Abstract: Provided is an IP data transmission apparatus using a legacy transmission system and a broadband downstream transmission system in a HFC network. The IP data transmission apparatus includes: an headend unit for receiving data from an application server system that is a service providing apparatus, splitting the received data into general user data and management message, determining whether the general user is transmitted using a broadband or an existing service band, and transmitting the general user data through the HFC network; and a user cable terminal unit for receiving the split data transmitted from the headend unit through the HFC network, transmitting the received data to an IP based user device, and transferring the management message to the IP based user device through the legacy transmission system.

Abstract: A Reed-Solomon (RS) decoding apparatus having high error correction capability and a method thereof are provided. The apparatus includes: error location and analysis polynomial generating units for performing a modified Euclid algorithm by receiving syndrome data upon receipt of an enable signal, and suspending input of the syndrome data and outputting error location polynomial data and error analysis polynomial data by executing the modified Euclid algorithm independently upon receipt of a disable signal; a controlling unit for controlling the error location and analysis polynomial generating unit and the input of the syndrome data; and switching units for providing the syndrome data to corresponding error location and analysis polynomial generating unit upon receipt of the enable signal and controlling the input of the syndrome data upon receipt of the disable signal. The number of the switching units is identical to that of the error location and analysis polynomial generating units.

Abstract: Provided is a method and apparatus for controlling an event of a cable modem and reporting a status of the cable modem, the method including: determining whether to periodically allocate a transmission bandwidth of a CM-STATUS message with respect to an event occurrence of the cable modem; setting an event control encoding that includes information regarding whether to periodically allocate the transmission bandwidth; and generating a MAC Domain Descriptor (MDD) message containing the event control encoding to transmit the generated MDD message.

Abstract: A multi-stream encryption apparatus and method, and a host device for multi-channel recording of a plurality of fee-based broadcasting services in a Downloadable Conditional Access System (DCAS) are provided.

Abstract: Provided is a method and apparatus for effectively receiving channel bonded upstream burst data in a Hybrid Fiber Cable (HFC) network.

Abstract: Provided is an apparatus for a channel bandwidth allocation, the apparatus including: an information sorting unit to receive bandwidth allocation request information, to sort the received bandwidth allocation request information according to a priority, and to transfer any one of the sorted bandwidth allocation request information to a minislot allocation unit; and a calculation unit to apply a multiplier to a number of bytes, and to transfer, to the minislot allocation unit, the bandwidth allocation request information where a number of requested bytes is calculated, when the bandwidth allocation request information is byte-based bandwidth allocation request information, wherein the minislot allocation unit allocates a minislot based on the bandwidth allocation request information and predetermined setting information.

Abstract: A mutual authentication method in a Downloadable Conditional Access System (DCAS) is provided. The mutual authentication method may receive authentication-related information about authentication between an authentication unit and a security module (SM) from a Trusted Authority (TA), generate an authentication session key using the authentication-related information, transmit the authentication session key by the authentication unit to the SM through a Cable Modem Termination System (CMTS), and control a Conditional Access System (CAS) software to be downloaded to the SM from the authentication unit, when the authentication is completed by the authentication session key.

Abstract: Provided is an apparatus and method for providing a video service flow using a dual scheduler for a headend cable modem in a Hybrid Fiber Coax (HFC) network. The apparatus may include: a service flow processing unit to determine whether a packet corresponds to a registered video service flow, when the packet is received; and at least one channel transmitter to schedule a packet corresponding to the registered video service flow and a packet not corresponding to the registered video service flow so that a transmission rate of the registered video service flow is guaranteed, and to thereby transmit the packets.

Abstract: A terminal authentication apparatus and method in a Downloadable Conditional Access System (DCAS) is provided. The terminal authentication method may determine whether terminal authentication information, received from a DCAS terminal, is valid by referring to a database, may transmit DCAS image information and pairing information about the terminal authentication information to a user terminal, when the terminal authentication information is valid, and thereby may enable the DCAS terminal to set the user terminal based on the pairing information.

Abstract: Provided is a Downloadable Conditional Access System (DCAS) service providing method where a mutual authentication with respect to a DCAS host and an Authentication Proxy (AP) server is performed, operating environment information and host identification information, which are extracted by the AP server, are transmitted by the AP server to a Personalization Server (PS), image information is selected by referring to the host identification information, the operating environment information, and policy information agreed to by a Conditional Access System (CAS) server and the PS, the image information being transmitted by the PS to a code download server, and the image information is transmitted to the DCAS host, when access information of the image information is transmitted to the DCAS host through the PS and the AP server.

Abstract: A technology that may efficiently detect a duplicated Downloadable Conditional Access System (DCAS) host in a DCAS is provided.

Abstract: Disclosed are a method and an apparatus of transmitting packet filtering information. A DSG channel information management server included in a digital cable broadcasting transmission headend combines a packet address and information related to the packet address and generates the combined information to be a single file, the packet address being used for filtering packets received by a cable modem contained in a cable broadcasting receptor, for each data type. The generated file is transmitted from a CMTS to the cable modem through a packet having a designated address mutually agreed upon between the headend and the cable modem, the cable modem obtains information for selectively filtering the received packets, from the received file, and constructs a filter. Data selectively filtered through each constructed filter is transmitted to a corresponding process module included in the cable broadcasting receptor that processes broadcasting program information, conditional access information, and the like.

Abstract: A method of verifying a validity of a Secure Micro (SM) is provided. The method of verifying a validity of an SM, the method including: storing and maintaining a validity verification message used to verify the validity of the SM, the validity verification message being generated by a Trusted Authority (TA) based on unique information of the SM, and the SM and the TA sharing the unique information of the SM; and verifying the validity of the SM using the validity verification message and the unique information shared by the SM, when an SM client is executed.

Abstract: Provided is a method for securing cable modem (CM) following a Data Over Cable Service Interface Specification (DOCSIS) against physical security attacks. The method includes the steps of: a) classifying information to be stored in the DOCSIS CM based on a requirement degree of confidentiality and anti-alteration; b) storing the information in a non-volatile memory of the DOCSIS CM when the information is absolute confidential information, but processing a mechanism for deleting the information stored in the non-volatile memory in case that attacks by a hacker is sensed; c) storing the information in the non-volatile memory of the DOCSIS CM when the information is middle-level security information; and d) storing the information in a write-once (WO) memory of the DOCSIS CM when the information is absolute anti-alteration information.

Abstract: An apparatus for determining a downstream topology in a hybrid-fiber-coaxial network includes: a signal branching unit for branching a signal received from a cable modem termination system into a plurality of branched signals; a plurality of signal selecting units for selectively receiving a frequency band signal corresponding to a specific downstream channel among the plurality of branched signals; a downstream topology determining unit for analyzing a downstream ambiguity resolution frequency list contained in a channel information message of a downstream primary channel received from the cable modem termination system, collecting in parallel channel information messages with respect to a plurality of downstream channels, and determining a downstream topology at a high speed using the collected channel information messages; and a plurality of packet generating units for setting downstream channel frequency bands of the signal selecting units under control of the downstream topology determining unit, and sen

Abstract: A method of controlling a download load of a Secure Micro (SM) client in a Downloadable Conditional Access System (DCAS) is provided. The method of controlling a download load of an SM client including: analyzing version information of SMs and version information of SM clients to control the download load generated in the DCAS, the version information of the SMs and the version information of the SM clients being provided from an Authentication Proxy (AP) server, and the SM clients being installed in the SMs; determining a download policy associated with a download time of a target SM client for the SMs based on a result of the analysis; and providing the AP server with the determined download policy.

Abstract: A method of managing security-related information in a Downloadable Conditional Access System (DCAS) is provided. The method of managing security-related information in the DCAS, the method including: receiving a request for storage of identification information and security-related information from a target server, the security-related information being required to be securely maintained; transmitting a recovery key to the target server in preparation for a loss of the security-related information in the target server; receiving a request for recovery of the security-related information from the target server, when the security-related information is lost; encrypting the security-related information of the target server using the recovery key; and transmitting the encrypted security-related information to the target server.

Abstract: Disclosed are a method and apparatus of scheduling a bandwidth in a cable network. The method includes receiving variable information set according to a condition of a network, calculating a packet time slot value in which a delay time gain is maximized using the received variable information; setting an algorithm allocating a bandwidth between channels of the network using the packet time slot value, and operating a Cable Modem Termination System (CMTS) according to the algorithm.

Abstract: Disclosed is a downloadable conditional access system (DCAS) including a key request unit to transmit a key request message to an authentication server, an authentication request unit to request authentication from the authentication server based on a key response message received from the authentication server in response to the key request message, and a session establishment unit to establish a session with the authentication server, based on an authentication response message received in response to the authentication request.

Abstract: Provided are a Downloadable Conditional Access System (DCAS), and a channel setting method and a message format for a 2-way communication between a terminal and an authentication server in the DCAS. The DCAS may include: a verification unit to verify an electronic signature and an integrity with respect to a message received from the authentication server; an extraction unit to extract network access information of the authentication server from the message in which the electronic signature and the integrity are verified; and a channel setting unit to set a communication channel with the authentication server based on the extracted network access information.