Abstract: A method and apparatus for determining whether an alias (or entity name) is available for use in a communication system. A transmitting node or entity transmits a first signal including the alias over the communication system. The alias includes a zone name. If the transmitting node receives a reply signal to the first signal, then the alias is not available for use. Otherwise the alias is available for use. The transmitting node transmits the first signal to a first router connected to a first local network of the communication system. The first router forwards a second signal including the entity name from the first signal to other routers in the network until a second router connected to nodes having the zone name in the entity name is located. Each second router translates the second signal into a third signal which includes the alias, and using a first zone multicast address, multicasts the third signal to a first set of nodes.

Abstract: A method and apparatus for determining the location of an entity using an alias (or entity name) in a communication system. A second node or entity transmits a first signal to a first router connected to a first local network of the communication system including the alias, wherein the alias includes a zone name. The first router forwards a second signal including the entity name from the first signal to other routers in the network until a second router connected to nodes having the zone name in the entity name is located. Each second router translates the second signal into a third signal which includes the alias, and using a first zone multicast address, multicasts the third signal to a first set of nodes. Each node of the first set of nodes determines whether the zone name contained within the alias is equal to a zone identifier for each node of the first set of nodes. Each node having the zone name determines whether the alias contained within the third signal is equal to alias information for the node.

Abstract: Method used by a first entity, typically a computer system, on a communication system for assigning itself a unique address known as a network address, which comprises a network number and a node identification number. The entity determines a unique network address for itself within a local subset of entities known as a local area network (LAN). A signal is then transmitted to determine whether a router is connected to the LAN, and if so, to determine if the network number of the address is within a range allowed by the router. If the network number is not within a range allowed by the router, then another network number is selected from a range of numbers provided by the router and another node ID are selected. It is determined whether this value is being used by any other entities in the LAN, and if so, node ID's are selected until an unused network address is ascertained.

Abstract: A local area network is disclosed including apparatus and methods for transferring data between a plurality of data processing resources ("agents") coupled to a cable. In the preferred embodiment, a plurality of agents are coupled to a common cable for data transmission and reception. An agent newly coupled to the cable dynamically assigns itself a unique address on the cable to which other agents may send data. Once an agent has been assigned a final address, it may then transmit to, and receive data from, other agents on the cable. An agent desiring to send data to a receiving agent follows a three step handshake, wherein the sending agent transmits an "RTS" signal and within a predetermined time must receive a "CTS" signal from the receiving agent. The sending agent then transmits a data frame within a predetermined time after the CTS signal is received. The failure to detect a return CTS signal within the predetermined time denotes a collision condition.

Abstract: A local area network is disclosed including apparatus and methods for transferring data between a plurality of data processing resources ("agents") coupled to a cable. In the preferred embodiment, a plurality of agents are coupled to a common cable for data transmission and reception. An agent newly coupled to the cable dynamically assigns itself a unique address on the cable to which other agents may send data. Once an agent has been assigned a final address, it may then transmit to, and receive data from, other agents on the cable. An agent desiring to send data to a receiving agent follows a three step handshake, wherein the sending agent transmits an "RTS" signal and within a predetermined time must receive a "CTS"signal from the receiving agent. The sending agent then transmits a data frame within a predetermined time after the CTS signal is received. The failure to detect a return CTS signal within the predetermined time denotes a collision condition.