Abstract: A communication network switch comprises a control module having a control processor and a plurality of communication modules connected to the control module via a control interface. Each communication module comprises a detector for detecting errors associated with communication signals such as read and write access requests received from the control module and a device for reporting the detected errors to the control module. Detected errors are stored in registers in the control module and are read by error detection software running on the control processor. The software module reports the errors and determines whether the cause of the errors can be corrected, and if so takes corrective action. Error detection software can also be simultaneously run on a redundant control module, and detected errors independently reported and passed to the active control module.

Abstract: Communication protocol interface systems and methods are disclosed. A predetermined type of content of communication traffic of a first communication protocol, illustratively control information, is translated into a corresponding type of content of communication traffic of a second communication protocol. The translated communication traffic is transferred to a first component of a communication device, which is configured to transfer the corresponding type of content to a second component of the communication device. The second component is configured for processing the predetermined type of content. In some embodiments, other types of content are translated for direct processing by the first component. Mechanisms are thereby provided, for example, for transferring control information through a packet processor to a host processor, while allowing data to be processed normally by the packet processor.

Abstract: A heterogeneous point-to-point links involves different technologies at it two ends, e.g., Ethernet at one end and ATM or Frame Relay at the other end. If two IP systems are connected via a heterogeneous point-to-point link, each may be using different address learning techniques. It is up to the Provider Edge devices to make these different techniques inter-work. A novel provider edge device and procedures that the edge device it to perform for forwarding packets properly are described. According to the invention, the provider edge device uses a broadcast address to forward the packet in one direction toward a customer edge device. In another direction, the provider edge device responds to an ARP request from the customer edge device with its own MAC address so that it can receive a packet from the customer edge device.