• ETRI Journal
• /
• 제19권3호
• /
• pp.141-168
• /
• 1997

The base station (BS) in the CDMA Mobile System (CMS) connects calls through the radio interface and is designed to provide mobile subscribers with high quality service in spite of mobile subscribers motions. The BS consists of multiple base station transceiver subsystems (BTSs), a base station controller (BSC) and a base station manager (BSM). This paper is concerned with the BSC and the BSM. The BSC is located between the BTSs and the mobile switching center (MSC) connected with the public network, and to mobile subscribers via the BTSs. The BSM provides operator-interfaces per the BS and takes responsibility of operation and maintenance (OAM) of the BS. Design of the BSC is based on two module types: functional module and unit module. The functional module is used to support new services easily and the unit module to increase the system capacity economically. Both modular types are easily achieved by inserting the corresponding modules to the system. Particularly, in order to efficiently support the soft handover which is one of CDMA superior advantages, the BSC adopts a large high-speed Packet switch connecting up to 512 BTSs, and thus mobile subscribers can be provided with soft handover in high probability. The BSM is based on a commercial workstation to support OAM functions efficiently and guarantee high reliability of the functions. The BSM uses graphical user interface (GUI) for efficient OAM functions of the BS.

• 정보처리학회논문지:소프트웨어 및 데이터공학
• /
• 제2권1호
• /
• pp.71-80
• /
• 2013

최근에 모바일 기기의 확산으로 인하여 모바일 접근성에 대한 많은 논의가 이뤄지고 있다. 모바일 접근성이란 모바일 기기를 사용하여 애플리케이션을 이용하고자 하는 장애인, 고령자 등을 포함한 모든 사람들에게 모바일 기기의 활용 가능성이 제공됨을 말한다. 본 논문에서는 음성 서비스 기술을 이용하여 모바일 접근성을 향상하기 위한 인터페이스를 제안하고 구현하였다. 제안된 방법은 안드로이드 스마트폰에서 구현하였으며, 시스템에서 제공하는 음성 인식과 음성 합성 기술을 이용하였다. 또한, 전맹인과 저시력자들의 인터넷 접근을 도와주기 위하여 접근성을 고려한 웹 리더 기능을 응용 프로그램 차원에서 설계하고 구현하였다.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
• /
• 제3권1호
• /
• pp.7-14
• /
• 2014

스마트 폰, 스마트 패드 등 다양한 모바일 기기의 등장으로 언제, 어디서나 이동 중에도 끊김없는 멀티미디어 서비스의 필요성이 증대하고 있다. 현재 4G 모바일 기기들은 4G (LTE)와 WLAN (WiFi) 인터페이스를 동시에 가지고 있으며, 이동 통신사업자들은 커버리지가 넓은 4G망 뿐만 아니라 WiFi zone을 통하여 무선 인터넷 서비스를 지원하고 있다. 일반적으로 사용자들은 WLAN 커버리지내에서는 LTE를 통한 서비스 보다도 데이터 사용량에 제한이 없는 WLAN을 통한 서비스를 선호하고 있다. 그러나 WLAN은 L2 핸드오버 지연이 매우 크기 때문에 핸드오버를 수행하는 동안에 끊김없는 서비스가 어려운 문제가 있다. 본 논문에서는 flow mobility를 기반으로 WLAN 간에 핸드오버를 수행하는 동안 서비스 반경이 넓은 4G망을 활용하여 끊김없는 서비스를 지원할 수 있는 방안을 제안하였으며, 테스트베드 구현을 통하여 제안 방안의 우수성을 검증하였다.

• 한국정보통신학회논문지
• /
• 제9권7호
• /
• pp.1524-1528
• /
• 2005

In this paper, we analyses of a traffic for authentication signaling in third generation mobile sensor network. In universal mobile telecommunication system, authentication functions are utilized to identify and authentication a mobile station and validate the service request network services. The authenticating parties are the authentication the serving general packet radio service support node access the authentication center to obtain the authentication with the mobile station. In this paper, we propose that the automatic cost-effective solution size of the authentication vector array.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2005년도 추계종합학술대회
• /
• pp.275-279
• /
• 2005

In this paper, we analyses of a traffic for authentication signaling in third generation mobile sensor network. In universal mobile telecommunication system, authentication functions are utilized to identify and authentication a mobile station and validate the service request network services. The authenticating parties are the authentication the serving general packet radio service support node access the authentication center to obtain the authentication with the mobile station. In this paper, we propose that the automatic cost-effective solution size of the authentication vector array.

• 스마트미디어저널
• /
• 제4권4호
• /
• pp.47-55
• /
• 2015

최근 ICT 분야의 컴퓨팅 패러다임의 변화와 다양한 서비스를 지원하기 위한 VoIP 기술이 재조명 받고 있다. 본 논문에서는 Secured mobile VoIP 기반의 음성 서비스를 지원하기 위한 경량 가상화 기술인 Docker를 이용하여 소프트웨어 PBX인 오픈소스 Asterisk와 하드웨어 플랫폼, 그리고 모바일 단말기간의 시스템들을 설계 및 구현하였다. 그리고 이를 기반으로 네트워크 트래픽의 지연 테스트와 음성 보안 테스트를 글로벌 실환경에서 실증 테스트를 통해 검증하였다.

• Journal of Computing Science and Engineering
• /
• 제5권4호
• /
• pp.316-323
• /
• 2011

Recently, Proxy Mobile IPv6 (PMIPv6) has received much attention as a mobility management protocol in next-generation all-IP mobile networks. While the current research related to PMIPv6 mainly focuses on providing efficient handovers for unicast-based applications, there has been relatively little interest in supporting multicast services with PMIPv6. To provide support for multicast services with PMIPv6, there are two alternative approaches called Mobile Access Gateway (MAG)-based subscription and Local Mobility Anchor (LMA)-based subscription. However, MAG-based subscription causes a large overhead for multicast joining and LMA-based subscription provides non-optimal multicast routing paths. The two approaches may also cause a high packet loss rate. In this paper, we propose an efficient PMIPv6-based multicast protocol that aims to provide an optimal delivery path for multicast data and to reduce handover delay and packet loss rate. Through simulation studies, we found that the proposed protocol outperforms existing multicast solutions for PMIPv6 in terms of end-to-end delay, service disruption period, and the number of lost packets during handovers.

• 한국통신학회논문지
• /
• 제23권9A호
• /
• pp.2230-2239
• /
• 1998

Recently, mobility support of connectionless mobile ATM data service has been mainly studied in wireless ATM communication network. this paper shows the network model for the mobility support of connectionless data service in ATM network, and proposes the methods to minimize COIP (care of IP address) acquisition processing time for MH(mobile host)migration. Th echaracteristics of proposed methods, COIP acquisition probability and IP data communication sequence of proposed model, are discussed in this paper.

• 한국IT서비스학회지
• /
• 제13권2호
• /
• pp.83-97
• /
• 2014

With NFC technology, visitors can easily enjoy exhibit-related information and services. The participating firms can accumulate the visitor data and build up networks with potential visitors. This paper is to report an implementation and operation case of an NFC-based exhibition support service which creates new value as above. For this objective, we introduce the issues in constructing NFC-based exhibition support service. Moreover, we analyze visitor behaviors based on the tag touch data collected, and calculate the economic values generated. The NFC-based exhibition support service in this paper was applied to Hyundai Motors' booth in the 2013 Seoul Motor Show. This paper concludes with implications for business operators that are interested in applying NFC technology to exhibition spaces.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
• /
• pp.143-146
• /
• 2004

Differentiated services (DiffServ) has been widely accepted as the service model to adopt for providing quality-of­service (QoS) over the next-generation IP networks. There is a growing need to support QoS in mobile ad hoc networks. Supporting DiffServ in mobile ad hoc networks, however, is very difficult because of the dynamic nature of mobile ad hoc networks, which causes network congestion. The network congestion induces long transfer packet delay and low throughput which make it very difficult to support QoS in mobile ad hoc networks. We propose DiffServ module to support differentiated service in mobile ad hoc networks through congestion control. Our DiffServ module uses the periodical rate control for real time traffic and also uses the best effort bandwidth concession when network congestion occurs. Network congestion is detected by measuring the packet transfer delay or bandwidth threshold of real time traffic. We evaluate our mechanism via a simulation study. Simulation results show our mechanism may offer a low and stable delay and a stable throughput for real time traffic in mobile ad hoc networks.