Abstract: A remote access server provides a remote user with access to a local computer network. The server receives a user identification string from its communication port, the string having been entered by the remote user at a remote computer which is coupled to the communication port. The string identifies the remote user. The server uses the string to access a database and determine an internet protocol (IP) address associated with the string. The remote computer needs the IP address to communicate on the local computer network. The database includes a user identification string for each remote user and an IP address for each string. The remote access server sends the IP address to the remote computer via the communication port. The server then allows the remote computer to access the local computer network and to communicate on the local computer network using the IP address.

Abstract: A multiport source routing token ring bridge is provided which permits a single local area network bridge to interconnect to multiple remote bridges without limitations on the number of rings and bridges interspersed between a data packet's source and its intended destination. The bridge receives a packet and then scans the packet for ring-in information which matches the ring to which the bridge is attached. If this match is not successful, then the packet is not passed to the software and the address recognize and frame copy bits at the end of the packet are not set. If the match is successful, then the bridge number and next ring-in (or ring-out) segment information from the packet are used as addresses to a static RAM array. The array is preprogrammed with all valid bridge number and ring-out combinations which may be accessed by the multiport source routing bridge.

Abstract: An apparatus and method for learning and filtering destination and source addresses in a local area network (LAN) system is provided to facilitate the transfer of information packets from one local area network to another. The apparatus provides a link between two (or more) remotely located LANS through the use of a LAN bridge. The apparatus has a LAN controller interface, a microprocessor, a state machine and one or more content addressable memories which function to monitor an information packet received from the LAN. One such apparatus is connected to each of the LANs to be interfaced and each of these apparatus to each other in order to communicate messages between the LANs. Upon detection of an information packet, the apparatus examines both the source and destination addresses of the packet. The source address is compared to a dynamically generated table of source addresses and then compared to the incoming destination address.