Cisco Technology, Inc.

James O'Toole

M Frans Kaashoek

Gang Lu

John H Jannotti

Barbara Liskov

Kirk Johnson

MArk Stuart Day

Stephen Jeffrey Morris

David M Bornstein

John J Jannotti

Anthony Lapolito

Content servers are directed to send messages to network nodes which are used to obtain IP addresses and to receive responses from the network nodes. The responses provide network service information. The content servers collect data based on the responses and feed the data to a routing server. Based on the data fed to the routing server, respective choices of content servers are selected and provided to the network nodes to respond to clients requesting content server addresses from the network nodes.

Content server selection for accessing content in a content distribution network

In one embodiment, a subnet mask is automatically determined by a first network node attached to a subnet in a packet communication network. The first network node issues plural communication packets from plural source addresses to at least one address known to be used in the subnet to evoke responses, and based on the presence or absence of responses from the network nodes at the known addresses, the first network node determines the subnet mask which represents the subnet.

Method and apparatus for determining a subnet mask based on presence or absence of responses to plural communication packets issued during a search iteration

Embodiments of the invention can resolve conflicts between candidate master network devices such as may be encountered in a failover condition. In a common type of failover protocol, two or more candidate master devices send messages to each other prior to a failover condition. A witness device (or process or service) also casts a vote to prevent a stalemate condition between the two candidate master devices that could lead to an error condition where multiple masters, or no masters, are elected.

Voting to establish a new network master device after a network failover

A method, system and apparatus are provided for securely connecting a peripheral device to a processing device in a wireless network. The peripheral device makes a request for access to the processing device, which generates a challenge message and prompts a user to respond. The peripheral device is allowed access to the processing device, based on the user's response. If the user's response validates the challenge message, access is allowed; otherwise it is disallowed.

Method and system for secure connection of peripheral device to processing device

In one embodiment, a first network node in a subnet retrieves a network configuration from a second network node located outside the subnet. The first network node communicates with at least one other network node to collect information from inter-node communication packets containing network address information other than an address assignment to the first network node. The first network node determines an available network address based on the network address information contained in the collected inter-node communication packets. The first network node is assigned the available network address and locates a network address for at least one subnet router. The network node accesses the second network node located outside the subnet, using the located network address for the at least one subnet router, for an available network configuration from a list of network configurations. The first network node is assigned the available network configuration.

Method and apparatus for retrieving network configuration from a remote network node

A method, system and apparatus are provided for dynamically pre-positioning content from servers located in a network, which may be a content distribution network. The content is pre-positioned on a proxy server, and the pre-positioning is triggered by at least one of the scheduling of an event and the presence of a user. Users commuting between different locations of a company can quickly and easily access the pre-positioned content. This content may be prioritized and pre-positioned, based on a user requiring a specific content at a particular time.

Method and system for dynamically pre-positioning content in a network based detecting or predicting user presence

A method, a system, and an apparatus are provided for wireless communication of a traffic signal over a network. A message comprising data related to the traffic signal is received. Thereafter, the forwardability of the message is detemined. If forwardable, the message is forwarded. The validity of the message is checked and if found to be valid, information in the data is communicated to a vehicle controller. The message is discarded, if it is found to be invalid.

Method and system for wireless signaling of vehicular traffic

The present invention may be used for determining a topology of a network in the presence of network address translation. From an active client behind a translating device, communications are initiated that effect the network address translation. The communications are monitored beyond the translating device to infer partitioning of servers into equivalence sets relative to the network topology induced by the network address translation. Active clients behind the translating device may include a respective actual sending address in a message sent to a server beyond the translating device. The server beyond the translating device distinguishes between communications affected by and not affected by network address translation, which may include comparing an apparent source address of a message against an actual address provided in the message by the active client behind the translation device. The external server may also distinguish between active and passive client messages. The server server may cause a message to a passive client to be redirected to an active client; the active client, in turn, communicates to the external server. The external server stores addresses of devices in translated address sets, which may be maintained in a database and managed in a database manager.

Method and apparatus for determining a network topology in the presence of network address translation

The present invention includes a method and apparatus for automatically assigning a network address to a network device in an electronic communications network carrying inter-device communication packets to and from electronic devices located at assigned network addresses. The network device, also referred to as an appliance, communicates with at least one other network device to collect information from inter-device communication packets, which contain network address assignment information. From the network address assignment information in the communication packets, the appliance determines an available network address. The appliance assumes the available network address. The appliance may access a remote network device to retrieve an available, permanent, network configuration, including IP address.

Method and apparatus for automatic network address assignment

The invention is directed to techniques for managing a network of nodes by automatically configuring the arrangement of nodes in the network. A network manager in a node selects a group of nodes and compares network metrics for each node in the group, such as a bottleneck bandwidth measurement from each node to a root node of the network. The network manager selects a target node using the network metrics. Optionally, the network manager can select a new group of nodes using the target node, compare network metrics for the new group, and optionally select a new target node. If the node is a newly connecting node to the network, the network manager can repeat this process of selecting new groups until establishing a relationship with a target node that is not a root node (e.g., with performance that is the same, or about the same, as the root node), because the goal is not to overload the root node with too many relationships. If the node is a node with an established relationship to the network that is trying to reconnect to a new target node, the network manager can repeat the process of selecting new groups until establishing a relationship with a new target node that provides improved performance than the previous target node, but is, preferably, not the root node.

Methods and apparatus for managing the arrangement of nodes in a network

The invention relates to a telephone conference system and an associated method. A conference phone includes a plurality of input audio signals and a spatial preference sensor adapted to identify a listening preference associated with at least one conference participant. The spatial preference sensor might indicate a head position of a conference participant, such that small movements of the participant's head control processing of a plurality of input signals resulting in a more audibly intelligible conference.

Head position based telephone conference system and associated method

The invention is directed to techniques for managing data distribution in a network. A source or root node distributes data (e.g., video data) throughout a network of nodes by distributing data from parent to child through a tree of nodes. The nodes distribute the data through the network concurrently in a real-time manner, but retain copies of the data in nonvolatile data storage on each node. Thus, the data remains accessible on each node so that the data is available after the real-time distribution of the data. After the real-time distribution of the data, a new node can attach to any of the nodes currently in the network as a child of that node, and then the new node can request a copy of the data from the data storage of that parent node.

Methods and apparatus for managing data distribution in a network

The invention is directed to techniques for maintaining a map of node relationships for a network of nodes (e.g., network of computers). In one example, the map of node relationships represents relationships overlaying and typically different from the network of physical connections among the nodes. Each child node periodically checks in with its parent nodes, and the parent nodes can thus determine when a child node has terminated a relationship with the parent or created a new relationship with a new parent. Changes in relationships propagate upward through the network of nodes so that each node maintains a map of the relationships among the descendants of that node. A root node receives the propagated change relationship information and maintains a map of the entire network and valid pathways through the network. The root node can use the map when responding to a request from a client to receive services from a node in the network and redirects the client to attach to a node in the network that has a valid path to the root node. The root node can then broadcast data (e.g. a stream of video data) throughout the network, which is received by all the clients attached to nodes in the network.

Methods and apparatus for maintaining a map of node relationships for a network

A network appliance is capable of remote booting and obtaining its configuration information from a source located far away. The network appliance can be shipped to a business location or office environment without requiring a local boot server in that location or environment and without requiring the presence of a person who is familiar with and highly skilled in configuring the appliance. The invention allows for booting and the obtaining of configuration information, and therefore allows for the functioning of the appliance, regardless of whether there is a local server in the local network environment, such as a DHCP server or a boot server, that has been set up and configured to provide to the appliance the booting and configuration information it requires.

Methods and apparatus for remote configuration of an appliance on a network

A network operator identifies an address of a network element used by a particular client to obtain IP addresses. The client sends a test message to a test URL which includes a unique host name unknown to the client or network element. The network element accesses an authoritative server, which records the IP address of the requesting network element and resolves the host name in the test URL to a test IP address. The server records an IP address of the client when the client subsequently sends a message directly to the test IP address. In an alternative embodiment, another network node generates a redirect command, which incorporates the client IP address in a test URL, to allow for single-message determination of the network element and client IP addresses by the authoritative server. In both embodiments, user unique test URLs may be generated to allow the network operator to assist many users.

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Somerville, MA, United States of America

James O'Toole