There were people from 40 different countries there and I feel like I met someone from almost every one of them at some point. There were over 300 people at AINA this year, which apparently is down from the last couple of years (where they had 4-500) but it was still a great conference for me. I will post my slides from my presentation in this post in case anyone is interested, along with a link to the paper once it is available. I submitted another paper last night for a conference in Toronto and am working on two more papers, so hopefully I’ll be travelling soon. I am trying to aim for ICC in South Africa next year.

Here are a few pictures from the conference.

Abstract:
This paper addresses the problem of scheduling in Wireless Mesh Networks (WMNs). The paper first discusses existing scheduling algorithms and classifies them based on the technique they use and their implementation frameworks.Then detailed discussions of the proposed scheduling method are presented. Simulation experiments are conducted to compare the performance of fair scheduling with the method that does not use fair scheduling. The simulation results confirm that the proposed scheduling method has better performance with respect to the metrics used for performance evaluation.

J.B. Ernst, M.K. Denko, “Fair Scheduling with Multiple Gateways in Wireless Mesh Networks”, in Proc. of the 22nd IEEE Int. Conf. on Advanced Information Networking and Applications (AINA 2009), Bradford UK, 2009.

The paper itself is available through IEEE Xplore

Update Ubuntu:

Download the NS-2.33 and HWMP All-in-One Package here:

Updated with new link: *

Untar the file:

Configure and Install NS2

All ready to go. Enjoy.

I recently received a request for a guest contribution to the blog from Kelly Kilpatrick so I thought it would be a nice change to have some content from someone other than me. The article is a compilation of some good sites for the latest on wireless technology and news.

5 Blogs and Sites for All Things Wireless

Guest Contribution by Kelly Kilpatrick, October 14th, 2008

As wireless technology continues to advance, it is good to stay informed on the latest technologies, advances, and setbacks related to this convenient technology. However intricate or superficial, these blogs are out there to keep you informed (to one degree or another) regarding the latest and greatest developments in the world of wireless technology.

Engadget: For the latest news and analysis on a wide variety of wireless products and new innovations, engadget has you covered. Read about new hardware and WiMax-compatible products, as well as other developments that are in the works when you visit engadget.

Network World: The contributors at Network World are fully dedicated to finding out everything they can when it comes to the world of wireless. Read comparison reviews, find out the latest news in wireless technology, and learn more about what companies are doing to meet the ever-growing demand for better, faster wireless technologies.

Wireless Week: Wireless Week has several contributors dedicated to keeping the blog up-to-date and fresh. Browse through their substantial archives or look at their latest news and commentary regarding wireless technology. Keeping track of what’s going on in this constantly-evolving segment of computing technology just became a little bit easier with Wireless Week.

WiMax News: To stay current with the latest in this rapidly-growing wireless technology sector, visit WiMax news regularly. Troubleshooting, news, reviews, potential security threats, and much more can be found with a quick search. To stay ahead of the curve, take a look at WiMax News.

MuniWireless: A visit to this particular site will give you a wealth of knowledge related to wireless technology advances and setbacks around the world. Delivering information and articles prolifically, the folks at MuniWireless are certainly in touch with the latest happenings when it comes to wireless technology.

By-line:
This post was contributed by Kelly Kilpatrick, who writes on the subject of dial up internet. She invites your feedback at kellykilpatrick24 at gmail dot com

10. Wireless House

Everything in your house could be controlled by computers and wireless technology. The idea is not new but with wireless technology we have today it becomes even more possible.

One example of this is at IBM where they have a working kitchen that has counter-tops which can detect the type of food you place on them. This information can be then used to give a list of recipes for the various ingredients, suggest cooking times for an automatic microwave / stove or keep track of expiry dates for products. The items in the fridge can be listed without even opening it via an lcd screen on the front which can also double as a way to access the internet for recipes, to watch tv while cooking or ordering more food. Additionally, since it can be hooked up to the internet, the stock in the fridge can be queried from anywhere in the world (say at work) where you can have groceries delivered to your house ready for cooking later that night.

Similarly, other areas of the household could be controlled and manipulated using wireless technologies. Other examples are wireless security cameras, health care applications for patient monitoring, voice communications and more.

9. Wireless Agriculture

A key technology used in the above example of the wireless home is the wireless sensor. Research in this area of wireless networking is also quite popular. Wireless sensor networks have applications from monitoring volcanoes and forest fires to climate change in the oceans. Wireless sensors could also be used in other climate sensitive applications such as farming and agriculture.

For instance, I live near Niagara-on-Lake Ontario, Canada where wine making has become very popular recently. They make a particular type of wine called ice-wine which must be an exact temperature for a certain amount of time before it is harvested in order to qualify as ice-wine. Many times they have to call in their staff in the middle of the night in the winter (because that is when the ideal temperature is usually reached) but find out that the temperature is actually not quite cold enough yet. So all the workers are sent home and paid for three hours of work. If wireless sensors were used instead perhaps some money and time could be saved.

Additionally, many of the wineries have technology which circulates air around the fields to control the temperatures from become to extreme for the grapes to grow how they want. These devices could be controlled via wireless sensors spread across the vineyard as well. Similarly, in other areas of agriculture the same ideas could be applied.

8. Wireless Power Transmission

Communication over power lines is because electrical power is just a signal in a different band than the communications signals. So we should be able to do the same thing with wireless networks. People have proposed systems where we generate solar power in space (or on the moon) and use wireless signals to beam the power back down to earth (Since everyone is so concerned about clean energy these days I thought this one would be interesting to add).

7. Wireless People

Sensor network technology has been under development for years and has matured to a great degree in the last few. Imagine a system where every person in the world had a chip that could monitor their vital signs (heartbearts, body temperature etc) and then relay these to a central tracking facility such as a hospital or doctors office).

The units could be powered by the energy from blood pumping inside the body, the energy created from walking around, or possible some kind of solar interface. The data coule be relayed in a multi-hop network through each person to the central facitilities. Over time with enough data collected, computers should be able to predict when certain changes in the data are going to produce a heart attack or an blood clot and medical care could become more pre-emptive in areas where predicability is still a problem.

Additionally, farther along in the future similar technology could be used to communicate with others telepathically, to transmit thoughts, ideas etc to other people (its not that far-fetched, they have video game controllers which allow you to play games using brain signals via a headband strapped around your head)

6. Car PC – Home PC Music and Video Synchronization

It is becoming more and more popular to have a pc or a well equipped car stereo in a car these days. It would be nice it you could pull up to your driveway and all the music inside your house automatically synced itself into the car. Additionally, it would be even better if it could make use of a network anywhere (cellular, wifi or anything else it comes into contact with on the road) and sync up at anytime the music files in your house change.

5. Wireless Hospital

Using wireless technology in a hospital has many uses – patient and inventory tracking, cost savings on laying wires in older hospitals which need to send data around etc. The patient and inventory tracking can be done with existing technologies like RFID. This approach could help keep mentally ill patients in the hopsital or prevent mixups with newborns. Companies like Walmart already use this type of system to control inventory in their warehouses and for shipments (one scan can read every item in a trailer to save time and cut down on human error). The only concern in using this type of system in a hospital is that of privacy. No one wants unauthorized people to track them. Additionally, there are concerns that unauthorized people may also find it easier to locate medications and other items within the hospital for theft with such a system in place for inventory. However if this concerns can be overcome then this system could prove quite useful.

4. Remote Weather Stations, Buoys etc

The remote weather systems and buoys could make use of technology from Wireless Sensor networks to conserve energy and transmit data only when necessary to the collection stations. They could run on solar panels and the buoys could make use of the technology that allows energy to be captured from waves. If the deployment of either of these stations or buoys was dense enough the traffic could be relayed from the farther nodes inwards toward a central data collection station.

3. Wireless Traffic / Transit System

This system could be integrated into transit systems already in place. It could be implemented as a mesh network where routers are placed on buses, trains and other vehicles. The users in the vehicles could gain access to the network via the routers in the vehicles which would then relay the traffic through the network to gateways placed at strategic points in the city.

Also, the routers within the vehicles could be equipped with GPS or some other location technology that could be used to relay tracking information back to a website for transit users to plan their travels. Additionally, routers could be placed at various traffic signals and all of the signals in a city could be coordinated in a central control station.

Furthermore, sensors could be places around the road system to give an idea of traffic congestion patterns and other feedback about road conditions (or even in a farther futureistic scenario, cars could be scanned while driving to make sure they are not carrying bombs or other illicit substances).

2. Independent Private Wireless Community for File and Information Sharing

This could be used for people who like to trade files who are also worried about privacy concerns or people who are tired of public network traffic shaping (torrent traffic etc). This network would be independent from the internet however it could provide many of the same services to people. It could either be free or be on a subscription basis. (if subscription based it would likely require some kind of infrastructure investment) but if it were free, it could work in an ad-hoc arrangement where users connect together and agree to the terms of the community policies for sharing data. A problem that must be overcome however is some way to prevent the sharing of illicit or illegal content in this manner.

1. Community-Wide Wireless Mesh Network for Internet Access

This network could be deployed cheaply across an entire neighbourhood or even a city. The main benefit of the wireless mesh network is that not every router in the neighbourhood requires a wired internet connection. So there could be some kind of scheme where people who provide internet connections are able to make a small amount of money while people who normally cannot afford access could gain cheap or even free / publicly funded access to the network.

Additionally, if many people provide connections into the network, the capacity of the network increases, theoretically allowing access to more bandwidth than each individual connection could provide (ie One person may make use of bandwidth of 2 or 3 connections at once if the network is not busy congested).

The presentation gave a background on why load balancing and scheduling are important in WMNs. Additionally a survey on the current problems that I find interesting in the area was presented. In case you don’t want to get the presentation / you don’t have MS Office here are the main points from the presentation:

Why is Fair Scheduling Important in WMN:

• Starvation & Unequal Quality of Service (Qos) caused by “greedy” flows or proximity from Gateways which allow other traffic to be ignored or serviced unequally
• In commercial applications of WMNs customers pay equal amounts and expect equal service
• In many solutions that exist today, we cannot have Fairness and Throughput at the same time

Example of a Wireless Mesh Network : netdts.com

Why is Load Balancing Important in WMN:

• Multiple path redundancy is an important trait of WMN however instead of traffic being spread around the multiple links, often the same links become overused and congested while other links are barely used
• Load Balancing tries to solve this problem using at Mesh Routers, Gateways, and sometimes Links to attempt to spread the traffic around the network (although some papers claim that Load Balancing on the links isn’t effective)

Current Problems in Fair Scheduling and Load Balancing in WMN:

• Assumptions in some papers: single hop networks only, limited or no mobility (of the Mesh Routers), fixed topology (Mesh Routers cannot be added or removed and the topology is known at all times)
• Some papers assume that uplink and downlink scheduling can be treated the same when it may be beneficial to treat them independently
• Distributed Vs Centralized Scheduling & Load Balancing
• Future work on many papers cite experimentation with different metrics, optimal locations and number of gateways etc.
• Thorough investigation of load balancing at the gateways, links or mesh routers

If after all this you would still like the presentation, you can download it from the link below:

Download:

Fair Scheduling and Load Balancing in Wireless Mesh Networks by Jason Ernst. May 26th 2008.

An example Interconnection Graph Problem, Click to Enlarge

Since December of 2007 I have been working at implementing, testing and experimenting the algorithm as well as providing feedback and new ideas for improvements. The paper is almost ready to be submitted for publication this so hopefully I will be able to provide a link to it in the future.

In relation with my thesis, I am planning on making use of the CRIN algorithm to attempt to optimize wireless network protocols. There still needs to be some experimentation and research to determine if in fact the algorithm can be used in this way however I feel optimistic that this is the case.

There is also the potential that the source code for the CRIN implementation may be made open source and released for use by anyone. If this is the case it will be uploaded to this site in the future.

An example of a Wireless Mesh Network (WMN)

So why is this technology useful? Well current wireless networks usually depend on one access point as the gateway for all the wireless clients in the network. This approach creates a restrictive bottleneck at the access point. What if we could use multiple access points so that the clients are better spread out. Additionally, instead of having each access point being a gateway, what if only some of them were gateways. The rest can communicate with each other in a mesh structure that allows the data to flow to the gateways. This idea is not new, however there still are no satisfactory ways of doing this. There are many problems to consider which I plan to address in my thesis.

So you may still be wondering where in the real world all of this can be used. Well the obvious answer is in the military. But additionally, this technology could be used in warehouses and factories in place of their current wireless systems for product scanners. Many warehouses use systems that require a wired connection at each access point which in a warehouse can mean expensive wire being run all around needlessly. This new approach would require only a few access points to be hooked into a wired network and the rest of the traffic would flow towards these routers. Similarly, cellular phone companies could use the same technology to reduce the amount of cellular phone towers by configuring each phone as a mesh router. This would allow traffic to reach phones which are further from the existing towers by relaying through phones which are closer. The same technology could be integrated into vehicles allowing for deployment of computer networks along busy highways since access points could be put along the highway. This would allow the access to travel with the moving vehicles as they could route the network traffic towards vehicles which are closer to the access points. So there are plenty of ways this could be used in the real world. It is just a matter now of making it work effectively.

More to come eventually.