Abstract: A method and system that reduces the impact of packet loss on video data quality. Packet selection is performed by the method and system to selectively drop low priority packets so that the overall quality of the received video data may be improved. In one exemplary embodiment, the probability of higher priority layers being delivered on time is computed and a packet is transmitted only if this probability is greater than a given threshold h. In another exemplary embodiment, the system and method have the capability of backing up the process to transmit previously skipped packets, if time allows.

Abstract: An IP-based corporate network architecture and method for providing seamless secure mobile networking across office WLAN, home WLAN, public WLAN, and 2.5G/3G cellular networks for corporate wireless data users. The system includes Internet roaming clients (IRCs), a secure mobility gateway (SMG), optional secure IP access (SIA) gateways, and a virtual single account (VSA) server. The IRC is a special client tool installed on a mobile computer (laptop or PDA) equipped with a WLAN adaptor and a cellular modem. It is responsible for establishing and maintaining a mobile IPsec tunnel between the mobile computer and a corporate intranet. The SMG is a mobile IPsec gateway installed between the corporate intranet and the Internet. It works in conjunction with the IRC to maintain the mobile IPsec tunnel when the mobile computer is connected on the Internet via a home WLAN, a public WLAN, or a cellular network.

Abstract: New oxide phosphors based on gallium-indium oxide for electroluminescent materials. Bright red emission has been obtained using Ga2-x-yInxEuyO3 wherein x spans the range 0.1 to 0.4 and y spans the range in which it is soluble in the phosphor.

Abstract: A fast authentication and access control method of authenticating a network access device to a communications network having an access point communicating with a remote authentication (home AAA) server for the network access device. The method includes the step of receiving an access request having an authentication credential from the network access device at the access point. The authentication credential includes a security certificate having a public key for the network access device and an expiration time. The security certificate is signed with a private key for the remote authentication server. The access point locally validates the authentication credential by accessing the public key of the remote authentication server from a local database, and checking the signature and expiration time of the security certificate.

Abstract: A wireless network includes a plurality of proxy servers located at various locations to selectively transform data based upon network conditions, such as link congestion. A queueing model for the network can be used to determine optimal operating parameters for the network.

Abstract: A Virtual Single Account (VSA) system and method that provides a mobile user with automatic authentication and connection to a remote network via local access networks with a single password, where the local access networks may be independent of the remote network. A mobile user has a single authentication credential for one VSA that is utilized by a VSA client installed on a mobile computing device. The VSA client provides for automatically authenticating and connecting the user's mobile device to a current local access network, and the target remote network such as the user's office network. All authentication credentials are encrypted using a key generated from the user's VSA password that is generated from the user's single password. The VSA client derives the key from the submitted VSA password and decrypts all authentication credentials that are required in order to connect the mobile device to the current local access network and thereafter to the office network.

Abstract: A method and apparatus to enable IP networking for mobile hosts without requiring changes to be made to the TCP/IP stack in the operating system installed on the mobile hosts. The apparatus is an “intelligent device” that can be installed on or connected to a mobile host, and may comprise a software-only logical module, physical hardware, or a combination of both. To a mobile host, the intelligent device emulates a network interface such as an Ethernet card or a telephone modem. The intelligent device appears to an access network just like any regular IP host connected to the access network through a physical network interface device. The intelligent device handles all mobile networking functions for the mobile host, and may control multiple different physical network interface devices to enable a connection to the “best” access network available to the mobile user at his location.

Abstract: The present packet scheduling algorithm gives cellular network operators greater flexibility in adjusting the way resources are allocated among interactive best-effort data users. Best effort data users with different radio link qualities may have different amounts of data delivered to them using the same amount of radio resource. In the context of link adaptation, this characteristic complicates the fairness issue in cellular environments and has a profound impact on the overall system performance. As a result, the present packet scheduling algorithm is capable of allocating radio resource dynamically, not only based on channel conditions, but also to achieve different performance trade-offs among users with different link qualities. According to the algorithm, channel quality is determined for each user, channel efficiency is calculated and the channel efficiency value is used as the primary factor in weighting the delivery of packets to (or from) a given user.

Abstract: A Virtual Single Account (VSA) system that provides a mobile user with automatic authentication and connection to a remote network via local access networks with a single password, where the local access networks may be independent of the remote network. A mobile user has a single authentication credential for one VSA that is utilized by a VSA client installed on a mobile computing device. The VSA client provides for automatically authenticating and connecting the user's mobile device to a current local access network, and the target remote network such as the user's office network. All authentication credentials are encrypted using a key generated from the user's VSA password that is generated from the user's single password. The VSA client derives the key from the submitted VSA password and decrypts all authentication credentials that are required in order to connect the mobile device to the current local access network and thereafter to the office network.

Abstract: A fast authentication and access control method of authenticating a network access device to a communications network having an access point communicating with a remote authentication (home AAA) server for the network access device. The method includes the step of receiving an access request having an authentication credential from the network access device at the access point. The authentication credential includes a security certificate having a public key for the network access device and an expiration time. The security certificate is signed with a private key for the remote authentication server. The access point locally validates the authentication credential by accessing the public key of the remote authentication server from a local database, and checking the signature and expiration time of the security certificate.

Abstract: A method and system that reduces the impact of packet loss on video data quality. Packet selection is performed by the method and system to selectively drop low priority packets so that the overall quality of the received video data may be improved. In one exemplary embodiment, the probability of higher priority layers being delivered on time is computed and a packet is transmitted only if this probability is greater than a given threshold h. In another exemplary embodiment, the system and method have the capability of backing up the process to transmit previously skipped packets, if time allows.

Abstract: The present invention is based on a prefetching scheme consisting of two modules: a prediction module and a threshold module. After a use's request for a new file is satisfied, the prediction module immediately updates a database of history information if needed, and computes the access probability for each candidate file, where the access probability of a file is an estimate of the probability with which that file will be requested by the user in the near future. Next the threshold module determines the prefetch threshold for each related server, which contains at least one candidate file with nonzero access probability. The threshold is determined in real time based on then current network conditions. Finally, each file whose access probability exceeds or equals its server's prefetch threshold is prefetched. When prefetching a file, the file is actually downloaded if and only if no up-to-date version of the file is available on the local computer; otherwise no action is taken.

Abstract: The present packet scheduling algorithm gives cellular network operators greater flexibility in adjusting the way resources are allocated among interactive best-effort data users. Best effort data users with different radio link qualities may have different amounts of data delivered to them using the same amount of radio resource. In the context of link adaptation, this characteristic complicates the fairness issue in cellular environments and has a profound impact on the overall system performance. As a result, the present packet scheduling algorithm is capable of allocating radio resource dynamically, not only based on channel conditions, but also to achieve different performance trade-offs among users with different link qualities. According to the algorithm, channel quality is determined for each user, channel efficiency is calculated and the channel efficiency value is used as the primary factor in weighting the delivery of packets to (or from) a given user.