Abstract: In a method of establishing a data connection between a client computer and a destination computer over a computer network, a first computer network comprises a local area network (LAN) to which is connected a first, second and third client computer. At the boundary of the first computer network is provided a first firewall computer which is connected to the LAN. The first firewall computer is a secure relay computer. A second computer network comprises a web-site server and a second firewall computer which acts in much the same way as the first firewall computer. The second firewall computer only permits incoming data connections if an SSL data connection is used. The second computer network is connected to the first computer network by means of a public network, in this case the Internet. Each of the first, second and third client computers is able to access a website stored on the web-site server.

Abstract: In a method of establishing a secure data connection, a corporate computer network comprises a LAN to which is connected a first, second and third client computer. At the boundary of the corporate computer network is a firewall computer (hereinafter simply referred to as ‘the firewall’). The firewall is configured to prevent incoming data connections being made to the LAN from outside of the corporate computer network. As well as preventing incoming communications with the LAN, the firewall is also configured to control connections requested from within the corporate computer network to external computers. Indeed, for security purposes, the firewall is configured to require authentication of such requests for an external connection (i.e. to verify who is anally making the request) prior to establishing the external connection. This authentication is performed using the SSL protocol. In this case, the Java Secure Sockets Extension (JSSE) version of SSL is used.

Abstract: A two way radio communication system (20) includes a plurality of radio units (22, 24, 26, 28, 30) communicating via at least one communication resource (34, 36). At least one first radio unit (22, 24, 26, 28, 30) of the plurality of radio units includes a receiver (48) for monitoring available resources of the at least one communication resource (34, 36) and a processor (46) for maintaining a prioritized list (45) of said available at least one communication resources and for selecting the highest priority available communication resource when the at least one radio unit (22, 24, 26, 28, 30) wishes to enter into communication with at least one second radio unit of the plurality of radio units. In this manner, an optimized communication resource is selected for the communication.

Abstract: A method is disclosed for determining current channel state information in a communications system having a first communications unit communicating to a second communications unit, wherein the first communications unit sends a channel sounding packet (32) to the second communications unit. The channel sounding packet (32) is sent a time period, t, prior to the transmission of a signal by the second communications unit to the first communications unit. The second communications unit receives the channel sounding packet (46) and processes the channel sounding packet to determine at least one channel characteristic. In response to receiving the channel sounding packet (46) the second communications unit appends frame code information (48) to the signal to be transmitted from the second communications unit to the first communications unit, to inform the first communications unit of the communications parameters that have been optimized.

Abstract: A radio communications apparatus employs a training routine for optimizing performance and has a modulator (64, 66) to modulate a radio channel with digital information, to provide baseband signals (I, Q) at a first data rate. A power amplifier (36) amplifies signals fed from the modulator. A feedback loop (40, 42, 44, 30) samples the output signals of the power amplifier and adjusts at least one of the amplitude and phase of the baseband signals to compensate for distortion introduced by the power amplifier. The data rate of the baseband signals is reduced during the training routine to reduce adjacent channel transmissions.

Abstract: Apparatus for automatically feeding sheet material such as fan fold paper to a photocopier in which the apparatus may be movable towards and away from the window of the photocopier either by disconnecting the apparatus completely from the photocopier by means of readily releasable clamps or by pivoting part of the apparatus away from the window of the photocopier whereby the apparatus may be used not only to photocopy fan fold paper but used in a conventional manner to photocopy normal documents. Control signals to operate the apparatus are derived by a light sensitive means viewing the light source within the photocopier through the window of the photocopier.