Internet gateway discovery approaches in multihop wireless networks

Technologies on mobile adhoc networks (MANETs) are the one that support self organizing and infrastructure less networks. The Internet Gateway (IGW) within the range of mobile nodes is used to establish the communication to the Internet for having access. The appropriate approach should be selected for gateway discovery and gateway selection for reliable connection between adhoc mobile nodes and the Internet. To connect to Internet some particular Internet gateway nodes are discovered by mobile nodes from MANET domain. Thus the important task is an Internet gateway discovery. There are many proposals suggested and implemented by different authors or researchers, but so far there is no unique and powerful solution has been discovered which can work in all the network functionality scenarios. In this work, we critically examine all the gateway discovery approaches and point out their merits and demerits with future directions in this emerging area.