Our paper titled “ESPRES: Transparent SDN Update Scheduling” will appear at HotSDN 2014 in Chicago. Peter Peresini will present the work. Here is the abstract:
Network forwarding state undergoes frequent changes, in batches of forwarding
rule modifications at multiple switches. Installing or modifying a large number
of rules is time consuming given the performance limits of current programmable
switches, which are also due to economical factors in addition to technological
ones.
In this paper, we observe that a large network-state update typically consists
of a set of sub-updates that are independent of one another w.r.t. the traffic
they affect, and hence sub-updates can be installed in parallel, in any order.
Leveraging this observation, we treat update installation as a scheduling
problem and design ESPRES, a runtime mechanism that rate-limits and reorders
updates to fully utilize processing capacities of switches without overloading
them. Our early results show that compared to using no scheduler, our schemes
yield 2.17-3.88 times quicker sub-update completion time for 20th percentile of
sub-updates and 1.27-1.57 times quicker for 50th percentile.