Challenges of MANETs

A Manet environment has to overcome certain issues of limitation and inefficiency. It includes:
  • ·         The wireless link characteristics are time-varying in nature: There are transmission impediments like fading, path loss, blockage and interference that adds to the susceptible behavior of  wireless channels. The reliability of wireless transmission is resisted by different factors.
  • ·         Limited range of wireless transmission – The limited radio band results in reduced data rates compared to the wireless networks. Hence optimal usage of bandwidth is necessary by keeping low overhead as possible.
  • ·         Packet losses due to errors in transmission – MANETs experience higher packet loss due to factors such as hidden terminals that results in collisions, wireless channel issues (high bit error rate (BER)), interference, and frequent breakage in paths caused by mobility of nodes, increased collisions due to the presence of hidden terminals and uni-directional links.
  • ·         Route changes due to mobility- The dynamic nature of network topology results in frequent path breaks.
  • ·         Frequent network partitions- The random movement of nodes often leads to partition of the network. This mostly affects the intermediate nodes.

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