Electronics and Telecommunications Research Institute

Korea Advanced Institute of Science and Technology

Korea Telecommunication Authority

Song In Choi

Jee Hwan Ahn

Junghak Kim

Man Ho Park

Dae Sik Kim

Byung Sik Yoon

Hyoung Jung Kim

In Sung Lee

Jong Hark Kim

Young Sun Kim

Tae Whan Yoo

Jung Hak Kim

Sook Jin Lee

Hong Sun Park

Ki Chul Han

Byung Wan Lim

Myoung Ho Kim

Ji Hwan Song

Won Myoung Lee

A lawful interception apparatus of a service providing system inquires of a trust server in which a law execution server commissions lawful interception authority whether a terminal that connects to a service connection point is an interception target, determines whether a terminal that connects to a service connection point is an interception target, and if a terminal that connects to a service connection point is an interception target, and the lawful interception apparatus intercepts communication traffic that is related to the terminal.

Apparatus and method for lawful interception

A string matching device extracts a string by shifting a start position from an input data stream, compares the extracted string with a sub-string included in a target string, and when a prefix of a target string is detected from the string extracted from the input data stream, it selects one of the strings output in the next stage based on the start position of the corresponding string and uses it to detect the sub-string. Also, the device can consecutively detect at least one target string from the input data stream by using a state transition process.

String matching method

A pattern matching system detects strings contained in a target pattern to be detected within a data stream input by 1-byte data, and detects a regular expression representing the target pattern among regular expressions constructed by the detected strings.

System and method for matching patterns

In a lawful interception system including an interception unit, an application service providing unit, and an Internet access service providing unit, the application service providing unit may receive, from the interception unit, an interception request including interception target information of an interception target. Next, the application service providing unit may transfer a user code corresponding to the received interception target information to the interception unit, and may insert user related information into a packet to be provided to the interception target corresponding to the user code, enabling the packet to be lawfully intercepted. The interception unit may request the Internet access service providing unit for an interception of the packet with respect to the interception target by including the user code.

Method and system for lawful interception of internet service

The present invention relates to an apparatus and method of classifying packets that can support a quality of service (QoS) in a network system. An apparatus for classifying packets according to an exemplary embodiment of the present invention includes: a first unit that analyzes input data packets, extracts pluralities of specific fields from the data packets using an analyzed result, and outputs the pluralities of specific fields; pluralities of second units that compare data of a first portion of the pluralities of extracted specific fields with data in a table, determine whether items that satisfy a predetermined condition exist in the table, and output hit signals and pointers indicating positions of the items that satisfy the predetermined condition when the items that satisfy the predetermined condition exist in the table; and a third unit that compares data of a second portion of the pluralities of extracted specific fields and key data including the pointers input from the pluralities of second units and rule data in a rule table and outputs classes corresponding to the items when the key data and the rule data are matched.

Apparatus and method of classifying packets

The present invention relates to a data processing method and system for checking an interactive communication sequence (ICS) relating to a plurality of users in a communication record by using a variable time window, and checking an interactive communication sequence pattern (ICSP) that is a frequently generated interactive communication sequence from among the checked interactive communication sequences. The data processing method includes: (a) storing an inverse pair in a communication record in an interactive communication sequence set or a candidate set that is a set of inverse pairs that can be part of the interactive communication sequence; (b) generating an interactive communication sequence having a length other than 1 by combining interactive communication sequences included in the interactive communication sequence set; and (c) generating an interactive communication sequence having a length other than 1 by combining the inverse pair included in the candidate set and one of the interactive communication sequence included in the interactive communication sequence set of (a) and the interactive communication sequence generated in (b).

Method for processing data to check an interactive communication sequence and system thereof

The present invention relates to a harmonic-noise speech coder and coding algorithm of the mixed signal of voiced/unvoiced sound using harmonic model. The harmonic-noise speech coder comprises a noise spectral estimating means for coding the noise component by predicting the spectral by LPC analysis method after separating the noise, which is unvoiced sound component from the inputted LPC residual signal using cepstrum. And more improved speech quality can be obtained by analyzing noise effectively using the noise spectral model predicted through cepstrum-LPC analysis method of the mixed signal of voiced/unvoiced sound to the existing harmonic model and then coding the signal.

Harmonic-noise speech coding algorithm and coder using cepstrum analysis method

A time-separated speech coder that codes a transitional signal of voiced/unvoiced sound through harmonic speech coding, the coder including a transitional excitation signal analyzer/synthesizer for coding the transitional signal by extracting the harmonic model parameters of both transitional analyzers after detecting a transitional point and generating sinusoidal waveforms according to a variable transitional point separating both transitional analyzers. By the transitional point at which energy varies abruptly and the time-separated coding based on the transitional point, more improved speech quality than in the general harmonic speech coder can be obtained using the time-separated speech coder by increasing the representation capability of the transitional signal with large energy variation, after adapting it to the variable transitional point.

Speech coding system and method using time-separated coding algorithm

There is disclosed an echo cancelling apparatus in a digital mobile communication system and method thereof, which is incorporated in a single chip together with a speech coder, and can improve convergence rate by using an excited signal as an input to n adaptive filter and also obtain a stabilized convergence characteristic while using a NLMS algorithm. The echo canceller according to the present invention uses the excited signal obtained at the speech coder as an input signal to an adaptive filter thereby to lower the Eigenvalues distribution rate of the speech signal, thus providing an improved performance compared to the conventional echo canceller.

Echo cancellation apparatus in a digital mobile communication system and method thereof

A parallel distributed sample descrambler part for a cell-based ATM physical layer, comprising a PRBS generator for generating an 8-bit random number when being set to any value other than '0' in response to an initial value set signal upon initialization, to execute a generation polynomial for distributed sample descrambling given by x.sup.31 +x.sup.28 +1, and a descrambler for adding 8 bits of reception data to 8 bits of the random number from the PRBS generator, respectively, to perform the descrambling of the reception data and outputting the descrambled data bits. A sample processor extracts two bits for synchronization of the descrambler from the 8-bit random number from the PRBS generator as first and second samples in response to an external sampling clock and an external synchronous clock. The sample processor also extracts highest first and second bits of a syndrome signal from a cell delineation part in a cell-based ATM physical layer receiver as transmitter PRBS samples in response to the external sampling clock and the external synchronous clock. The sample processor compares the extracted first and second samples and the extracted syndrome signal highest first and second bits with each other and outputs first and second synchronous signals for the PRBS generator in accordance with the compared result.

Growing community of inventors

Daejeon, South Korea

Song In Choi