Adapting switch port and work station communication adapters to data frame types with disparate formats and data rates

摘要

This invention relates to "clear pipe" communication networks meaning the nodes and links handle a variety of data frame types depending on their communication protocols such as Token Ring, Ethernet, FDDI or ATM. More particularly, this invention relates to node/link interface adapters at nodes which include switching nodes and end nodes. The adapters identify data frame type and adapt the node/link adapter operative elements to handle the various types of data frames as they travel through the network. The invention identifies the frame type at the source, flags the frame type to the nodes by use of unique SDEL (start delimiter) symbols or codes, uses the SDEL codes as received with the frame at each node to find the destination address in the frame and to adjust the transmission rate for the frame. The transmission rate is adjusted by inserting null non-data symbols in the frame to effectively slow the data rate to the data rate capacity of the protocol.