## 4 System Design and Goals
### Modification to Message Intervals and New Message Variables  
In wireless routing protocols, message intervals and message variables play a critical role in determining how efficiently and reliably the protocol operates. These elements are crucial for maintaining up-to-date routing information, detecting changes in the network topology, and ensuring timely transmission between nodes in a network. This paper proposed new message variables that regulate the control message broadcast interval in the proposed routing protocol. These message intervals and new message variables are crucial for the proper functioning and performance optimization of routing protocols in wireless networks. They help to ensure that the network can adapt to dynamic changes, maintain accurate routing information, and provide efficient data forwarding. The new variables under this parameter are as follows:  
* DB_SELF_INTERVAL (DSI);
* DB_NIEGHORS_RCVR_INTERVAL (DNRI);
* DB_NIEGHORS_BOTH_INTERVAL (DNRI);
* DB_ROUTES_INTERVAL (DRI);
* EMERGENCY_HELLO (EH);
* LISTEN_MIN_INTERVAL (LMI);
* LISTEN_INTERVAL (LI). \(DB\_SELF\_INTERVAL\) (\(DSI\)) is the state where D2D communication nodes are handling their own database or internal data structures, and is related to maintaining local information about itself, such as its interfaces, neighbors, or routing tables. The default time in seconds proposed for nodes to update their Local Set is 2 s. Therefore, \(DSI=2\). \(DB\_NIEGHORS\_RCVR\) _INTERVAL (\(DNRI\))_ is the state where a node has received information about its neighbors, typically through a HELLO or TC messages. In this state, the node might be updating its internal database or data structures with the newly received neighbor information. The DNRI interval is crucial for maintaining up-to-date and accurate routing information, particularly in dynamic networks where neighbor relationships can change frequently. The default time in seconds proposed for nodes to update their Link and Neighbor Sets is 5 s. Therefore, \(DNRI=5\). \(DB\_NIEGHORS\_BOTH\) _INTERVAL (\(DNRI\)):_DB_NIEGHORS\_BOTH_ is a state or condition where a node maintains information about neighbors that have a bidirectional relationship. In networking, bidirectional (or symmetric) links are those where two nodes can both send and receive messages to/from each other successfully. This is important for certain routing protocols that require bidirectional communication between neighbors to establish reliable routes. The DB_NEIGHORS\_BOTH INTERVAL refers to the interval at which a node in an update or network verifies the status of its symmetric neighbor relationships. This interval is used to ensure that the information about neighbors is up-to-date and reflects the current state of the D2D communication network. The default time in seconds proposed for nodes to update their Link and Neighbor Sets is 5 s. Therefore, \(DNRI=5\). \(DB\_ROUTES\) _INTERVAL (DRI)_: Nodes across the network use advertised links extracted from TC messages to populate and update their link and Neighbor sets. The default time in seconds proposed for nodes to update their Link and Neighbor Sets is 10 s per group of symmetric one-hop nodes. _EMERGENCY_HELLO (EH)_: This variable determines which node or group of nodes has priority HELLO broadcast. Priority HELLO broadcast occurs after the expiration of the DSI. Nodes that broadcasted HELLO must set EH to 0; nodes that did not emit HELLO but emitted HI or heard the HI message without emitting a HELLO message must set EH to 1. Other variables that are important for the efficient performance of our proposed routing protocol are LISTEN_MIN_INTERVAL (LMI) and LISTEN_INTERVAL (LI). LMI represents the minimum time before the transmission of the HELLO message by a D2D communication node with a default LMI of 2 s, while LI represents the maximum time before the transmission of a HELLO message by a D2D communication node. Both LMI and LI can be exited early if the node in this state hears a HELLO message. The defaultLI = 3.