Issue link: https://read.uberflip.com/i/1499940
5177 Brandi n Court, Frem ont, CA94538 | Tel : +1 51 0 -4 9 2 -4044 | Fax : +1 510 -4 9 2 -4001 | www.l o ra -al l i anc e.org IPv6 LoRaWAN Adaptation Layer FAQ IPv6 LoRaWAN Adaptation Layer FAQs 1. What is SCHC? SCHC stands for Static Context Header Compression and fragmentation. It defines compression and fragmentation mechanisms to transport datagrams over LPWAN technologies, and can be used to efficiently transport IPv6/UDP datagrams over LoRaWAN. 2. What is the architecture overview of SCHC? End Device App +--------------+ +----+ +----+ |App1 App2 App3| |App1| |App2| | | | | | | | UDP | |UDP | |UDP | | IPv6 | |IPv6| |IPv6| | | | | | | |SCHC C/D & F/R| | | | | | | | | | | | LoRaWAN | | | | | +-------+------+ +----+ +----+ | +-------+ +-------+ +-----------+ +------------+ +~ |Gateway| == |LoRaWAN| == |Application|==|SCHC Gateway| .. Internet .. | | |network| |server | | F/R- C/D | +-------+ |server | | | +------------+ +-------+ +-----------+ The Compression/Decompression (C/D) and Fragmentation/Reassembly (F/R) happens between the application and LoRaWAN layers. 3. What can SCHC over LoRaWAN do? SCHC is used for two purposes: • Compression, when some parts of the LoRaWAN payload are known to be static, i.e., bits and bytes do not change over time. E.g., a device's IPv6 address. • Fragmentation, when the payload is expected to exceed the LoRaWAN MTU. SCHC provides isolation between the application and the LoRaWAN variable MTU, i.e., the SCHC layer will take care of fragmenting the application message, if required, in as many and as small fragments as needed by the current LoRaWAN data rate.