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OSPF Offloading: The HELLO Protocol. A First Step Toward Distributed Heterogeneous Offloading Speaker: Mary Bond. Introduction: The Challenge. Traditional IP router architecture incorporates single centralized control processor Scalability issues are real
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OSPF Offloading: The HELLO Protocol A First Step Toward Distributed Heterogeneous Offloading Speaker: Mary Bond
Introduction: The Challenge • Traditional IP router architecture incorporates single centralized control processor • Scalability issues are real • Large amount of I/O bandwidth required across backplane
The Protocol Offload Solution: Long Term Goal • Distribute functionality by protocol offloading to forwarding plane blades • Design a generalized framework for offloading protocols • The Approach: • Examine offloading possibilities of many routing protocols • Use collective results to design offloading framework
OSPF: A Brief Overview • Link state vector algorithm • Distribute data by flooding • Amount of data passed reduced via area grouping • External data advertised, separate from link state data
OSPF: A Brief Overview • HELLO packets used to acquire neighbors • HELLO protocol elects designated router • Link state ads (LSAs) reflect adjacencies • LSAs flooded reliably • Link state database is collection of LSAs from every router in area
OSPF Offloading: The HELLO Protocol • Two primary OSPF data structures: • Interfaces • Neighbors • Interface algorithms: • HELLO • Designated Router Election • Neighbor algorithms: • Database Distribution • Link State Updates • Routing Table Calculation
Communication Between GOSPF and OOSPF • Synchronizing Data Structure Fields • Starting/Stopping HELLO Timers • Instigating FSM Transitions • Triggering Link State Advertisements • Updating Designated Router (or Backup) • Instigating sending of HELLO Packets
GOSPF and OOSPF Proxies • GOSPF and OOSPF communicate via proxies • Remote procedure calls are transparent • TCP connection
The RPC Class • Provides general framework for communication between proxies • Child classes inherit from RPC class, one for each remote procedure call • Child classes correspond to specific functions (called remotely) between GOSPF and OOSPF
Conclusions • Future control plane processing presents a bottleneck issue • Protocol offloading is a possible solution • This project was a first step toward studying the offloading of control plane routing protocols.