Abstract: One or more flow control modules, implemented on various types of network topologies, provide a number of functionalities for controlling the flow of IP packets (such as TCP/IP packets) over a network connection. The flow control modules may be implemented within a sender and/or receiver or may be deployed into a network as a separate device without requiring significant additional resources.

Abstract: Network endpoints using TCP/IP operate to determine the maximum transmission unit (MTU) of the path between them. This determination is done so as to avoid the expensive IP fragmentation that will occur when transitting links with a smaller MTU size. The standard method of determining the path MTU (PMTU) has several known deficiencies, including: inefficient use of bandwidth as proper operation will likely result in the loss of one or more packets and difficulty of implementation as the reverse channel communication mechanism, reception of ICMP messages indicating the discarding of unfragmentable packets, is frequently blocked by firewalls and other security apparatus. A method of determining the PMTU between intermediate proxies is disclosed that does not require reception of ICMP messages or the inefficient use of bandwidth due to the presumed dropping of packets with valid data.

Abstract: A user can access database documents across category hierarchies by executing a computer program that operates on a pre-computed intersection list. The intersection list comprises a plurality of report keys which are generated off-line by combining index terms in database documents with category descriptors to form text strings having a name/value type format. All report keys from all documents are combined and sorted to determine a set of unique report keys. Each unique report key is updated with a count of the number of documents sharing the same report key. Additionally, each updated report key includes a pointer to a bit-map corresponding to the lowest level category in a category hierarchy. The updated report keys are resorted to provide an intersection list for retrieving document information from databases and other information sources in response to the user's online search queries.