Towards a dynamic multi-cloud computing universe Divy Agrawal & Amr El Abbadi UC Santa Barbara

Origins of Cloud Single data center Focus: – Virtualization technologies – Reliable and robust infrastructure What if the data center fails? Source: center-cisco-free-twice-as-efficient/

Cloud Evolution Multiple static data centers Geo-replication – Fault-tolerance – Lower latency across regions What are we missing? Source: content/uploads/2009/08/multi_master_replication2.jpg

Cloud Evolution Too many providers – Potential for vendor lock-in – Lack of cloud standards Focus only on large “cores” – Missing out on resources at the edge Source: Source:

Cloud Revolution Build a cloud ecosystem: Lots of resources at the edge – Content Delivery Networks Huge potential with transient resources – Wall street companies – Large infrastructures with diurnal usage Inter-operability between cloud providers

Dynamic Clouds (diurnal behavior) 1:00 am 9:00 am Transition through time epochs Nucleus

Research Vision Design Principles: – Separate system and application data – Decouple control from storage of date A collection of static cloud “nucleus” – Heart and mind: coordinate and synchronize. A collection of dynamic cloud “cores” – Augment system capacity.

Technical Challenges A uniform namespace for multi cloud cores. Efficient integration of surplus capacity. Effective load and data migration. Scalable monitoring and system modeling.

Agility and Elasticity Managing Churn – Predictable; checkpoints. Load balancing and elasticity – Migration; replication Data Placement – Need models to account for churn and load changes.

Building a Dynamic Cloud System Monitoring and Control – System stats, failures, data placement, etc Metadata Management (system state) – Strong consistency within a single core – Casual consistency across cores (dist dictionary)? Data Access Control – Inexpensive tenant migration Data Storage (fault tolerance) – Cross core replication—timeline consistency?

More Issues Standards Differential pricing: varying demand and availability SLAs versus Operating cost Privacy and security Supporting diverse applications and workloads