Wireless Mobile & Multimedia Networking - DSR

A situation where multiple nodes in a network simultaneously send route reply messages, leading to network congestion and inefficiency. This can occur when multiple nodes are responding to the same route request.

To prevent a node from sending a route reply if it receives another route reply with a shorter path to the destination.

Introducing random delays before sending route replies to avoid simultaneous transmissions and reduce the likelihood of a route reply storm.

When network bandwidth is used inefficiently, potentially due to factors like collisions, route reply storms, or excessive traffic.

The size of a network, which can impact efficiency depending on the number of nodes and the amount of traffic.

The process of finding a path from a source node to a destination node in a network.

A message sent by a node when it needs to find a route to another node.

The nodes that receive an RREQ packet and forward it towards the destination node.

The first node that sends an RREQ packet, initiating route discovery.

The final node that the RREQ packet is supposed to reach.

The sequence of nodes that form the path from the source to the destination node.

The number assigned to each RREQ packet to help track them.

When an RREQ packet travels through intermediate nodes, the path it takes is recorded in the packet.

Reactive routing protocols are a type of on-demand routing. They only activate path-finding and information exchange when a node needs to communicate with a destination. This means there are no scheduled updates or constant information sharing.

DSR is a reactive routing protocol that aims to minimize bandwidth usage by avoiding constant routing updates. It uses source-based routing where the source node initiates the route discovery and knows the entire path to the destination.

Route discovery is the process of finding a path between a source node and a destination node in DSR. This process is initiated by the source and involves sending out route request packets, which are then forwarded by intermediate nodes until the destination is reached.

Once a path is discovered in DSR, the source node stores the complete route in a route cache. This cache allows the source to efficiently reuse the found path for future communication with the same destination.

DSR implements a route maintenance mechanism to handle changes in the network like node failures or link disruptions. If a path breaks, the source node is notified and can initiate a new route discovery to find an alternative path.

In DSR, the source node sends a route request packet to the destination, requesting a route back to the source. Intermediate nodes along the path forward the packet toward the destination, eventually reaching the destination node.

When a destination node receives a route request from the source, it sends back a route reply packet containing the entire path back to the source. This reply packet is then forwarded by intermediate nodes back to the source, providing the source with the complete path.

DSR maintains routes by continuously monitoring the network for changes. If a node or link fails, the source node can detect this and initiate a new route discovery. This ensures a reliable communication path even under dynamic network conditions.