Lime Team Adam Bazinet Hau San Si Tou

What is LIME?  LIME stands for Linda In a Mobile Environment Linda : a shared memory computing model developed in the mid 1980’s  A Java-based middleware system for developing applications in mobile ad hoc networks  Provides a coordination layer to deal with both physical and logical mobility

Physical vs. Logical Mobility  Physical mobility concerns the movement of mobile hosts Hosts roam across the physical space and modify the topology of the network  Logical mobility concerns the movement of mobile agents Processes are able to migrate from one host to another while preserving their code and state

The LIME Environment  Coordination is achieved through a tuple space globally shared among components tuple space is a multiset of tuples that can be accessed concurrently by several processes  Components do not need to co-exist in time for them to communicate  Components can reside anywhere in the distributed system  Components can access the tuple space by inserting, reading, or withdrawing tuples containing information

LIME Distribution  Composed of 4 packages: lime contains the core functions of Lime lime.util contains the Launcher class, used for starting the runtime lime.util.console contains a graphical console for interacting with a LimeTupleSpace lime.mobileagent.mucode provides Lime-enabled mobile agents

Important Concepts  Lime Agents The only active entities in LIME The only components that carry a “concrete” tuple space with them. Programmatically represented by Java threads  Transiently Shared Tuple Spaces An extension of the standard Linda tuple space

More Concepts  Tuple Location The tuples in the tuple spaces are physically stored across the multiple hosts in the system Each tuple is an ordered sequence of typed data  Engagement/Disengagement of Hosts Engagement : the process of a host coming into range Disengagement : the departure of a host Both processes are atomic  Reacting to Changes in Context Reaction : defined by a method to be executed when a tuple matching a specific pattern is found in the tuple space

Tuple Space  Interface Tuple Space (ITS) Permanently and exclusively attached to the unit itself Contains tuples the mobile unit is willing to make availabe to other units, and that are concretely co-located with the unit itself The only content accessible to the unit when it is alone  Host-Level Tuple Space The transiently shared ITSs belonging to multiple agents co-located on a host

Tuple Space  Federated Tuple Space Connection of Host-Level Tuple Spaces Formed when components are within range i.e. mobile agents are on the same host or communication is available between mobile hosts which contain agents

Tuple Space Figure

“Applications”- a. k. a. Games  Roaming Jigsaw

RedRover

Project Objectives  Understand the software packages that are available  Work to implement a “lightweight” version of Lime that works with the m2m protocol- Anhinga Spaces  Develop and demonstrate some applications using our Lime bundle

The Source 