Research And Implementation Of The Embedded IPv6 Stack Based On 8-Bit MCU

With the rapid development of computer technology, IPv4 address space is almost exhausted, which prevents large numbers of inexpensive and small embedded devices from accessing Internet. As the core protocol in Next Generation Networks, IPv6 can preferably solve the problems which the current IPv4 faces, and can adapt the requirements of future network infrastructure on quantity and quality. Nowadays, there is no mature embedded IPv6 stack for 8-bit MCU at home and abroad. Therefore, IPv6 is introduced, which can implement the function of accessing Internet by low-end embedded devices and have high scientific research value and economic benefits.This paper presents the design and implementation of an embedded IPv6 stack based on 8-bit MCU, including IPv6, ICMPv6, Neighbor Discovery, TCP protocols and network interfaces. The layered architecture is adopted by the protocol stack. In order to simplify the protocol implementation, the complicated IPv6 is pruned aiming at the trait that MCU's source is limited. Meanwhile the stack adopts method of modularization, and the architecture is clear, easy to extend. Otherwise, in the aspects of data structure and memory management etc, many methods are considered aiming at 8-bit MCU's characteristics. The configuration of the hardware and the driver for Ethernet controller are also explained in detail. Finally, based on the implementation of IPv6 stack, giving comparison with IPv4 stack ''LwIP'', performance analysis by combinations of test results and protocol mechanism is accomplished.The hardware platform of the stack is based on C8051F020 MCU and Ethernet controller CP2200. The stack can run steadily, it has small code size and engrosses little memory when running, which adapts to low-end embedded devices. It can be repoted and extended easily. The performance analysis results have important instructional significations for the research personnel who implement IPv6 on low-end embedded devices.