Project Creation Review: Maple in OpenDaylight Andreas Voellmy, Y. Richard Yang, Xiao Shi, Xin Li, Reinaldo Penno December 18, 2014

What’s the Problem: Challenge of Flow Programming Programming directly against flow tables can be painful: – Limited computational capability: e.g., no logic negation – Lost context: why is this rule here? why is a given rule not there? – Limited action set, e.g., no ARP responses – … 2

Maple: Packet Processing Abstraction User defines a packet processing function, f, in a high-level, general purpose language such as Java. The abstraction: f processes every packet entering the network. f can look at packet fields, query control state, compute a route, send packets, etc. 3

Maple Example Route f(Packet p, Env e) { if (p.tcpDstIs(22)) return nullRoute(); else { Location sloc = e.location(p.ethSrc()); Location dloc = e.location(p.ethDst()); Path path = myShortestPath(e.links(), sloc,dloc); return unicast(sloc,dloc,path); } Does not specify anything on flow tables! Specified in a high-level language with a centralized view. 4

From a Maple Program to Switch Flow Table Rules 5

Maple Compiler and Runtime Key design goals – Language independent core: to support multiple programming languages – Simple, efficient data structures to support correct, optimized rule generations 6

Maple Compiler and Runtime 1. Executes f on an arriving packet, observing traces of data accesses. Observing packet data accesses by asking f to access pkt using libraries Route f(Packet p, Env e) { if (p.tcpDstIs(22)) return nullRoute(); else { if (p.ethDst() == 2) return nullRoute(); Location dloc = e.location(p.ethDst()); Location sloc = e.location(p.ethSrc()); Path path = myShortestPath(e.links(), sloc,dloc); return unicast(sloc,dloc,path); } 7

Maple Compiler and Runtime PrioMatchAction 1tcpDst:22 ToControlle r 0ethDst:2discard 0ethDst:4, ethSrc:6port 30 PrioMatchAction 1tcpDst:22 ToControlle r 0ethDst:2discard 0ethDst:4, ethSrc:6port 30 PrioMatchAction 1tcpDst:22 ToControlle r 0ethDst:2discard 0ethDst:4, ethSrc:6port Executes f on an arriving packet, observing traces of data accesses. 2. Combine traces to form a trace tree (TT), a language-independent, partial decision tree representation of f. 3. Optimizing compiler to compile trace tree to flow tables (FTs) 8

Maple in ODL: A New Programming Model (North Bound Interface) for ODL Programmers A new programming model in ODL so that control programs do not need to generate flow tables directly – Programmers provides Java modules about how they want to treat traffic. – Programmer provides a top-level module defining how multiple modules are composed to determine the overall packet processing function – Example: top-level function calls access control module to determine permit or deny; if deny, drop, else call service chaining module to get next service; if found service, route to it; otherwise … 9

Dependency on ODL Components Use the MD-SAL design Use ODL Flow Manager to program flow- capable devices Need access and modification notifications of ODL managed states (e.g., topology, ports) 10

Deliverables (Scope) of Maple in ODL-Lithium Provide Java-based programming abstraction, comparable to Maple today. Tracing runtime and compiler to target flow- capable devices via MD-SAL. Implement sample applications (e.g., SFC, GBP). API documentation and getting started guide. 11

Committers Andreas Voellmy (Project Lead, Cisco) Reinaldo Penno (Cisco) Xiao Shi (Nominated: Project Contact, Yale U) Xin Li (Nominated: Test Lead, Yale U) Y. Richard Yang (Yale U) 12

Thank you Questions? 13