6LoWPAN header compresses with end-to-end hybrid route-over using cross-layer and adaptive backoff exponent

• Main Author: Awwad, Samer Adnan Ali Bani
• Format: Thesis
• Language: English
• Published: 2016
• Online Access: http://psasir.upm.edu.my/id/eprint/70195/1/FK%202017%20113%20-%20IR.pdf; http://psasir.upm.edu.my/id/eprint/70195/

In the world of Internet of Things (IoT) and wireless embedded internet, the IPv6 over Low-Power Wireless Personal Area Network (6LoWPAN) was specifically introduced to enable IPv6 global internet connectivity for Low-Power Wireless Personal Area Network (LOWPAN). However, this requires the LOWPAN embedded devices to run IPv6 protocol. On the other hand, enabling IPv6 protocol for embedded devices is not directly applicable due to limited IEEE 802.15.4 frame size, huge headers sizes and routing challenges. In 6LoWPAN, the headers such as TCP, UDP, IPv6 and IEEE 802.15.4 have relatively huge sizes. This depletes the frame payload to approximately 33 bytes. Some techniques are designed to compress the packet's headers and provide more space for actual data payload. These compression techniques individually compress each fragment in the packet, and hence similar redundant headers are carried by these fragments. In this thesis, a compression scheme called Second and Subsequent Fragments Headers Compression (S&SFHC) for 6LoWPAN network is presented. The S&SFHC scheme exploits the correlation between the first and the subsequent fragments' headers, hence the redundant headers are not carried again by the second and subsequent fragments. The S&SFHC scheme can work either as a standalone or be integrated with other compression techniques. The S&SFHC standalone mode achieves up to 40% higher packet delivery ratio, 12% lower average delay and 35% lower average energy consumption compared to LOWPAN Internet Protocol Header Compression (LOWPAN_IPHC). Furthermore, in integrated mode, where S&SFHC and LOWPAN_IPHC are integrated together, it achieves up to 30% higher packet delivery ratio, 20% lower average delay and 24% lower average energy consumption compared to the LOWPAN_IPHC when packet size grows up to 600 bytes. The thesis also presents a hybrid Route-Over routing protocol with End-to-End fragmentation and reassembly using Adaptive Backoff Exponents (ROE2E-ABE). In this protocol, end-to-end fragmentation and reassembly is adopted to reduce the average end-to-end delay, while an adaptive backoff exponents mechanism is adopted to maintain high packet delivery ratio. This protocol can avoid both the high packet loss rate of enhanced route-over which happens due to collision, and the high average end-to-end delay of conventional route-over which happens due to hop-by-hop fragmentation and reassembly. Hence, this protocol enjoys both advantages of high packet deliver ratio of conventional route-over routing and low average end-to-end delay of enhanced route-over routing. The ROE2E-ABE achieves up to 23% higher packet delivery ratio over that of route-over with hop-by-hop fragmentation and reassembly when the packet size is increased to 600 bytes. In addition, it achieves up to 80% lower average end-to-end delay compared to route-over with end-to-end fragmentation and reassembly while achieving higher throughput and lower average energy consumption. Both S&SFHC and ROE2E-ABE have been integrated. This results in up to 10% higher packet delivery ratio, 17% lower average end-to-end delay, 10% higher total throughput and 13% lower average energy consumption than ROE2E-ABE without S&SFHC integration. Finally, the thesis presents a mathematical performance analysis for conventional route-over, enhanced route-over and ROE2E-ABE routing protocols in terms of packet delivery ratio, average end-to-end delay and average energy consumption.