Apple Inc.

Alan B Oppenheimer

Gursharan S Sidhu

Ronald Ray Hochsprung

Sean J Findley

Lawrence A Kenyon

Jonathan M Zweig

Kerry E Lynn

Michael W Ritter

Jeffery L Mullins

James E Mathis

A method and apparatus for assigning a unique network address to a first node within a network which is arbitrarily connected. The first node may include a shared network resource, such as a networked printer device, or a modem, in addition to a stand-alone computer system. The network may include a network which is wireless, wherein various nodes comprise radio transceiver circuitry, including radio frequency modems. A first provisional network address for use in assigning the unique network address is determined by the first node. The first node broadcasts probes containing the provisional network address until a first probe response to one of the probes is received or a first interval of time elapses. If the first probe response to one of the probes is received, then the first node determines a second provisional network address and repeats selection of the address and broadcasting, until no probe response is received in the first interval of time. Using the first provisional network address, the first node broadcasts forward probes in the network until a second probe response to one of the forward probes is received by the first node or a second period of time has transpired. If a second probe response to one of the forward probes is received by the first node, then the first node determines a third provisional network address and repeats the steps of selecting, broadcasting probes and forward probes until no the response is received in the second interval of time. The final provisional network address may be used as the unique network address for the first node.

Dynamic address assignment in an arbitrarily connected network

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. 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. If an entity in the first set of nodes has the alias, then the entity transmits a reply signal, which includes its network address, to the transmitting node.

Method and apparatus for determining whether an alias is available to

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. A first entity having the alias then transmits a fourth signal, which includes its network address, to the second entity in response to the third signal.

Network device location using multicast

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. If all node ID's for an address are checked, then another network number is selected from the range and node ID's are again selected to determine a unique address. Once a unique address is ascertained, this is stored back into a parameter RAM area for a subsequent power up initialization and is used for the unique identification of the first entity.

Local area network device startup process

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. Re-transmission is attempted using a linear back off method which is adjusted based on previous cable traffic history.

Local area network with self assigned address method

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. Re-transmission is attempted using a linear back off method which is adjusted based on previous cable traffic history.

Growing community of inventors

Cupertino, CA, United States of America

Alan B Oppenheimer