1. Rob Sherwood Big Switch Networks Ethernet Technology Summit 2014
Open SDN Switch OS
Rob Sherwood
Big Switch Networks
Ethernet Technology Summit 2014
Santa Clara, CA USA
April-May 2014

2. Rob Sherwood CTO, Software architect at Big Switch Networks
ONF: former chair of ArchWG and vice-chair of TestingWG
Working in OpenFlow/SDN since 2008
Wrote the FlowVisor:
Santa Clara, CA USA
April-May 2014

3. Outline Motivation: Open Networking SDN Basics Switch Software
Open Network Linux
OF-DPA
Conclusions and Community

4. SDN Architectural Evolution
BEFORE
NOW
Automation Tool
Network HW
SDN App
SDN Controller
(Thin) SDN OS
Automation Tool
OpenFlow
&
Extensions
North-bound
APIs
SDN SW solution from single vendor
Exactly like the hypervisor/server model
Full access to switch ASIC
Accelerate HW/SW disaggregation
APIs
SDN App
North-bound
APIs
SDN Controller
CP/DP
Separation
OpenFlow
is just API
OpenFlow
Network HW
(Thick) NetOS OF
Too many moving parts (multiple SDN SW vendors)
OF agent SW from HW vendor!
Limited access to switch ASIC access

5. SDN Architectural Evolution
Automation Tool
Big Tap
Cloud
Fabric
Big Switch Network’s Commercial Products
SDN App
SDN Controller
This talk:
Open Source
Switch OS
Network HW
(Thin) SDN OS
©2014 BIG SWITCH NETWORKS, INC PROPRIETARY AND CONFIDENTIAL

6. Isn’t Networking already open?
All Hardware Specs Public
X86 Servers
Binary SDK
for Packet Forwarding
NPU, FPGA, SoC
 Open
Closed OS, Open Control Plane APIs
DC – 1U
ToRs, Spines
Closed OS,
Open APIs for Policy, Stats
Multi-chassis Routers
10 Gb/s
100 Gb/s
1 Tb/s
10 Tb/s
Aggregate Throughput 

7. Isn’t Networking already open?
All Hardware Specs Public
X86 Servers
This talk
Binary SDK
for Packet Forwarding
NPU, FPGA, SoC
DC – 1U
ToRs, Spines
 Open
DC – 1U
ToRs, Spines
Closed OS, Open Control Plane APIs
Closed OS,
Open APIs for Policy, Stats
Multi-chassis Routers
10 Gb/s
100 Gb/s
1 Tb/s
10 Tb/s
Aggregate Throughput 

8. These designs are fundamentally the same!
Goal: One Big Switch
Spine
Leaf
Leaf-Spine
Fabric
Controller 2
Controller 1
Chassis-based Fabric
Fabric Backplane
Supervisor 2
Line Card
Supervisor 1 1 2 3 4 5 6
These designs are fundamentally the same! 8

9. Forwarding Abstraction: Flow Table
Priority
Match
Action List
500
IP.proto=6
TCP.dst=22
TTL--,
Fwd:port 3
200
IP.dst=
128.8/16
Queue: 4
100 *
DROP
Flow Table
Flow Table
Flow Table
“Assembly Language of Networking”
Too low-level for most operators
Active work in the Open Networking Foundation to bring OpenFlow to feature parity with “closed flow”

10. Switch Scaling: Understanding Tables
Classical OpenFlow versus Modern
Proactive and Multi-table OpenFlow
Processing
Pipeline
VLAN
Table
L2 Table:
100K+
Entries
L3 Table:
Egress Table
Our Modern OpenFlow implementation leverages all tables
Scales like traditional
Allows proactive population
Proactive reduces controller load and allows for headless control
Early OpenFlow implementations only used the most flexible table.
Didn’t scale well
Scale forced reactive population
Reactive caused controller load and addition scale problems
ROB AND Blog Me!
ACL Table:
~2k Entries
OpenFlow does NOT imply Flow-based Networking

11. OUtline Motivation: Open Networking SDN Basics Switch Software
Open Network Linux
OF-DPA
Conclusions and Community

12. Switch Light Architecture
Big Network
Controllers
Legend
Open
Network
Linux
CLI
OpenFlow
Agent
Switch Light OS
Indigo
Loxi
BSN Open
ZTN
Loader
SSH
Fan
Control
NTP
Syslog
SNMP
Indigo/ASIC Driver
BSN Closed
LibC on Debian Wheezy Base Distribution
ASIC SDK
ONL Linux Kernel
I2C
GPIO
Device
Trees
ASIC
3rd Party
Closed
Source
Switch Light is our Indigo OpenFlow Agent running on Open Network Linux on x86 or ASIC-based hardware.

13. Open Network Linux A Linux distribution for bare metal switches
Open-sourced commercial code, build scripts, drivers from Switch Light
Part of Open Compute Project (OCP)
Project goals:
Improve perception/de-risk bare metal
“Crowd source” larger Switch Light HCL
Released mid-January: Initial results
Strong community response from ODMs, OCP
Accton self-supporting three new boxes, more ODMs interested
Other vendors investigating ONL for their own purposes
Info: – under construction

14. ONL – Supported Hardware
ONL Support is Pre-cursor to Switch Light Support
Working on OCP box from Interface Masters with x86 support

15. OpenFlow Datapath Abtraction: OF-DPA
Indigo
open
driver
OF-DPA API
OF-DPA
closed
SDK
Chip
Ethernet Technology Summit
Santa Clara, CA USA

16. Conclusion and Community
Many Open Source projects
Take the pieces or the whole: ONL
Didn’t have time: Indigo and Loxi
All of these projects are used by BSN
Quality, tested code
“Productized” modern OpenFlow
Join at: opennetlinux.org/community
Comments and feedback welcome