• Journal of Korea Multimedia Society
• /
• v.4 no.4
• /
• pp.339-348
• /
• 2001

In this paper, a cell scheduling algorithm which can be applied to all of the service class in ATM network is proposed. The proposed algorithm classifies the order of priority in each service class into 4 categories and generates the weight of each class service based on the traffic parameters which are negotiated in connection contract. The proposed algorithm guarantees QoS(Quality of Service) to the traffic which is sensitive to delay carrying out CBR and rt_VBR service. As it effectively manages the connection which has small bandwidth, it minimizes the cell delay in the queue. For verifying the effectiveness of the proposed algorithm the proposed algorithm is simulated with existing cell scheduling algorithm and the result is showed.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2002.04b
• /
• pp.1393-1396
• /
• 2002

무선 ATM(Asynchronous Transfer Mode) 망을 기본으로 하여 ATM망에서 사용하는 서비스 종류인 CBR(Constant Bit Rate), rtVBR(Real-Time Variable Bit Rate), nrtVBR(Non-Real-Time Variable Bit Rate), ABR(Available Bit Rate), UBR(Unspecified Bit Rate)에 따른 플로우를 우선 각 서비스 흐름에 따라서 공평하게 패킷 스케줄링 한다. 그리고 각 서비스 종류에 따라 대역이나 지연에 따라 모든 사용자의 다양한 서비스 트래픽에 공평하게 서비스하는 구조를 갖는다. 아울러 무선 통신망 채널에 에러가 발생할 경우를 고려하여 각 서비스 트래픽에 대한 QoS(Quality of Service)를 보장해주는 무선 ATM 통신망에서 동작하는 스케줄링 알고리즘을 제안하여 시뮬레이션과을 통해 기존의 방법과 성능을 비교하여 기존의 유선 통신망 스케줄링 알고리즘과 달리 무선망의 에러에 대한 각 트래픽의 에러에 대한 성능 향상에 대해 알아본다.

• Journal of the Korea Computer Industry Society
• /
• v.3 no.1
• /
• pp.19-26
• /
• 2002

This paper propose the queue structure of cell buffering in the output buffer of ATM switch for the traffic with the different QoS. The proposed queue structure can minimize the cell loss ratio of bursty traffic, maximize the queue utilization through the sharing of real-time queue and non-real-time queue. To evaluate the proposed queue structure, we compare the CLP and cell average delay of the proposed queue and fixed queue using the bursty traffic patterns.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.42 no.2 s.332
• /
• pp.89-96
• /
• 2005

In this paper, we propose a customer premise platform for processing multimedia data service on the ATM network. The proposed platform has a specific AAL2 processor that includes AAL2 protocol and scheduler algorithm so as to off-load large potion of burden from host processor and make it easy to process multimedia data from the ATM network in real time compared with conventional platform in which AAL/ATM tasks are processed by software. The ATS scheduler that is implemented based on 2-level time slot ring provides a simple and efficient method for scheduling data of VBR-rt, UBR and CBR traffics. TMS320C5402 DSP is used to process voice-related tasks such as voice compression and voice packet manupulation and AAL2 processor is implemented on $0.35\;{\mu}m$ process line. We implemented the customer premise equipment for VoDSL service and tested the proposed platform on a test bed network. The experimental results show that the proposed equipment has the call success rate of $97\%$ at least and provides voice service of toll-qualify.

• The KIPS Transactions:PartC
• /
• v.8C no.6
• /
• pp.805-814
• /
• 2001

In this paper, we propose a new scheduling algorithm that guarantees the delay property of real-time traffic, not considered in previous DWRR(Dynamic Weighted Round Robin) algorithm and also transmits non-real-time traffic efficiently. The proposed scheduling algorithm is a variation of DWRR algorithm to guarantee the delay property of real-time traffic by adding cell transmission method based on delay priority. It also uses the threshold to prevent the cell loss of non-real-time traffic due to cell transmission method based on delay priority. Proposed scheduling algorithm may increase some complexity over conventional DWRR scheme because of cell transmission method based on delay priority. However, the consideration of delay priority can minimize cell delay and require less size of temporary buffer. Also, the results of our performance study shows that the proposed scheduling algorithm has better performance than conventional DWRR scheme due to reliable ABR service and congestion avoidance capacity.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2001.05a
• /
• pp.125-128
• /
• 2001

Earlier efforts on optical access concentrated on the design of PONs for the collection and distribution portion of the access network. PON architecture is very simple but it requires MAC protocol for control of upstream traffic. This paper proposes a MAC protocol for a broadband access network using an ATM Passive Optical Network supporting CBR/rtVBR, nrtVBR, ABR aild UBR traffic. For the proposed MAC scheme, we present grant field format, minislot format, and bandwidth allocation algorithm.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2001.10a
• /
• pp.353-356
• /
• 2001

Earlier efforts on optical access concentrated on the design of PONs for the collection and distribution portion of the access network. PON architecture is very simple but it requires MAC protocol for control of upstream traffic. This paper proposes a MAC protocol for a broadband access network using an ATM Passive Optical Network supporting CBR/rtVBR, nrtVBR, UBR and ABR traffic. For the proposed MAC scheme, we present grant field format, minislot format, and bandwidth allocation algorithm. from the simulation result, we have confirmed that our proposed scheme ran reduce the average tell delay in comparison to that of conventional MAC schemes.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.28 no.1B
• /
• pp.18-26
• /
• 2003

Earlier efforts on optical access concentrated on the design of PONs for the collection and distribution portion of the access network PON architecture is very simple but it requires MAC protocol for control of upstream traffic This paper proposes a Request-Counter MAC protocol for a broadband access network using an ATM Passive Optical Network supporting CBR/rtVBR, nrtVBR, UBR and ABR traffic For the proposed MAC scheme, we present Grant Field format, Minislot format, and bandwidth allocation algorithm From the simulation result, we have confirmed that our proposed scheme can reduce the average cell delay in comparison to that of conventional MAC schemes.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.24 no.8B
• /
• pp.1426-1437
• /
• 1999

The introduction of fast packet switching networks such as the ATM leads to the possibility of video services with constant quality. However, the fixed traffic descriptor(TD), which is defined by ATM Forum and ITU-T, can not simultaneously satisfy network efficiency and video quality. This paper presents fast resource reallocation protocol (FRRP) which can provide an effective compromise between network efficiency and video quality. This protocol reallocates the network resources and then adapts the traffic to the reallocated resources. In the proposed method, a video session is divided into several time-intervals according to its generated traffic and TD is calculated which well characterizes the traffic during the specific subdivided interval. In addition, a system model, where MPEG coding algorithm and network control are unified, is proposal and the performance of the FRRP in terms of cell loss rate(CLR) is evaluated though the simulation using real video traffic(Star Wars). Simulation results show that the FRRP has only 5 ~35% CLR of the fixed TD.