Implementation of gigabit ethernet controller with fault tolerance and prevention mechanism

Due to its high bandwidth, good maintainability and flexibility, Gigabit Ethernet is confoundedly suitable for high-performance server applications. As an interface between network and host, Ethernet controller has been continually evolving to meet the ever increasing communication demands being placed on it by enterprise applications. For the Ethernet, network links and physical devices, such as controller and switch, are likely to be out of order, which may result in system paralysis, service interruption and even intolerable consequence, especially when there are critical programs running on servers. In this scenario, Ethernet controller needs to not only achieve data reception and transmission, but also provide supports to the latest associate technology and standards. The objective of this paper therefore to design and implement an enhanced Gigabit Ethernet controller, called LCE5718, that provides fault tolerant transmission and prevention mechanism based on IEEE 802.3ad link aggregation and Network Controller Sideband Interface (NC-SI) respectively. Equipped with dual-port, LCE5718 is able to support link aggregation technology that can prevent connectivity loss even if one of the channels is out-of-order. In addition, we achieve a fault prevention mechanism in LCE5718 based on NC-SI. When prevention mechanism is adopted, potential device faults can be prevented by instantly reporting device's abnormal status to administrator and the corrective actions could be taken immediately. We also implemented LCE5718 in FPGA and performed experiments to evaluate its performance. The experiment results indicate that LCE5718 not only can guarantee fault tolerance transmission, but also can provide an effective prevention of network paralysis caused by device fault.