Mesh Networking:Building, managing, and the worksMesh Networking:Building, managing, and the works

Suman BanerjeeSuman Banerjee

Wisconsin Wireless and NetworkinG Systems (WiNGS) Laboratory

Mesh in the pressMesh in the press

Outdoor metro meshesMany cities, urban downtowns

A set of mesh points connected to gateways

Goal: provide Internet access to users

Business model?Serve the taxpayer

Run it as an ISP

Single “expert” administrator of the network, and homogenous nodes

But there are other scenarios!

Outdoor metro meshesMany cities, urban downtowns

A set of mesh points connected to gateways

Goal: provide Internet access to users

Business model?Serve the taxpayer

Run it as an ISP

Single “expert” administrator of the network, and homogenous nodes

But there are other scenarios! Madison, WI downtown60 mesh points

Scenarios I want to talk aboutScenarios I want to talk about

Rural networkingAn urban hub connecting a set of villages (say 40 mile range)Goal: provide Internet access to usersIntegrate applications: Distance education, tele-medicine, expert adviceCost needs to be low“Not-so-expert” administrator, possibly homogeneous nodes

Indoor (home) meshesExtend the notion of home-networking

HDTV over wireless: from set-top box to 2nd floor TVPhone base unit to handset in kitchen

Single “not-so-expert” administrator, heterogeneous nodes

Rural networkingAn urban hub connecting a set of villages (say 40 mile range)Goal: provide Internet access to usersIntegrate applications: Distance education, tele-medicine, expert adviceCost needs to be low“Not-so-expert” administrator, possibly homogeneous nodes

Indoor (home) meshesExtend the notion of home-networking

HDTV over wireless: from set-top box to 2nd floor TVPhone base unit to handset in kitchen

Single “not-so-expert” administrator, heterogeneous nodes

Rural networking: IssuesRural networking: Issues

Why meshes make sense?Can use WiFi (unlicensed)

Most of equipment is low cost and widely available

Technology is getting there to meet the demands

Why meshes make sense?Can use WiFi (unlicensed)

Most of equipment is low cost and widely available

Technology is getting there to meet the demands

Rural networking: IssuesRural networking: Issues

Start at the very beginningHow do we deploy a mesh?

ManageHow do we monitor and manage it?

ImproveIf we detect performance problems, what are the right changes to make?

SecurityA perennial problem in any domain

Start at the very beginningHow do we deploy a mesh?

ManageHow do we monitor and manage it?

ImproveIf we detect performance problems, what are the right changes to make?

SecurityA perennial problem in any domain

DeploymentDeployment

Where to place the mesh nodes + how many nodes

such that:Budget constraints are metGood fault tolerance and quality of service

40 km

• 384 Kbps to each village• Also multicast

DeploymentDeployment

Parameter choices:Many possible locations (> few 100s)

Candidates for deploying mesh nodes

Directional nodes vs. omni-directional nodesCost vary depending on nature of antenna systems in use

Interference patternsBuildings, other hotspots

Gateway locations

Choice of channels in multi-radio nodes

Parameter choices:Many possible locations (> few 100s)

Candidates for deploying mesh nodes

Directional nodes vs. omni-directional nodesCost vary depending on nature of antenna systems in use

Interference patternsBuildings, other hotspots

Gateway locations

Choice of channels in multi-radio nodes

DeploymentDeployment

Current state-of-the-art:

Manual inspection based human judgement

Example : MadCity broadband uses consultants

WFI Networks

Neither cost effective nor scalable

Current state-of-the-art:

Manual inspection based human judgement

Example : MadCity broadband uses consultants

WFI Networks

Neither cost effective nor scalable

ManagementManagement

All of the network management headaches that occur in enterprise

PlusThose due to multi-hop wireless nature of the network

A control wired backplane does not existControl and data on the same “flaky” wireless interface

Performance debuggingUser calls up:

“Network is too slow at University Ave. and Randall St.”

Can we find the bottlenecks?Can we detect route mis-configurations?

All of the network management headaches that occur in enterprise

PlusThose due to multi-hop wireless nature of the network

A control wired backplane does not existControl and data on the same “flaky” wireless interface

Performance debuggingUser calls up:

“Network is too slow at University Ave. and Randall St.”

Can we find the bottlenecks?Can we detect route mis-configurations?

ManagementManagement

Current solutions:Very basic, SNMP based

Essentially monitoring done by the mesh nodes themselves

Can be extremely inaccurate

Data is of low fidelity

Maybe a specialized (low-cost) monitoring infrastructure

Current solutions:Very basic, SNMP based

Essentially monitoring done by the mesh nodes themselves

Can be extremely inaccurate

Data is of low fidelity

Maybe a specialized (low-cost) monitoring infrastructure

ImproveImprove

How to upgrade the network?Where do we deploy new nodes?

It is possible to spend money and degrade performance

How many nodes?

What kind of nodes?

Where do we place them?

How to upgrade the network?Where do we deploy new nodes?

It is possible to spend money and degrade performance

How many nodes?

What kind of nodes?

Where do we place them?

SecuritySecurity

Current planned modelSecure each link

End-to-end security obtained through composition of secure links

What if a mesh node is compromised?

Current planned modelSecure each link

End-to-end security obtained through composition of secure links

What if a mesh node is compromised?

Indoor meshes: IssuesIndoor meshes: Issues

Devices manufactured by different vendors

TVs, set-top boxes, phones/handsets, etc.

Interoperability is key

Should be virtually un-managedThings should just work out of the box!

Security

Devices manufactured by different vendors

TVs, set-top boxes, phones/handsets, etc.

Interoperability is key

Should be virtually un-managedThings should just work out of the box!

Security

Finally, the applicationsFinally, the applications

Multi-hop wireless has many interactions that reduce end-to-end throughput

HDTV, voice, tele-medicine requires some QoS guarantees

Wireless links are very diverse and have different properties

Some of the MAC protocols adapt poorly

How to manage priorities of these traffic on the mesh

Multi-hop wireless has many interactions that reduce end-to-end throughput

HDTV, voice, tele-medicine requires some QoS guarantees

Wireless links are very diverse and have different properties

Some of the MAC protocols adapt poorly

How to manage priorities of these traffic on the mesh

Thanks!Thanks!

Suman BanerjeeSuman Banerjee

Wisconsin Wireless and NetworkinG Systems (WiNGS) Laboratory