Distributed Dynamic Channel Allocation in Wireless Network

Channel Allocation Cellular network consists of cells. Mobile service station (MSS) is incharge of a cell. MSS makes all decision for channel allocation.

Message passing between MSS & its neighbors to avoid co-channel interference. Time stamped requests are sent by MSS to neighboring MSS for channel allocation. MSS Neighbour MSS Time stamped Request

Message Types MSS REQUEST RESPONSE Neighboring MSS CHANGE_MODE RELEASE ACQUISITION

Message Types REQUEST- requesting to acquire a channel. RESPONSE- responding to the request from receiving node. CHANGE_MODE- mode changed from local to borrowing or vice versa. RELEASE- sending node has released the channel. ACQUISITION- sending node has acquired a channel.

Implementation

Network Class Nodes: Arraylist of all nodes/MSS. Spectrum: Set of all channels

Node Class PR: set of primary channels. Use: set of currently used channels Iuse: Set of channel used by interfering node Mode: represents mode of the node i.e. Local or borrowing. Waiting: number of requests not received ACK. Pending: check if any pending request. Rounds: number of attempts to acquire channel in borrowing mode.

Public class Node extends Thread { Public Node () Super(); } Public void run () Node.request_channel(time); } } Public class MobileHost public static void main(String[] args) new Node(“MH1”).start(); new Node(“MH2”).start();

Concurrency 1. Multiple requests when node in local mode. MH1.Node1.request_channel || MH2.Node1.request_channel All requests are proceeded in parallel with no deadlock.

2. Multiple requests when node in borrowing mode. MH1.Node1.request_channel (r_Node2) || MH2.Node1.request_channel (r_Node2) Algorithm prioritize the request based on time stamps. i.e. Lower the timestamp higher the priority. Thus no need to apply external locks or synchronize methods.

Plan Implementing all the messages passed between nodes in java. Verify the behaviour in case of concurrency.

Thank You Questions ?