1. Castles A Strategy Game Exploring Mobile Collaborative Adaptive Software Matthew Chalmers, Malcolm Hall, Marek Bell University of Glasgow, UK

2. Castles And Some Other Seamful Games Matthew Chalmers, Malcolm Hall, Marek Bell University of Glasgow, UK

3. Background Seamful games as a testbed for ubicomp research ‘Seamfully’ revealing system structure and use Combining histories from multiple people, programs & devices Using wireless networks to share or disseminate information Bandwidth and memory: constraints and possibilities Wired and long-range ‘infrastructure’ wireless networks: slow/costly? Short-range wireless networks, e.g. 802.11, UWB: fast and free? Substantial memory in mobile devices (backed up by servers online?)

4. Treasure (a.k.a. Bill) Two teams of players, Blue and Green Each player has PDA+802.11+GPS Designed for disconnection Server drops coins on each PDA’s map Coin locations often outside network Only receive this info when in network Get close, pickup coins, get back into network, upload, get points Pickpocket: steals another player’s coins Only works when in network area Shield: protection from pickpockets Real-time maps of sampled coverage Based on history of movement

5. Bandwidth and Memory 802.11: hot spots set in cold expanses Cost and ownership are significant constraints too Many 802.11 apps assume constant access to one network …but perform poorly on mobile devices that are really mobile Peer-to-peer mobile ad hoc networks Rely less on central servers, active Internet connection, particular access points, having a specific static IP address… Issues of transience and security High short-range bandwidth, taking advantage of local storage New possibilities for interaction and gaming

6. Monopoly Wi-fi hotspots in the city are used as ‘properties’ Players’ PDAs detect and identify wi-fi access points First player to find a property can ‘buy’ it Other players owe rent if they pass by Rent paid in face-to-face meetings between players Information spreads peer-to-peer, between players Small ‘ad hoc’ networks between players’ PDAs Epidemic algorithms for spreading state P2P Rent due, players’ locations, new properties, bids to buy, offers to sell…

7. Yoshii Feeding (Illegal Version) Some play is indoors/online Home wi-fi used like a (glowing) hotspot for street players Also maps, stats and similar web paraphernalia Most play is out in the street with PDAs Looking for wi-fi hotspots and other players Can auto-connect to net through AP? A Yoshi lives there (and a Yoshi likes fruit) Bring Yoshi its desired fruit to get a game point Can’t connect through the AP? It’s presented as a plantation, to seed and pick fruit from Players can connect to each other directly: MANETs Swapping/stealing fruit, and info on plantations & Yoshis

8. Yoshii Feeding (Legal Version) Some play is indoors/online Web site shows game score tables Most play is out in the street with PDAs Looking for wi-fi hotspots and other players Open AP? A Yoshi lives there (and a Yoshi likes fruit) Bring Yoshi its desired fruit to get a game point Closed AP? It’s presented as a plantation, to seed and pick fruit from Players can connect to each other directly: MANETs Swapping/stealing fruit, and info on plantations & Yoshis Stripped-down version available at www.yoshigame.comwww.yoshigame.com

9. Castles: First Prototype

10. Domino Castles’ subsystem for handling assemblies of software components P2P ad hoc recommendations of software modules Dynamic sharing, dependency resolution and integration Recommendation based on patterns of use, and on classes and dependencies But users express utility or contextual relevance in and through their use Designers specify module’s class and class dependencies Social and technical means for security and privacy Transfer done as part of face-to-face game play Also: certification of modules? Sandbox? Showing logs of use?

11. The Current State of Affairs Legal Yoshi user trial just finished Stripped-down downloadable version just made available Pilot runs of Castles recently done Same base set of 54 components: buildings, adapters and units And also two other buildings, two other adapters, one extra unit Recommendations helped players who had poor setups Full trials of Castles beginning in October Interface and comms improvements, larger component set Video and system logs sync’d for playback in Replayer tool Issues of uniformity of system structure: the cost of winning battles? Building Bluetooth version of Domino infrastructure Links with U. Nottingham, UCL, U. Bristol and Blast Theory

12. Conclusion Games as a testbed for ubicomp, ubicomp as a testbed for games Exploiting fast comms and storage of mobile devices Seamful exposure of system (infra)structure Past use as a resource for adaptation of system structure and ongoing use Castles: system adaptation as part of a multiplayer game More coarse-grained and accessible than modding code How will players handle dynamics, develop strategies and adapt game play?

13. matthew@dcs.gla.ac.uk www.dcs.gla.ac.uk/~matthew www.equator.ac.uk