In my last post I spoke in depth on a potential topic for a dissertation. Given that much else isn’t really happening at University besides dissertation work, I thought this may be a good time to talk vaguely about what I’m actually doing for my dissertation.
My dissertation is on a topic called Opportunistic Networks. Now, Opportunistic Networks are very different from normal networks such as the internet. With the internet, you’re only part of the network if your device (such as phone or laptop) is actually connected to the network (try to resist making a smart-alec comment for a moment). Obviously, in the rare cases when your device is not connected to the internet (touch wood), you are said to be disconnected from the internet or network. Still with me? Good. With Opportunistic Networks, by default, all devices that are part of the network are disconnected (Say what?). Connections are only made when necessary and as soon as they are no longer needed, those connections are broken (hence the name Opportunistic Networks, as connections are made when there is an opportunity). Still with me? Didn’t think so. Who’s the smart-alec now?
This will make more sense with an example. So Opportunistic Networks typically use technology to communicate that doesn’t require a cell tower but that only requires the devices trying to communicate (without some additional central control). This could be Bluetooth or Infra-red. They definitely wouldn’t use your typical cell-network or Wifi. In this day and age where everything seems to offer Wifi and you always seem to be within range of a mobile network, it can be hard to see why an Opportunistic Network could be useful. You may even argue that they’re completely redundant. However, I would argue, that you haven’t been to Wales (I mean RURAL Wales. Cardiff University would like me to add that there is cell network coverage and WiFi throughout the University…).
Imagine this: if you’re amongst a team of people exploring a rainforest, how are you going to communicate with the rest of your team spread over the forest? Now you could build a big meaty cell tower in the middle of the rainforest, but the authorities might have issues with that given that it would require a large amount of deforestation and the eradication of a number of endangered species. However, if you can get around that, by all means, build the cell tower. Now the second option (which is the most economical option, might I add) is for all the researchers to carry Vuvuzelas on their person and communicate in Morse code. The third option is to scatter some cheap Bluetooth nodes from a plane (do you get to fly in a plane in the first two options? I don’t think so!) and then communicate with each other via Bluetooth. Now, hold up, how is an explorer going to communicate with another who is miles away? Bluetooth’s range is less than 100 metres! Well the message can hop between Bluetooth nodes (that you scattered from a PLANE) and other explorer’s devices until it reaches the required destination. You may think this would imply a huge delay for messages to get to their destination but you’d be wrong (so wrong). As routing algorithms have been designed (and are still an active research area) that can intelligently choose which node to pass the message onto next so that it can reach its destination within the shortest time possible (or smallest number of hops). What’s more, the explorers/researchers could drop these cheap Bluetooth nodes as they walk from their lab into the forest, thereby allowing them to communicate with the guys back in the lab when need be. However, that might make the plane redundant so don’t do that. This third option is what’s used in real life (and will continue to be provided the scientists don’t get hit by too many cuts; otherwise we may have to resort to the second option).
For my dissertation, I’m making an Android application that will communicate with every device it encounters (as you go about your daily routine) and exchange songs being played on Spotify. So if you were listening to music on Spotify and you went past people who also had Spotify, their device would share a song with your device that your device would then add to your playlist. This would typically be a song that the other person was either listening to or listens to a lot (so not just some random song). Of course your device would also share the song that you’re currently listening too. Now some of you may have spotted a potential problem, that being, if you walk past a school, on your way to a first date, would your playlist be suddenly filled with One Direction and Spice Girl songs (not to mention a dozen remixes of ‘Let it go’). Well, uhuh, it wouldn’t if they’re already in your playlist. However, the application will only add songs shared with it that it thinks match your taste in music. So you needn’t worry about turning up to your first date with the words ‘If you wanna be my lover, you gotta get with my friends’ blasting out of your leaky headphones.
So while the internet is spreading even to remote areas now, there will still always be a need for Opportunistic networks as some places (such as rainforests and mountain ranges) are unlikely to ever get internet connections. Besides that, they provide a massive, ahem, opportunity to create social applications that change the user experience/recommendations based on the people he/she encounters.