curtis oelmann

CURTIS OELMANN

Autonomous Mobile Mesh Networks and their Design

Changes

Ad hoc wireless networks Set of mobile nodes that are:

Self-organizingSelf-healingSurvivableInstantaneously available

all without having infrastructure

Multi-hop mesh networks Has two or more hops to any one node. These networks should also have

multiple paths to get to a particular node. The data being transmitted will “hop” to

each node until the data reaches its particular destination.

Must be able to update the current layout of the mesh network incase a node leaves the area.

Mobile Mesh Networks Autonomous Multi-hop Highly dynamic Human-centric Broadband mesh networks

Categorization of mesh networks

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History of the wireless network

Public Safety Services Work on the 4.94 - 4.990GHz band

Car accidents and first responders Surveillance-youtube.com

Disaster relief Hurricane Katrina

If there had been a mesh network, nodes from inside New Orleans would have been able to pinpoint where people were.

With surveillance cameras mounted on telephone poles, the data would have been able to go from hop to hop transmitting data back to the first responders and police.

The people we seen looting from stores would have been prosecuted because the police would have had video

Defense/Military operations Easily torn down and set up

On the move support

Voice over ip

Consumer/Home Networking New Blu-ray Dvd players

Surround sound

Wireless routers are limited, with multi-hop devices, the range is much greater.

Transportation Applications I-pass

Mobile mesh VS Fixed mesh networks

Example of a autonomous wireless network

Physical Radio Channels Commercial-off-the –shelf (COTS) Work on the 802.11 standard Allows access to many types of devices

todayPDALaptopsCell phonesOther home appliances

Medium of Mesh networks Can work with access points connected to

the internet or company intranet. Task Group S

OSI layer 2 mesh ○ Called ‘Extended Service Set (ESS) Mesh

Networking’ Autonomous systems can stand alone, so

the discovery process is needed to find other nodes in the area that are also supporting this type of access.

Routing and Multicasting We need :

A way to discover if a new node has entered the group

A way to update the group is a node goes down or leaves the group

A way to minimize the number of hops data takes to reach the destination.

A way to maximize the bandwidth being usedA way to minimize power consumption by the

nodes

Choosing a Route On-demand

The routes are established when a packet is sent. When the receiver gets a packet, they look at the route it took, and get the layout topology of other nodes in the group

ProactiveThe nodes are continuously updating the

topology by sending small packets○ High overhead

Route Reestablishment Class exercise

Security Wireless eavesdropping

Wal-Mart Example DOS

‘Node a’ sending countless packets to ‘node b’ could block access to other node, ‘node c’ from being able to use ‘node b’ to get to ‘node d’

IP Addressing Needs have a large set of address

space IPv6IPv4 only give 4 billion addresses

○ It is feasible for two computers to have the same address.

IPv6 would give 2128 or about 3.4×1038

Helps With DAD (duplicate address detection systems)

Roaming Node should be able to:

Roam from one network to anotherConnections should be seamlessShould not lose connections to data that

may be criticalAcquire new IP addresses instantaneously

whether another autonomous mesh or a fixed mesh

Applications Real time video Voice over Multi-hop mesh Instant Multimedia messaging Resource tracking Affinity group