## 2 Selected Routing Protocols  
The main goal of routing in WMNs is to establish the most efficient path for the transmission of data packets between source and destination nodes within the network. Routing protocols in WMNs may be classified into three categories, proactive, reactive, and hybrid, according to their packet forwarding approaches (Figure 2) [16]. Proactive routing protocols, or table-driven systems, create routes to all accessible destination nodes, irrespective of their necessity for data transfer. They constantly estimate the pathways to all nodes that can be reached and provide consistent and up-to-date routing information. Thus, the primary advantage of proactive protocols lies in their ability to enable nodes to swiftly acquire routing information and establish communication pathways with minimal delay [17, 18]. Reactive routing protocols, also known as on-demand methods, establish routes only when required. When the source node needs a route to a destination node, the route discovery process is activated. This procedure persists until a route is discovered or until all possible paths have been assessed and deemed unavailable. In mobile networks, active routes may be disrupted due to node mobility. However, in WMNs, node mobility is relatively limited, enhancing the scalability of reactive routing protocols [19, 20]. Hybrid routing protocols combine the strengths of both proactive and reactive approaches, addressing their respective limitations to determine optimal routes while minimizing management overhead. These protocols deploy different routing strategies in various segments of the WMN architecture. Reactive protocols are employed within the ad hoc network regions, whereas proactive protocols are utilized in the wireless backbone, facilitating efficient and effective routing processes [21, 22]. In this article, we consider three proactive routing protocols--OLSR, BATMAN, and Babel--due to their prevalent use in the recent literature [13, 14, 15, 16, 17, 18] and their broad application across diverse communication scenarios [23, 24, 25, 26, 27]. These protocols have been extensively studied [17, 18, 23, 24, 25] for their effectiveness and adaptability in various network environments, making them ideal candidates for evaluating performance in a WMN. Figure 2: Sorting of WMN routing protocols. OLSR is an optimized version of the standard channel state routing algorithm, and it has two versions. Version 1 (OLSRv1) was presented by the French National Institute for Research in Computer Science and Management (INRIA). Version 2 (OLSRv2) is an updated version of OLSR1, and it retains the same mechanism, but with some improvements [28, 29, 30]. OLSRv1 is a proactive routing protocol, which continuously updates and maintains a network topology map to enable efficient data transfer between network nodes. In this protocol, each node within the network broadcasts its current link state information to all other nodes. The OLSRv1 algorithm uses two types of control massages, such as HELLO and TOPOLOGY CONTROL (TC). Periodically, TC messages are transmitted only by MPR hosts. Multipoint relays (MPRs) are an essential aspect of the OLSRv1 protocol to minimize broadcast transmission. Each node chooses a set of MPRs from its neighbors that has a one hop bidirectional link to all other nodes that are two hops away. This set may vary depending on the time specified by the selecting nodes in their HELLO messages. When a node transmits a message, all its neighboring nodes receive it. Only MPRs that receive the message for the first time will propagate it further. As a result, the amount of flooding overhead can be decreased. The OLSRRv1 offers an advantage over other proactive protocols by broadcasting its link state information instead of routing tables. This allows messages to be delivered in any order due to the use of sequence numbers. OLSRv1 is particularly well suited for large and dense networks [31, 32, 33].