Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric R&d Centre Europe B.v.

Romain Rollet

Christophe Mangin

David Mentre

Corinne Rosier

The present disclosure relates to a method for performing switching functions by a processing circuit of a switching device, the communication over the communication channel being organized according to successive first time slices and a second time slices, the processing circuit implementing a RTOS which in normal operation comprises a RTOS scheduler for scheduling a plurality of tasks having different priorities, said method comprising:

Method for performing switching function and switching device

A method for transmitting data in a computer network is provided, which comprises, at a first node of the network: receiving a computing puzzle from a puzzle server node of the network distinct from the first node; determining a solution to the puzzle for transmitting a message to a second node of the network distinct from the puzzle server node; and transmitting data to the second node, wherein the transmitted data comprises a message and the determined solution to the puzzle.

Computational puzzles against dos attacks

The invention relates to a method of processing messages in a Factory Automation, FA, architecture comprising a FA network comprising at least one device, and an external network, said method being implemented by a network probe and comprising: intercepting () a message issued from the external network and intended for a device among the at least one device of the FA network; classifying () the message among a predefined set of categories based at least on the device for which the message is intended; deciding () to issue an alert based at least on the category in which the message is classified.

Network probe and method of processing message

The invention relates to a method of processing in real-time a data stream exchanged between a source and a server over a telecommunications network, the method being carried out by a classifier, said classifier storing a first set of a least one test, and a list of existing TCP connections, the method comprising:

Method of processing data stream, computer program product and classifier for processing data stream

The invention relates to a method of requesting retransmission of a lost data packet initially transmitted by a multicast transmitter in a network, the multicast transmitted multicasting data packets in the network, said method being carried out by a first multicast receiver and comprising the following steps:

Requesting retransmission of data in a multicast network

A method of performing a real-time classification of a data stream exchanged between a client and a server over a telecommunications network, comprises: receiving a data segment of the data stream indicating a data offset; updating a bitmap table with the received data segment, wherein the bitmap table comprises a number of blocks of data, the data blocks being ordered by block sequence numbers in the bitmap table; after updating the bitmap table, performing measurements on a complete data block to obtain at least one measurement result without waiting for all the data blocks having block sequence numbers that are lower than the first block sequence number to be completed; performing a statistical analysis based on measurement results obtained for several complete blocks; classifying the data stream into one group among a plurality of groups, based on the performed statistical analysis at least.

Classification device and method of performing a real-time classification of a data stream, computer program product, and system

For classifying a TCP connection carrying HTTP traffic as trusted or untrusted, an analyzer device performs: detecting an HTTP request message of an HTTP session carried by the TCP connection; obtaining, from headers of the detected HTTP request message, information to build a signature of the HTTP session; comparing the built signature with signatures stored beforehand in a signatures database; classifying the TCP connection as trusted, when the built signature matches a signature that is stored beforehand in the signatures database and that is representative of a trusted HTTP client application; performing an authentication procedure, when the built signature does not match any signature stored beforehand in the signatures database, the authentication procedure requesting a user to provide authentication data; adding the built signature in the signatures database, when valid authentication data are provided by the user, the signature of the HTTP session being representative in the signatures database of a trusted HTTP client application, and classifying the TCP connection as trusted; and otherwise, classifying the TCP connection as untrusted.

Method and device for classifying TCP connection carrying HTTP traffic

A method allocating timeslots for transmission of data packets and REPORT messages in a communication network including plural logical links managed by a terminal, including: implemented at each cycle by the terminal receiving at least one REPORT message from at least one logical link, the REPORT message including an updated queue length expressed in timeslots of the logical link and, upon receiving the REPORT message, updating the image queue length, based on the updated queue length; allocating to logical links having non-zero image queue length at least one timeslot in a next cycle based on a theoretical transmission time for transmitting data packets or REPORT messages and based on a fraction of overhead associated with the transmission, until all timeslots of the next cycle are allocated or all image queue lengths are zero, and incrementing the theoretical transmission time of each logical link based on its required minimum bit rate.

Optimized dynamic bandwidth scheduler

The present invention relates to a method of authenticating a user in a communication system comprising a user terminal and an authentication server which is capable of storing two types of nonce values, namely dedicated nonce values unique in the system and common nonce values shared between users in the system. In the method the authentication server receives () from the user terminal an access request. Then the authentication server uses a predefined criterion for determining the type of a first nonce value to be sent to the user terminal as a response to the access request. In case the predefined criterion is fulfilled, then a dedicated nonce value is sent, otherwise a common nonce value is sent (). Then the authentication server receives () from the user terminal a response comprising a second nonce value and a response code to the first nonce value. The authentication server then determines whether the response code is correct and whether the second nonce value corresponds to the first nonce value.

Robust digest authentication method

A method for submitting a TCP segment stream to a in-line content analysis comprises: receiving from a TCP emitter a first TCP data segments stream corresponding to a given TCP connection between the TCP emitter and a TCP receiver; extracting and re-assembling a first byte stream from the TCP segment stream; passing a second byte stream, which is derived from the first byte stream, to a content analyser () adapted to perform a content analysis on the second byte stream; relaying to the TCP receiver a second TCP data segment stream with a byte stream content totally consistent with the byte stream passed to the content analyser. In order to keep the device () that implements the method as stealthy as possible, the second TCP data segment stream has the same number of data segments as the first TCP data segment stream, all segments in the second TCP data segment stream being of same size and having the same header as corresponding segments in the first TCP data segment stream.

In-line content analysis of a TCP segment stream

A method of managing the allocation to TCP connections of memory blocks of a TCP re-assembly buffer in a TCP network device including a TCP Processing unit, comprises computing a function r(t) on a per connection basis, that measures the occupancy rate of the re-assembly buffer for the relevant TCP connection, and that is updated upon reception of any packet belonging to said TCP connection; and allowing the TCP connection to be closed and the corresponding memory blocks to be released based on a decision scheme that includes at least a first trigger set on the corresponding function r(t), which defines two different states for said function r(t).

Protection of data transmission network systems against buffer oversizing

A method for transmitting a payload encapsulated in a packet from a transmitter to a receiver by using an Automatic Request process, in which: the receiver checks each packet received from the transmitter to detect some potential corrupted received packets the receiver acknowledges the correct or the corrupted reception of each received packet by emitting one or many acknowledgment messages to the transmitter; the transmitter resends the packets that were indicated as corrupted in the received acknowledgment messages. For at least some packets, the transmitter implements an EC-PartARQ error control mechanism including the steps of: defining a sensitive part and a non-sensitive part in the transmitted packet; checking only the sensitive parts in the packets to detect any potential corrupted received packet, a packet being considered as corrupted if the sensitive part has not been correctly received.

Method for transmitting data including an error control mechanism designed for unreliable networks and error resilience applications

There is disclosed a method of transferring input data packets from an upper layer to a lower layer of a stack of communication protocol layers, wherein the lower layer supports variable sized packets. One input data packet is received from the upper layer. This input data packet is segmented into several data segments the size of which is selected in a list of a given number N of predetermined segment size values. Signalling information is added to each data segment to form output data packets, which is delivered to a lower layer. Selection of the segment size value is performed according to an algorithm which minimizes the overall ineffective data and/or the overall signalling information. Thus, the transmission overhead generated by the segmentation scheme is reduced.

Methods and devices for transferring and for recovering data packets

A method and a device of address management in a network which comprises a plurality of devices, including at least one STAtion (STA), and at least one Address Resource Management (ARM) unit. Each of the devices includes a stack of communication protocol layers comprising at least an Upper Layer (UL) and a Lower Layer (LL). The UL of each of the devices has a respective UL address within the network. The ARM unit associates, respectively disassociates, some of the devices in at least one LL network. The devices of a given LL network are allowed to exchange together data packets emitted and received at the LL level. The ARM unit allocates, respectively releases, one given LL address per each associated device, respectively disassociated device, in a given LL network. Besides, the ARM unit handles one ARM Translation Table (TT) per LL network. The TT comprises one entry per device of a given LL network and each entry comprises the UL address and the LL address.

Method and device address management

There is disclosed a method and a device of controlling transmission errors in a network comprising at least one transmitter, at least one receiver and a Radio Resource Management (RRM) unit for allocating transmission resource dedicated to the transmitter and/or the receiver. A FeedBacK (FBK) function is introduced to manage transmission of feedback information which is transmitted by the receiver to the transmitter to indicate transmission errors. The FBK function comprises a transmitter FBK instance and a receiver FBK instance. At first, the transmitter FBK instance transmits Protocol Data Units (PDUs) to the receiver FBK instance. The FBK function monitors transmission errors on the receiver FBK instance side and/or on the transmitter FBK instance side to determine a transmission quality level out of a set of given transmission quality levels. The FBK function selects one feedback operational mode out of a predetermined list of feedback operational modes based on the determined transmission quality level, each one of feedback operational modes defining a feedback resource allocation scheme for the transmitter FBK instance and the receiver FBK instance. The receiver FBK instance transmits to the transmitter FBK instance feedback information via a resource allocated based on the selected feedback operational mode.

Growing community of inventors

Rennes, France

Romain Rollet