Icfcc conference real
- 1. How bad TCP suffers from packet losses and delays over wireless ad hoc networkMay Zin Oo, Mazliza OthmanFaculty of Computer Science & Information Technology University of Malaya Malaysia3rd to 5th April
- 9. The wireless devices can communicate each other without using central access points in peer-to-peer fashion , but these are within range of each other.
- 11. The determination of which nodes forward data is made dynamically based on the network connectivity.Applying TCP to Ad Hoc Environment TCP (Transmission Control Protocol)
- 12. To provide flow control, congestion control & avoidance, in-order and reliable end-to-end delivery of data packet in the wired networks.
- 14. TCP has to face many problems such as packet losses due to congestion and node mobility, wireless high bit errors, and so on.
- 15. Because of these problems, the following TCP versions were intended for wireless environment:
- 16. Tahoe, Reno, NewReno, Vegas and WestwoodTCP Versions for Ad Hoc Network TCP Tahoe introduced slow start and congestion avoidance.
- 18. Use at the beginning of a transfer or after timeout
- 30. Simulation Methodology Network Simulator (NS-2) was used to study the three variants of TCP over three ad hoc routing protocols.123012340123401234Simulation Methodology (Continued…)Static ad hoc environment ( 5 nodes & 15 nodes )…56714Fig 1: Source node 0 connects to destination node 4 in static ad hoc networkFig 3: Source node 0 connects to destination node 14 in static ad hoc network2712 Mobile ad hoc environment ( 5 nodes & 15 nodes )…………267012814Fig 2: Source node 0 connects to destination node 4 in mobile ad hoc networkFig 4:Source node 0 connects to destination node 14 in mobile ad hoc network
- 31. Simulation ResultsWe simulate each variant of TCP over each routing protocol in static ad hoc network and mobile ad hoc network environments and measure how the node mobility affects TCP and routing protocols in 5-node and 15-node chain topologies.
- 35. Throughput of received packets at the destination node.Packet loss rate (%) measurement of DSDVFigure 1Figure 2
- 38. Comparison of data transfer rate in static environmentVegas is the fastest data transfer rate under various conditions.Figure 7Figure 8
- 40. Measurement of the throughput in mobile ad hoc networkAll TCP variants over DSDV routing protocol can still receive packets although nodes move out of each other’s transmission range.
- 42. Although DSR routing protocol suffer from most packet losses, the number of received packets at destination nodes are the most.ConclusionIn the overview of performance comparison , according to the packet loss rate (%) , NewReno over AODV routing in mobile environment but in less nodes,
- 44. Westwood over DSR routing in both environment are the best and least packet loss rate.