stores?”
Can Query
Global Sales
“What was the
hottest product
here this week?”
Analytics of
Local Sales
“What did Brian buy
here today?”
Can Query
Local Sales
Each Store Central Hub
Example: Retail Sales
© 2016 DataStax, All Rights Reserved.

5.
Company Confidential
Key Verticals
© 2016 DataStax, All Rights Reserved.

6.
Architecture – Edge View
6
Client
Edge
Replication
Log
Collection
Agent Table
Replication
Agent
Hub Cluster
Table
© 2016 DataStax, All Rights Reserved.

7.
Architecture – Edge View
7
Client
Edge
Replication
Log
Collection
Agent Table
Replication
Agent
Hub Cluster
Table
Normal CQL
Operation
CQL Trigger
captures
mutation
Maintained in C*
table for Fault
Tolerance
Pulls from
Replication Log in
priority/time order
Replicates to
Hub via normal
CQL driver
High Priority mutations
opportunistically sent to
Hub asynchronously
© 2016 DataStax, All Rights Reserved.

8.
Topology
8© 2016 DataStax, All Rights Reserved.