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One of the major challenges in mobile ad-hoc networks is designing an efficient routing protocol that can cope with high mobility network as mentioned in Ram, Murphy, and Manoj (2004). To achieve this, a number of routing protocols have been proposed such as Perkins, Belding-Royer, and Das (2003)Johnson, Hu, and Maltz (2007), Clausen and Jacquet (2003), Broch, Maltz, Johnson, Hu, and Jetcheva (1998), Das, Perkins, and Royer (2000), Weiss, Hiertz, and Xu (2005). These protocols can be classified into on demand/reactive routing protocols and table driven/proactive routing protocols. The proactive routing protocols are considered not scalable compared to the reactive routing approach because of the excessive routing overhead associated with the periodic dissemination of routing tables among all the mobile nodes in the network. In addition, the power and bandwidth consumption in the proactive approach are increased due to the exchange of routing tables among the mobile nodes after each change in the node’s position. On the other hand, the reactive routing protocols are considered more scalable than the proactive protocols, since they can significantly decrease the routing overhead and power consumption. This is because the reactive routing approach does not need to keep searching and maintaining these routes when there is no data traffic to send as stated in Royer and Toh (1999). However, the biggest challenge in reactive single path protocols such as DSR protocol is the route re-establishment after the link to the next hop fails because there is lack of the route maintenance mechanism during the data transmission which leads to cause more link failure in MANET. The link failure is common in mobile ad-hoc network scenarios due to the node mobility. There are many studies that have been done in the previous work to improve the performance of DSR protocol regarding the route maintenance such as Aissani, Senouci, Demigna, and Mellouk (2007), Alejandro, Samuel, and Benjamin (2004), Sengul and Kravets (2006), Susmit, Soumen, Sahnawaj, Barun, and Bhunia (2008), Shiva, Rajeev, Brijesh, and Kumar (2011). These protocols are based on the single path routing approach which means that the routing protocol relies on unipath route for each data session. However, due to the node movement out of the transmission range and the dynamic characteristics of the radio channel, the active link fails between two pairs of node as stated in Biradar, Koushik, Sarkar, and Puttamadappa (2010). Nevertheless, if there is no route available in the route cache of the intermediate node due to high mobility network, the data packets will be dropped and the route error message will be sent back to the source node. After the source node receives this message, it initiates a new discovery process to discover a new route. However, discovering a new route in mobile ad-hoc network requires considerable resources such as network bandwidth and power as mentioned by Trung, Benjapolakul, and Duc (2007). Thus, DSR protocol requires adaptive route maintenance to handle the link failures effectively without degrading the overall network performance and avoids sending an unnecessary route error packet upon link failure. In fact, these problems can be eliminated by discovering multiple paths between a source and a destination in the single route discovery process where one route can be used as primary route (shortest route), and the rest as backup route (secondary route). Recently, several different multipath routing protocols based on DSR protocol have been proposed in the literature regarding the route maintenance mechanism such as Koh, Oh, and Woo (2003), Vahedi, Mohseni, and Darehshoorzadeh (2007), Kun-Ming, Chang, and Shi-Feng (2011), Yang and Huang (2008), Kajikawa, Fukuhara, Bouk, and Sasase (2009). These protocols establish multiple routes either link or node disjoint routes in single route discovery, and they try to maintain the alternative routes (backup routes) after the primary route (shortest route) fails to send the data packets to the destination. The selection of alternative routes is based on the route cache of each intermediate node. The current route cache of DSR protocol does not have any update mechanism to update the routing information of each intermediate node. In case the primary route fails to send the data packets to the destination, the alternative route is selected from the route cache. However, in the high mobility network, the alternative route may be invalid at that time which leads to drop the data packets and another route discovery is initiated from the source node. Therefore, RM-DSR protocol proposed to improve the performance of DSR single path protocol. The developed protocol utilizes multiple established node disjoint routes to send different data packets to the destination and utilizing the routing table to store the learned routes during the route discovery process. There are three main challenges for designing a multipath routing protocol in mobile ad-hoc networks. First, is how to discover a multiple node disjoint routes with minimum routing overhead during the route discovery process. Second, is how to select the route after the link to the next hop is broken Third, is how to distribute the data packets into different multiple routes. In this respect, RM-DSR protocol constructs five elements based on the challenges in multipath routing protocols. The first and second elements are the control messages and the data structures which are discussed in Husieen, Hassan, and Ghazali (2012).