SDN Programming

Question 1

SDN Workflow

Answer 1

Read/Monitor State
Compute Policy (decision plane)
Write Policy

Question 2

SDN Read problem solutions

Answer 2

Predicates (and/not primitives to build complex rules)
Rule unfolding
Packet suppression (Limit (1) )

Question 3

SDN Write problem solutions

Answer 3

Atomic Commits

Copy packets, only apply updated policy once all old policies are removed

Question 4

Virtual Networking Benefits

Answer 4

Allows implementation of different networks without having to replace physical infrastructure

Question 5

SDN vs Network Virtualization

Answer 5

SDNs seperate control and data planes

NV seperates logical and physical planes

(SDN does not abstract underlying network)

Question 6

Frenetic Language

Answer 6

SQL like language to select packets

Question 7

SDN Policy Composition

Answer 7

Parallel
Count and Forward

Sequence
Firewall then Switch

Question 8

Why use API

Answer 8

high level abstraction

Question 9

Pyretic function - flood()

Answer 9

return one packet per local port

Question 10

Pyretic function match(f=v)

Answer 10

match any packet where key f is assigned value v

Question 11

Pyretic sequential composition

Answer 11

match(a)&raquo_space; fwd(12)
» operator
execute left side, then right side