The 6LoWPAN adaptation layer defines compression, fragmentation and reassembly, and frame delivery mechanisms for IPv6 datagrams. As specified in RFC 4944, when an entire IPv6 datagram fits within a single IEEE Std 802.15.4 frame, then the datagram is transmitted unfragmented without adding a fragmentation header in the LoWPAN encapsulation. On the opposite hand, if the compressed IPv6 datagram is larger than the IEEE Std 802.15.4 MTU (i.e., 127 bytes), then fragmentation is required to split the large datagram into multiple link-layer fragments of up to 127 bytes. The length of each link fragment is specified in multiples of eight bytes. The first part of this talk will be dedicated to the whole process of 6LoWPAN Fragmentation and Reassembly operation. The second part of the talk will be dedicated to 6LoWPAN Frame Delivery modes, the mesh under and the route over (or Per-Hop Fragmentation and Reassembly mode). Both approaches are widely employed in the Smart Grid networks around the world. The first mode takes place at the 6LoWPAN adaptation layer, where the nodes require the knowledge of the routes at Layer 2 based on MAC, whereas the second mode does it at Layer 3 based on IP. Finally, in the third and last part of the talk, an alternate approach called 6LoWPAN Fragment Forwarding (6LFF), i.e., RFC 8930, will be presented, whereby an intermediate node forwards a fragment without reassembling the complete IPv6 datagram first.
This session will be presented by Georgios Z. Papadopoulos who has received the prestigious French national ANR JCJC 2017 grant for young researchers. He has been involved in the organization and program committee of many international events, such as IEEE ISCC’20, IEEE DIPI’19, AdHoc-Now’18, IEEE CSCN’18, GIIS’18, IEEE ISCC’17. Moreover, he has been serving as Associate Editor for Wireless Networks journal and Internet Technology Letters since 2018. He is author of more than 60 peer-reviewed publications in the area of computer communications, networks and cybersecurity. He actively participates at the IETF standards organization with multiple drafts in the ROLL and RAW Working Groups. His research interests include Industrial IoT, 6TiSCH, 6lo, LoRa & LPWAN, Wireless Battery Management System, Smart Grid, Cybersecurity and Moving Target Defense. Dr. Papadopoulos has received the Best Ph.D. Thesis Award granted by the University of Strasbourg and he was a recipient of two Best Paper Awards (IFIP Med-Hoc-Net’14 and IEEE SENSORS’14).