Orca: Server-assisted Multicast for Datacenter Networks

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" summary

Orca claims a practical multicast primitive for datacenters that splits forwarding work between switches and servers, implements a controller plus per-rack Orca agent, and runs on a testbed and large simulation. It builds label formats that are fixed-size (about 19 bytes fixed label), pushes leaf label resolution to servers, and replicates tiny per-rack state for fault tolerance. Evaluation on a 27,648-host simulation with 1M sessions and a testbed shows reduces switch state by up to two orders of magnitude and zero redundant traffic.

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" chapters (17)

1. 0:00Intro
2. 0:36Group Communication in Datacenters
3. 1:48Multicast in Datacenter Networks Can benefit from multicast
4. 3:03Challenges of Multicast Forwarding in DCNS Large-scale multi-tenant environmen
5. 4:57Our Goal
6. 7:30Our Approach
7. 7:54Orca Labels
8. 8:44Orca: Leaf Labels • Leaf switch forwards multicast packets to Orca Agent
9. 9:15Orca: Source Label
10. 10:30Orca Architecture
11. 11:49Fault-tolerant Forwarding
12. 12:53Evaluation using Simulations A Leaf-spine topology with 27K hosts
13. 13:50Orca vs Elmo
14. 15:46Evaluation in a Testbed
15. 16:00Benefits of Orca to Applications
16. 17:21Agent Scalability
17. 17:47Conclusions Orca is an efficient multicast system for DCNS • The key idea is to move parts of forwarding to servers

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