FRAME Project page

FRAME : Failure Resistent Agents in Mobile Environment

Description

Implement channels for mobile devices... communication by messages focused on interactions combine conception and deployment ... with some static nodes as a backbone.
For mobile nodes ... Connection fault are just normal Different connection status depending on "who the device is connected to"
Storing and conciliating data on static nodes with a DHT ... Using static nodes as reliable backbone network Storage for data by offline nodes Ordering properties for messages

Project Team

• Olivier Marin - Assistant Professor (LIP6 - SRC/Regal - France)
• Frederic Peschanski - Assistant Professor (LIP6 - DESIR/SMA - France)
• Corentin Mehat - PhD Student (LIP6 - SRC/Regal - France)

Documents

• EuroSys'08 Doctoral Workshop
• proposal : Proposal accepted at the Doctoral Workshop
• poster : Poster presented at the Doctoral Workshop poster session
This poster presents the overall placement and architecture of this project.
We have a bi-partitioned physical architecture :

• on one hand we got the mobile devices that can move randomly in the space and thus can either be connected or disconnected.
• on the other hand are the static nodes that serves as access points and backbone network. They are physically static but do not necessarily are reliable

The Goal :
We aim at providing a framework to specify communications between mobile devices. Hence we need to deal with un-connected states and transitions (connections, deconnection, reconnection).

The backbone network :
distributed storage and reconciliation to the mobile devices.

Connection status
Mobiles nodes interacts between themselves and with the backbone network. This leads to different connection states for the mobile devices. This is always considered as a local point of view.

• disconnected : the mobile device is not connected to any other mobile device nor any access point of the backbone network.
• locally connected : the mobile device is only connected to other mobile devices that are present in it's neighborhood
• backbone connected : the mobile device is connected to the backbone network by at least one access point, and no other mobile device is present in the neighborhood (hence there is no connection possible).
• backbone and locally connected : the mobile device is connected to the backbone network by at least one access point, but is also connected to other mobile devices.

The hypthesis we put is that eventually, every mobile node will be at least backbone connected in order to propagate it's data to the static nodes. This will authorize an ordering of the messages emitted and a sercurely storage of the nodes using a DHT-like structure.

The Data emitted & the channel model :
We consider the data as "raw data" and the content of what is transmitted is not considered. There is no theorical limit to the size of each block but a limit will be set depending on the implementation.
Every message is emitted on one given channel. Our channels are considered to be "N-M", meaning that at every single point in time we can have N different writers and M different readers. This is much like a publish-subscribe mechanism unless that it's not synchronous as most p/s system do.

The DHT to ensure persistance
A DHT-like system (like Pastry for example) will be used to store the data sent throught the channels in order to leave access to the data emitted by a disconnected peer to another peer.

Unsolved questions :


• Make an Atomic Broadcast while maintaining the channel registration data and the replication of stored data over the peers.

Pages

• (here)
• dev and wiki (restricted access)
• Interaction spaces project