BeHop : SDN for Dense WiFi Networks

Yiannis Yiakoumis Manu Bansal, Sachin Katti, Johan van Reijendam, Nick McKeown

Stanford University

Deployment 150

(user,chaotic)

Configuration user

Access own AP

• 27M (24%) US Households in MultiUnit Structures • ~25 neighboring AP (@ Mission SF)

Common wireless issues

• High interference - Congested channels

• Poor coverage – channel degradation

• Misconfiguration

• Poor channel and power allocation

Lack of co-ordination among individual home networks

BeHop

Question : How should we design such dense networks? Hypothesis : SDN-based coordination can help

Provide users with fast, reliable, and personalized service

Goal

BeHop

Provide users with fast, reliable, and personalized service

Goal

Question : How should we design such dense networks? Hypothesis : SDN-based coordination can help

• Allow personalized user configuration

– name, password, policies

• Simplify and improve network management

– infrastructure visibility and control

– use global perspective

– physical infrastructure for high performance • overprovision, better coverage, redundancy

• decouple deployment from operation

Deployment 150

(user,chaotic) 150

Configuration user user+infra

Access own AP infra

WiFi Virtualization

On a virtualized WiFi architecture

the user sees a single, personal AP that follows him wherever he goes

WiFi Virtualization

WiFi Virtualization

WiFi Virtualization

WiFi Virtualization

• Expose Configuration for users (e.g. SSID, password, policies) • Personalized view of the network that follows the user • Hides wireless complexity from client

• which channel/AP to use • when to handoff

• Allows the infrastructure to optimize based on global knowledge

Stanford BeHop Experiment • Stanford’s grad housing building ( 150 studios)

• Netgear AP (OpenWrt + Openvswitch)

• SDN WiFi extensions

-> Performance – Band Steering / Load Balancing

– Green-Field vs backward compatibility

– Mobility

– Turn-off redundant AP

-> User Policies – Personal SSID

– Personal firewall

– Premium Video Service

Conclusions

• Dense WiFi networks are commonplace

• Coordination can improve user experience and performance

• WiFi Virtualization

– A personal network that follows me

– Easy to manage and control the infrastructure

• Stay tuned for results…

thanks (yiannisy@stanford.edu)