Notes
Outline
A PROXY SERVER INFRASTRUCTURE
FOR ADAPTIVE MOBILE APPLICATIONS
Jianwen Wang and Thomas Kunz
Systems and Computer Engineering
Carleton University
http://kunz-pc.sce.carleton.ca/
tkunz@sce.carleton.ca
Motivation: The “Mobile Warrior”
Related Work
Typically, related work focuses on bandwidth variation
Other resources are also constrained (memory, power, CPU capabilities) and may vary over time
Majority of solutions: introduce proxy between client (application executing on mobile device) and server, proxy compresses and filters data stream
sometimes, degree of compression depends on available bandwidth
user mobility often not addressed/supported
Some other solutions:
view mobile purely as User Interface (WWW browsers, Teleporting, ....)
statically partition client application between mobile and proxy
dynamically partition client application between mobile and proxy
partition directed by application (Rover, MaROS, ....)
partition transparent to application (using mobile code toolkits)
Generic Architecture
(presented at AI ‘99)
Sample Application: MPEG Player
Runtime System
Collecting System Parameters
Experimental Setup
Results
Conclusions and Future Work
Goal: facilitate design, implementation and deployment of new and innovative PCS services (resource-intense, multi-medial)
emphasis on transparently overcoming resource limitations and variances in available resources (power, bandwidth, memory, CPU speed)
resource variations exist during executions as well as between executions (cellphone vs. PDAs vs. laptop)
explore mobile code as unifying framework to investigate resource tradeoffs
Open issues:
collecting link bandwidth
costs of migration/handoff
use of hysteresis similar to location mgmt in cellular networks
load balancing between client and proxy (under way)
include WinCE or Palms (necessitates new mobile code toolkit)
comparison to “traditional” approaches, active networks
scalability to provincial or country-wide deployment: simulation