• Journal of the Korean Institute of Telematics and Electronics A
• /
• v.33A no.11
• /
• pp.32-43
• /
• 1996

In this paper we wanted to implement a reliable ISDN PABX that could maintain the user's voice and data communication services, even when there might be an unexpected system error. In order to implement the fault-tolerance we made this ISDN PABX composed of an active and a standby side by duplicating the main control parts. Whenever a critical error occurs in the active side, it makes side exchange so that the standby side as anew active side continues to proceed the currently active voice or data services. Finally, through the performance evaluation we proved that user's voice or data communication can be serviced without any sense in spite of an system error.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.15 no.5
• /
• pp.413-425
• /
• 1990

In this study, we propose a separated type concentrator to accommodate 2B+D ISDN basic access traffic. This system's blocking probabilities are analyzed in terms of each class of bit rate, number of output channels, number of subscriber lines, and offered traffic. The result shows that the proposed method can significantly increase the maximum number of subscriber lines connecting to the system via a T1 crrier, compared with that of the "CCITT proposed" multiplexing scheme.ng scheme.

• Korean Management Science Review
• /
• v.10 no.1
• /
• pp.107-125
• /
• 1993

Modern telecommunication switching systems are SPC(Stored Program Control) machines handling voice, data and other kinds of traffic, in an environment which tends to be fully digital switching and transmission. The throughput of such systems is determined by the real time capacity of its centralized or distributed control processors and by the traffic capacity of the switching network. Designers must verify the traffic and call processing capacity of the switching system and check its performance under traffic load before it is put into service. Verification of traffic and call processing capacity of switching systems is one of the problems treated by teletraffic studies ; teletraffic studies are based on stochastic process, queueing theory, simulations and other quantitative methods of decision making. This study suggests the general methodology to evaluate the throughput and performance of the ISDN switching system. TDX-10 ISDN switching system are employed to give illustrative examples of the methodologies discussed in this study.

• Journal of the Korean Institute of Telematics and Electronics A
• /
• v.30A no.11
• /
• pp.29-39
• /
• 1993

For an economical or timely reason, the types of subscriber loops for ISDN basic rate access service will, at least initially, be that of the pre-existing telephone network, that is, 2-wire twisted-pair metallic cable. Therefore, it is important to assess the high-speed digital transmission capability of the 2-wire subscriber loops. In this paper, the impairments such as intersymbol interference, crosstalk, and impulse niose are modeled. And then, symbol error probabilities in terms of SNR in DSL system using ECH and 2B1Q line code are analytically derived and numerically calculated. Also, the relationship between the quality of service required in ISDN subscriber section and the loop parameters is investigated.

• Electronics and Telecommunications Trends
• /
• v.10 no.1 s.35
• /
• pp.101-111
• /
• 1995

정보화의 진전으로 정보가 경제활동에 있어서 새로운 추구대상이 되고 있으며, 산업과 사회전반에 걸쳐 정보통신의 이용이 확대되고 있다. 정보통신의 산업적 활용은 생산, 유통방식의 변화와 함께 "산업의 정보화"를 통한 생산성 향상 등 기업활동에 변화를 초래하고 있다. 그 결과 21C 국가경쟁력은 정보통신의 효율적 활용에 의해 좌우될 것이라는 인식하에 각국은 범국가적 차원에서 정보통신의 기반구조로서 B-ISDN구축사업을 실행하고 있으며, 우리나라도 초고속정보통신망의 구축을 위해 2015년까지 총 44.8조원의 투자를 계획하고 있다. 본 고에서는 정보통신의 산업적 역할과 영향분석을 통해 B-ISDN 구축에 따른 산업 및 경제적 성과를 조명해 보고자 한다.

• Electronics and Telecommunications Trends
• /
• v.14 no.5 s.59
• /
• pp.1-15
• /
• 1999

본 고에서는 B-ISDN 망의 NNI 프로토콜로 B-ISUP과 PNNI가 동시에 수용되는 공중 망에서 ITU-T E.164 주소체계 사용에 따른 장.단점을 살펴보고, 공중망 교환기에 ATM Forum 신호 권고안을 수용하면서 지금까지 주로 사설 ATM 망에서 사용되어 온 AESA DCC, ICD/IOTA 주소체계를 공중망에 수용하기 위한 검토사항, 필요성, 수용방법을 기술하고, 국내에서 구축중인 B-ISDN 망의 AESA DCC, ICD 주소형태(address format) 및 각 주소계위(address hierarchy)의 의미, 이를 지원하기 위한 공중망 교환기의 기능에 대하여 기술하고자 한다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.13 no.1
• /
• pp.19-27
• /
• 1988

In the user-network interface for the parcticing ISDN, an effective phase aligned time compression multiplexing transmission system is designed and analyzed in the 2 wire passive BUS. In TCM, tha average SNR due to crosstalk from adjacent channelis 9.72(dB), and in regarding the phase aligned process, frames are designed to have maximum propagation time of 6(us) so that the connection distance is extended by 0.8(Km). Therefore, the proposed transmission system is suitable for the connection between end-subscriber and network.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.1 no.2
• /
• pp.137-143
• /
• 1997

From now on, the network is being developed into PSTN(public switched telephone network) and PDN(public data network), that is depend on the form of data. The former one pursues sending voice, and the latter one pursues sending data. But it causes big loss of the economy and efficiency. So, ISDN, processing voice and data at same time, gives a big profit to user. To enlarge the ISDN at the narrow area, it is necessary that study to send the mixture form of voice and data in LAN environment. So, this paper proposes the algorithm about the mixture form of voice and data in ethernet and token-ring. that is widely used in these days.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2001.04a
• /
• pp.499-502
• /
• 2001

음성, 데이터 및 영상 등의 모든 정보를 주고받을 수 있는 멀티미디어 통신 서비스는 여러 가지 형태의 가입자망 구축으로 가능하나 유선 가입자망 구성에서 대표적으로 ISDN, ADSL 및 케이블모뎀 등을 들 수 있다. 본 논문에서는 ISDN 망에서 멀티미디어 통신 서비스를 제공하기 위해 구현된 통신 단말의 운용모드에 대해 검토한 후 단말의 하드웨어 구성 요소와 음성 및 데이터 서비스를 위한 통신 단말의 소프트웨어 구조 및 서비스 절차에 대해 기술한다.

• ETRI Journal
• /
• v.9 no.4
• /
• pp.36-49
• /
• 1987

통신망이 ISDN으로 진화되어감에 따라 전송분야에서 요구되어지는 새로운 기술 및 기능에 대하여 고찰하였다. 단기적으로는 디지틀 가입자 전송 및 64kbps 완전채널 기능, 장기적으로는 회선의 분기/분배 기능, 광가입자 관련기술 및 광대역 비동기식 다중기능 등이 요구될 것으로 전망된다.