• Proceedings of the KIEE Conference
• /
• 1998.07g
• /
• pp.2473-2475
• /
• 1998

In this paper, we implemented RS232C serial communication by the 2 wires(Data,GND), and multiple access, by the applying Collision Sensing Multiple Access(CSMA) Protocol. Multiple access is implemented by assigning a unique ID to each controller. The multiple access control operation starts by sending a command packet from a host to another host and the command packet is composed of ID bytes of source and target host computer, data bytes and the check sum, byte. In host computer, after sending command packet, the collision from loop back data. If collision is detected, it means a command packet was collided with another command packet for another host. The packet communication of the controller enables the multiple acces of the controller through the common serial data link. The application of this serial communication through CSMA protocol and the usage of two wires, have an effect on saving the wires and convenient of layout work.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2003.10a
• /
• pp.542-547
• /
• 2003

A network based intrusion detection system(N-IDS), can detect intruders coming in through packets in real time environment. The ability of capture of packet is the most important factor when we evaluate the performance of the system. The time delay between the time handling one packet capture and next one is variant become of packet handling mechanism. So for N-IDS can not settle this problem because most systems use a single processor. In this thesis, we solve the problem of irregular tine delay with a file socket and multi-thread processing. We designed and implement, the Crasto system. By an accurate observation, the performance testing shows that the Crasto reduces the capture delay time to 1/5 comparing to the existing single process N-IDS, and maintain delay time regularly.

• The Journal of the Korea Contents Association
• /
• v.3 no.1
• /
• pp.21-30
• /
• 2003

Retracing schemes using packet marking are currently being studied to protect network resources by isolating DDoS attack. One promising solution is the probabilistic packet marking (PPM). However, PPM can't use ICMP by encoding a mark into the IP identification field. Likewise, it can't identify the original source through a hash function used to encode trace information and reduce the mark size. In addition, the retracing problem overlaps with the result from the XOR operation. An algorithm is therefore proposed to pursue the attacker's source efficiently. The source is marked in a packet using a router ID, with marking information abstracted.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2010.10a
• /
• pp.229-232
• /
• 2010

Smart Phone is the increasing use. Smart Phone can be run on that New or videos you want to connect to the Internet for downloading and viewing applications. But the wireless Internet have been found that Due to the vulnerability of the Internet, Smart Phone security vulnerabilities. This paper analyzes the vulnerability. Smart Phone droid that occur when connecting to the Internet. For information on Smart Phone to use to analyze network packet analysis and packet capture tools. Analysis is based on information from the Internet when you use Smart Phone Hack will demonstrate the process. Messenger, ID, to confirm the password, the actual internet ID, password access to the personal information that can be seized. In this study, hacking and security of the Smart Phone will contribute to the research process that Internet information and communication powers to strengthen the security of Korea.

• Proceedings of the IEEK Conference
• /
• 2002.07c
• /
• pp.1602-1605
• /
• 2002

Communication schemes are currently changing from circuit switched towards packet switched. These changes enable access to Internet and multimedia services in wireless network. Provision of real-time IP services in air interface introduces relatively large overhead in RTP/UDP/IP headers. To reduce the overhead, the header compression schemes are required. There exist two header compression schemes (CRTP, ROHC) which are IETF standards. We propose Context-ID detection method which reduces more efficiently the packet loss rate than two existing schemes. Its performance in WCDMA system environment is evaluated for CRTP and ROHC schemes.

• The Journal of the Korea Contents Association
• /
• v.5 no.5
• /
• pp.78-84
• /
• 2005

Various kinds of data broadcasting services can be offered using a return-channel in digital broadcasting TV compared to analog services. In these data broadcasting environments, several data(associated with TV broadcasting programs, or not) are provided to the TV audiences except for audio/video broadcasting data. In this paper, a structure of data manager for data/object carousel, based on data broadcasting protocols, was proposed for data broadcasting services using a return-channel, and were supported to the production technologies of DTV contents. These contents application techniques for DTV will be implemented with this data manager in MPEG2-TS data broadcasts using PID(Packet ID).

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.31 no.6
• /
• pp.1279-1290
• /
• 2021

As vehicle technology has grown, autonomous driving that does not require driver intervention has developed. Accordingly, CAN security, an network of in-vehicles, has also become important. CAN shows vulnerabilities in hacking attacks, and machine learning-based IDS is introduced to detect these attacks. However, despite its high accuracy, machine learning showed vulnerability against adversarial examples. In this paper, we propose a adversarial CAN frame generation method to avoid IDS by adding noise to feature and proceeding with feature selection and re-packet for physical attack of the vehicle. We check how well the adversarial CAN frame avoids IDS through experiments for each case that adversarial CAN frame generated by all feature modulation, modulation after feature selection, preprocessing after re-packet.

• The KIPS Transactions:PartC
• /
• v.11C no.3
• /
• pp.301-308
• /
• 2004

Misuse IDS is known to have an acceptable accuracy but suffers from high rates of false alarms. We show a behavior based alarm reduction with a memory-based machine learning technique. Our extended form of IBL, (XIBL) examines SNORT alarm signals if that signal is worthy sending signals to security manager. An experiment shows that there exists an apparent difference between true alarms and false alarms with respect to XIBL behavior This gives clear evidence that although an attack in the network consists of a sequence of packets, decisions over Individual packet can be used in conjunction with misuse IDS for better performance.

• Proceedings of the KIEE Conference
• /
• 2000.07d
• /
• pp.2971-2973
• /
• 2000

In this paper, we proposed the implementation of multiple access serial communications with improved transmission control. For serial communications. RS232 protocol is used and the transmitting data and is merged to form data channel. Multiple host access is configures by using the common data channel and ground channel. 8bit data transfer with variable frame size is transferred by using the 16bit host ID. Packet is composed of HEADER, receiver ID. variable length data frame, TAIL and CRC informations. Multiple hosts are allowed to transfer packet with the other hosts through the common communication channel. Byte-stuffing is used to differentiate the transfer rate of PC is performed.

• Journal of Information Processing Systems
• /
• v.14 no.6
• /
• pp.1347-1360
• /
• 2018

Owing to limited energy in wireless devices power saving is very critical to prolong the lifetime of the networks. In this regard, we designed a cross-layer optimization mechanism based on power control in which source node broadcasts a Route Request Packet (RREQ) containing information such as node id, image size, end to end bit error rate (BER) and residual battery energy to its neighbor nodes to initiate a multimedia session. Each intermediate node appends its remaining battery energy, link gain, node id and average noise power to the RREQ packet. Upon receiving the RREQ packets, the sink node finds node disjoint paths and calculates the optimal power vectors for each disjoint path using cross layer optimization algorithm. Sink based cross-layer maximal minimal residual energy (MMRE) algorithm finds the number of image packets that can be sent on each path and sends the Route Reply Packet (RREP) to the source on each disjoint path which contains the information such as optimal power vector, remaining battery energy vector and number of packets that can be sent on the path by the source. Simulation results indicate that considerable energy saving can be accomplished with the proposed cross layer power control algorithm.