International Business Machines Corporation

3com Corporation

Ericsson Gmbh

Anthony D Walker

Bradley S Trubey

Jay L Smith

David E Bartolini

James L Moran

Carl John Lindeborg

John Griesing

Liz Lindell

Edward Carroll

Robert B Hobgood

Vernon Roberts Norman

Lee Anton Sendelbach

Joseph Kinman Lee

Warren D Bailey

Kenneth J Christensen

Henry Michael Garrett

John S Petty

Kenneth T Wilson

Gregory Francis Paussa

Steven Eric Polge

Robert D Verne

Scott Tippens

Gregory A Mirek

David W Lowther

Dale R Chamberlain

Michele M Ferris

Erik L Dixon

A communication network implements a timing system that closely approximates network response times so that information may be transmitted between two data processing systems within the network in a timely and efficient manner. During operation of the communication network, a sending data processing system sends query data to a receiving data processing system. A response timer within the sending data processing system is initialized to track the query operation. If the receiving data processing system provides a response to the sending data processing system before the response timer expires, the timing implemented for data communications is proper for the communication network. However, if the receiving data processing system fails to provide a response within a time specified by the response timer, the transmitting data processing system resends a query frame. Subsequently, the sending data processing system in the communication network gradually increases a response time until the time measured by the response timer does not expire before a response is received by the sending data processing system.

Communication network having adjustable response timeouts and method therefore

A system and method for updating software for a remote unit over a network is disclosed herein. The system and method includes the remote unit, an authentication server and an update server. The remote unit may have a flasher host for communicating over the network and for transmitting commands to the remote unit. The system and method allows for the verification of a request message from the remote unit, and a response from the authentication server. The response message to the remote unit from the authentication server will contain an decryption key to decrypt the update file that will be sent by the update server. Such an authentication process prevents rogue programs from being sent to the remote unit thereby decreasing the potential for cellular fraud.

System for secure controlled electronic memory updates via networks

A token ring network performs address to port mapping by taking advantage of the abilities of the port switched modules and the neighbor notification process, in order to perform address to port mapping on each individual module. Ring monitors are switched from an upstream side of a port to a downstream side of a port when the neighbor notification process enters the port domain. The processor on the module records all the addresses received on the downstream side of the port, when the neighbor notification process is in the domain of that port. If it appears that the neighbor notification process is in the domain of two adjacent ports, the present invention only records addresses from the most downstream of the two adjacent ports, since such a situation is an indication that the upstream ports do not conform to MAC protocol. If a non-protocol station is connected to the last port in a module, the module will collect addresses from that port until the neighbor notification process enters the most upstream port of the module. At that point, addresses are no longer recorded in the most downstream port, and each set of addresses for each port are checked to determine if the last entry in each port has the ARI bits set to one and the source address is similar to the address of the most upstream neighbor of the module. If the addresses are the same, all addresses recorded in that port are ignored, since that port contains a non-protocol station.

Method and apparatus for address to port mapping in a token ring network

Beacon recovery is performed separately on each module. After a module recognizes that a beacon condition has occurred, each module checks to determine if the defect or fault is on its module. If the defect is on the respective module, the module disconnects itself from the remaining modules in the network and transmits a beacon frame onto an upstream end of the group of stations on that module. Each port on the module is then tested to determine if the error lies in the corresponding station. This testing is based on the presence or absence of the beacon frame.

Method and apparatus for correcting a defect in a token ring network

A process for testing a wrapped segment of a dual token ring transmits idle signals on the segment and monitors the received signals. If either an Active Monitor, Standby Monitor or Beacon frame is received the process loops. If a Ring Purge frame is received the process exits successfully and the segment is unwrapped. If a timer expires prior to the above, transmission shifts to a Claim Token frame. The process loops if a Beacon frame is received or if one of two timers expires. The process exits and the segment is unwrapped if a Ring purge frame is received or if n Claim Token frames are received having the hub source address.

Method for merging wrapped media segments onto a working network

A data communications system including a network and a number of data communication stations attached to the network wherein each of the stations includes a processor, a memory, a bus, and a communications adaptor for operatively connecting the processor and memory to the network, the communications adaptor including a means for monitoring network activity on a real time basis and enabling or disabling data compression when network activity exceeds a predetermined threshold.

System for selectively compressing data transferred in network in

In a serial network which includes a hub having a plurality of ports each for attaching one or more stations a mechanism for correlating a list of stations developed in a poll cycle to the ports and for detecting and resolving ambiguities when the number of stations does not equal the number of active ports. The mechanism uses a combination of input and output buffers under control of the programmed hub processor for developing a list of stations connected to the hub. When the number of stations does not equal the number of active hub ports an upstream buffer is configured to transmit Duplicate Address MAC frames to a single port and the contents of a downstream buffer are used to resolve the ambiguity either on a single transmission or multiple single port transmissions.

Port address resolution device

A network interface card for attaching computers, work stations or the like to a Local Area Network (LAN) includes a device which indicates an address compare if selected bits in a first part of an address, in the address field of a received frame, matches bits stored in the network interface card and at least one bit of a code word stored at a particular address of an index RAM is set to a predetermined state. The particular address in the index RAM is identified by a second part of the address in the received frame. The range of address which can be recognized is further extended by a contents addressable memory (CAM) coupled to the device. The CAM makes a parallel compare between an input address and its contents and outputs a match signal if a match is found. A programmable control register is used to activate or deactivate the CAM or the device.

Multiple group address recognition

A serial network fault isolation device for use in a network hub has receive and transmit buffers connected to the network. An isolation switch which allows the receive buffer to receive network signals while the transmit buffer sends signals such as media access control (MAC) frames supplied by the hub processor. A decoder connected to the receive buffer recognizes received (MAC) frames and interrupts the hub processor which reads the MAC frame. An idle character generator also under control of the hub processor is used to synchronize the circuit when the hub processor inserts the fault isolation device in the network.

Serial network fault detection, isolation and restorative device

A system (such as a multiprotocol LAN adapter) for use in a workstation or other processing machine automatically determines the type of network to which the workstation is connected and for automatically determines the type of physical medium to which the workstation is attached. The system has a plurality of different physical ports for supporting various available physical media over which network data may be transmitted. For example, the system may have a port for connecting to shielded twisted pair (STP) wiring, a port for connecting to unshielded twisted pair (UTP) wiring, a port for connecting to coaxial cable, and a port for supporting the Attachment Unit Interface (AUI). Connected to each of these physical ports are various network interface devices for supporting the various available networking protocols, e.g., token ring, Ethernet, etc. Logic circuitry and control software are connected to the network interface devices. In order to determine the valid network connections to the individual ports, a short interrogation frame is successively transmitted by each of the network interface devices to each of the ports. Depending upon the status of each transmission, the system determines what type of network (if any) is connected to and by which type of physical medium. Based upon these two determinations, the workstation can be automatically configured without user intervention.

System and method for determining network connectivity

Stations on a faulty token ring which includes a control adapter are removed one at a time starting with the most down stream station from the control adapter or of a station up stream from the last station is known to be good all of the stations down stream from that station are removed and the one at a time removal starts with the known good station. The control adapter transmits special beacon frames during the station removal process and when the removal of a station results in receipt of the special beacon frame at the control adapter, the control program identifies a fault domain which includes the station whose removal caused the special beacon to be received at the control adapter and the station immediately up stream from that station. The stations in the fault domain are selectively subjected tests and removed from the ring when a failure is detected.

Dual ring fault isolation

A multiport access and reconfiguration unit for use in a dual token ring network is provided with three adapters and, depending on error conditions, can assume one of a plurality of recovery states in which a reconfigured single network is formed and at least one state in which an isolated single ring is formed in addition to the reconfigured ring.

Dual ring reconfiguration switching unit

A plurality of access ports in a serial communication network are bracketed by a pair of adapters each of which is connected to a programmed processor. The adapters have unique identities and take part in a polling sequence with any active connected devices each of which have unique network identities. The processor maintains active port status information and correlates the identities of the devices received between the identities of the adapters in a polling sequence to the active port status information which indicates the specific port to which each active device is attached.

Serial network topology and recognfiguration generator

A multiport access and reconfiguration unit for use in a dual token ring network is provided with three adapters which in the presence of an internal fault establishes an isolated token ring which includes one of the adapters and the associated ports, to test and bypass the fault and operate the reconfigured ring with the other two adapters.

Growing community of inventors

Durham, NC, United States of America

Anthony D Walker