Abstract: A method and apparatus are disclosed for estimating the location of a wireless terminal across multiple building floors. The illustrative embodiment determines the floor where the wireless terminal is presently located by using a majority logic-based heuristic. A plurality of signal monitors measure signals from the wireless terminal and provide those signal strength measurements to a location estimation server. Alternatively, the wireless terminal measures signals that are transmitted by a plurality of transmitting signal devices and provides those signal strength measurements to a location estimation server. The location estimation server determines the floor of the wireless terminal in accordance with the illustrative embodiment of the present invention.

Abstract: A method and apparatus are provided for authenticating the contents of a device requesting access to a first network, such as an enterprise network. If a device has connected to at least one other network then the content of the device is evaluated prior to obtaining access. The scope of the content evaluation may be based, for example, on properties of the other network or on one or more defined content authentication rules. If a device attempts to access a network, the content of the device is evaluated and the device may be restricted to accessing only one or more restoration services if the content fails to satisfy one or more predefined criteria, such as a content item that is out of date or a determination that the device connected to one or more external networks. The restoration service(s) can update a content item that is out of date, reinstall one or more programs or return configuration settings to default values.

Abstract: A technique is disclosed for detecting hidden wireless routers that constitute security threats in telecommunications networks that comprise a wireless network portion and a wireline network portion. In accordance with the illustrative embodiment of the invention, a test station is used in the wireless portion of a network to detect the presence of a hidden wireless router. Furthermore, in some embodiments, a test server is used in the wireline portion of the network in order to detect packets that are illegitimately routed from the wireless portion to the wireline portion of the network through the hidden wireless router.

Abstract: The present invention is a system and method for rapid network failure detection, identification and notification to internet users. It is particular applicable to VoIP applications where such real-time problem identification is particular valuable. It reduces failure detection time by coordinating the sending frequency of RTP and RTCP packets. These incoming packets are monitored and the failure to receive a predetermined number in a specified time window indicates that a network problem has occurred. This problem is then promptly communicated to users of the system.

Abstract: The present invention is a system and method to improve the reliability and performance of existing enterprise IP networks which have dual-homed (or multi-homed) network architectures. In one aspect of the invention packets related to a selected category of transmission (e.g., VoIP) are duplicated at an edge router and sent over both (multiple) service providers. After traversing the service provider networks, only the first-to-arrive packets are kept and the later-arriving copies are discarded. In so doing, the result is better protection against node failures, link failures, and packet errors, and also better QoS performance under normal (fault-free) operation.

Abstract: Updating of routers is achieved by insuring that the scheduling of router updates is such that a zone of turbulence that occurs where the updating takes place does not prevent reaching any router that may be in need of updating. For IP routers that have a task scheduling capability, this is achieved by estimating the time for communicating update information to all routers that need to be updated, adding that estimate to time of day, and transmitting the update specifications. In arrangements where routers do not have a task scheduling capability, updating is sequenced. One embodiment creates a set of traceroute trees that cover the nodes to be updated, and leaf nodes of the trees are taken up at random, placed in an ordered list and deleted from the trees. Another embodiment is more tree centric, in that once a starting node is identified (and its associated tree), all of its nodes are considered before progressing to another tree.

Abstract: A packet data filter which stores ordered rules and sequentially applies the rules to received data packets to determine the disposition of the data packet. The packet filter maintains a match count in memory which indicates the number of times each rule matched an incoming data packet. Periodically, at the initiation of a user, or based on operating parameters of the filter, the rules are automatically re-ordered based on the match count. As a result of the re-ordering, rules with higher match counts are moved earlier in the sequential evaluation order and rules with lower match counts are moved later in the sequential evaluation order. As such, rules which are more likely to match incoming data packets are evaluated earlier, thus avoiding the evaluation of later rules. In order to prevent a re-ordering which would change the overall security policy of the packet filter, pairs of rules are compared to determine if they conflict (i.e.

Abstract: A packet data filter which stores ordered rules and sequentially applies the rules to received data packets to determine the disposition of the data packet. The packet filter maintains a match count in memory which indicates the number of times each rule matched an incoming data packet. Periodically, at the initiation of a user, or based on operating parameters of the filter, the rules are automatically re-ordered based on the match count. As a result of the re-ordering, rules with higher match counts are moved earlier in the sequential evaluation order and rules with lower match counts are moved later in the sequential evaluation order. As such, rules which are more likely to match incoming data packets are evaluated earlier, thus avoiding the evaluation of later rules. In order to prevent a re-ordering which would change the overall security policy of the packet filter, pairs of rules are compared to determine if they conflict (i.e.

Abstract: A method and apparatus for determining locations for and placing k caches in a network for optimizing performance of a network parameter. The method includes the steps of selecting a placement parameter l that is greater than 0, assigning l caches to l arbitrary nodes in the network. selecting l caches to remove from the network, assigning l+1 caches to every possible location in the network, computing and recording network performance data on the network cost parameter for each location and for each selection of l caches, determining a location where the network performance data on the network cost parameter computed and recorded is optimized, assigning l+1 caches to the determined location, and repeating the above steps of selecting l caches, assigning l+1 caches, computing and recording network performance, determining a location, and assigning l+1 caches for k−1 iterations.

Abstract: In a communication arrangement including a multiplicity of intranets, objects available on the Internet are requested. A requested object in an intranet is attended by a proxy server therein, which attempts to locate a copy of the requested object in a proxy cache. The latter stores copies of objects previously obtained by web browsers in the intranet, and affords priority to copies of those objects from selected Internet sites. If the proxy server does not manage to locate a copy of the requested object or determines that a located copy is outdated, the proxy server seeks cooperation from other proxy servers to further search for the object. These cooperating proxy servers are dynamically identified by a manager processor in accordance with the invention. In addition, the manager processor prefetches selected objects from the Internet in anticipation of the object request. The manager processor also helps search the prefetched objects for the requested object.

Abstract: Online prediction techniques based on data compression principles are employed to make predictions in restricted memory environments. Predictors have data structures in the form of trees that are paged and maintained in a cache on a least recently used replacement basis. A fast sequence of events strategy increments the counts for events at the current node of the predictor.