Rebroadcasting Schemes

Rebroadcasting schemes are strategies used in wireless networks, particularly in Mobile Ad hoc Networks (MANETs), to efficiently forward messages from a source node to other nodes in the network. Rebroadcasting schemes minimize the number of transmissions in a broadcast message. They attempt to deliver a broadcast packet to each and every intended node in the network. The primary purpose of rebroadcasting schemes is to retransmit data packets when they are not successfully received by their intended destination or when the sender's reach does not cover the entire network. Rebroadcasting is essential in ad hoc networks to ensure that data packets reach their intended destinations, especially in scenarios where nodes may move, network topology changes, or link failures occur.

Common Attributes of Rebroadcasting Schemes

Selective Rebroadcasting

Most rebroadcasting schemes aim to be selective in deciding which nodes should rebroadcast a packet. This selectivity helps reduce unnecessary rebroadcasts and control network traffic.

Loop Prevention

Preventing broadcast storms and packet looping is a primary attribute. Many schemes incorporate mechanisms to ensure that packets are not endlessly rebroadcasted and to avoid creating loops in the network.

Collision Avoidance

Rebroadcasting schemes typically include mechanisms to minimize packet collisions, which can occur when multiple nodes rebroadcast simultaneously and interfere with each other's transmissions.

Neighbor Knowledge

Some schemes use information about neighbors to determine whether to rebroadcast. Nodes prioritize rebroadcasting to well-connected neighbors or those more likely to reach the intended destinations.

Geographical Information

Geographic-based schemes use location information to guide rebroadcast decisions. Nodes may rebroadcast only to nodes within a certain distance or geographic region to maximize message coverage.

Energy Efficiency

Energy-aware schemes take nodes' energy levels into account when deciding to rebroadcast. They aim to avoid rebroadcasts that could drain energy resources, thereby prolonging network lifetime.

Message Tracking

Some schemes track messages that have already been rebroadcasted by a node. This prevents nodes from rebroadcasting the same message multiple times and reduces redundancy.

Message Sequence Numbers

Assigning sequence numbers to messages helps prevent duplicate rebroadcasts. Nodes use sequence numbers to recognize whether they've already rebroadcasted a particular message.