Volume1, Number4, 2000


 

 

Title:

A System Model for Mobile and Wireless Networking

Author:

N. Pissinou, M. Hossain and K. Makki

Abstract:

In providing mobile/wireless users with information services to their satisfaction, the supporting software in both Mobile Support Station (MSS) and Mobile Unite (MU) should be designed in such a way that ensures minimum involvement between a mobile user and the MSS without degrading service quality. Applications designed for mobile clients must take into account various network conditions such as available bandwidth, computing resources such as battery power, memory and CPU capability. Some common framework can be designed to take care of all these constraints and relieve the individual applications of this burden. In this paper, we propose a system model that takes care of network conditions, caches data in persistent storage on users’ behalf and processes users’ requests, all in one user-support-application.

 

 

Title:

Traffic Shaping for QoS Control in MPEG Video Transmission over Integrated Services

Author:

M. F. Alam, M. Atiquzzaman and M. A. Karim

Abstract:

The Internet Engineering Task Force (IETF) has proposed the Integrated Services model for providing Quality of Service (QoS) guarantees to real-time applications like variable-bit-rate video and multimedia. Before starting a session over the Integrated Services, resources need to be reserved from the network for supporting the data flow. The resource reservation process depends on the characteristics of the traffic to be generated by the end application as well as the level of QoS guarantee required by the end application from the network. Once a flow is set up, it is required that there is a traffic shaping mechanism so that the traffic generated by the application conforms to the prenegotiated traffic specification. Although the token bucket (with leaky bucket peak rate control) algorithm can be used for traffic shaping in the Integrated Services, a simpler approach for traffic shaping is desired for increased efficiency. We propose a simple and efficient traffic shaper that is much easier to implement than a token bucket traffic shaper, and works coherently with token bucket traffic policing elements in an Integrated Services network. We develop an analytical model of the proposed shaper and carry out numerical simulation of the shaper performance using MPEG trace data from several different movie clips. The numerical simulation results are in excellent agreement with the analytical model. For different types of MPEG video sequences, effects of the proposed traffic shaper parameters on delay and buffer requirement are studied. Our study also provides a straightforward method of determining the traffic specification (TSpec) parameters that have to be specified while setting up a flow in an Integrated Services network from QoS parameters.

 

 

Title:

On Mobile Internet Telephony: Mobility Support of Signal Initiation Protocol (SIP)

Author:

Melody Moh, Gregorie Berquin and Yanjun Chen

Abstract:

The Internet has recently become the most important, popular way of communication. A significant new feature of Internet is the support of telephony. Two main competing signaling protocol standards have been developed for this purpose: H.323, proposed by the ITU, and SIP (Signal Initiation Protocol), proposed by the IETF. Another new feature for the Internet is the support of terminal mobility. The IETF efforts in this field have resulted in the Mobile IP standard. Recently, Liao has shown that Mobile IP doesn’t provide fast enough handoffs to support voice communications. Liao has also demonstrated how H.323 may be extended to offer a solution. In this paper we address several major issues for supporting mobility on SIP. We detail the mechanisms for extending SIP to support location management, registration of roaming mobiles, and handoffs. The mechanisms are either simple extensions of existing SIP, or based on Mobile IP, and thus may be readily employed over the Internet. We believe that the work presented here is an important step towards supporting mobile telephony over the Internet.

 

 

Title:

PIONets: Polyhedral Interconnection of Optical Networks

Author:

Sam Makki, N. Pissinou and Ashwin Gumaste

Abstract:

Multihop lightwave networks[1] form the backbone of most metropolitan area networks employing WDM. Shufflenet[2], De bruijn graph and TIONets[3] are examples of such multihop networks. We put forth another multihop network intended for metropolitan area networks using packet switching and store and forward schemes for routing. This new structure named PIONet or Polyhedral interconnection of Optical Networks is a unique case study for issues of scalability and fault tolerance. In this paper we also examine the ability of this network to grow as well as the high degree of fault tolerance it possess.

 

 

Title:

TCP over IEEE 1394 Home Networks

Author:

Chiewon Lee, Jongwook Jang and E.K. Park

Abstract:

TCP typically offers reasonable end-to-end performance to users regardless of the bandwidth and error characteristics of particular network technology. The robustness of TCP has contributed to its success in the internet environment. The role of communications is already well established in the office environment. With the advent of cheap, affordable broadband communications and the increasing complexity of consumer goods, it seems natural to extend the network into homes. In-home networking means a high-speed communication among the digital appliances within a home. Introduction of application over high-speed home network using TCP/IP protocol is increasing. The integrated environment of internet and home network is demanding as well. We have validated TCP model over high-speed home network environment, investigated the throughput behavior of TCP over IEEE 1394 home networks, and evaluated a potential solution for high performance of TCP over IEEE 1394 home networks. The simulation model has produced several interesting results in the performance of TCP over IEEE 1394 home network.

 

 

Title:

The Self-Correction Method For Programming Language Tutoring System

Author:

Nammee Moon

Abstract:

In this study, We suggest an effective program self-correction method which can be applied to variety of languages. Rather then a number of plans lists in static analysis, a certain program frame is used for planning. That is, a standard program frame given by inputs creates some rules that can recognize novice’s programs. The static analysis is executed by a comparison between a expert program and a student program. The dynamic analysis that suggested in this research has limited analysis coverage in order to draw a solution for the data storage problem. That is, we suggest the method to solve the problem the information derived from the static analysis and by narrowing down analysis boundary. The analysis of the outputs by the dynamic approach is made by using the temporal vector that has recorded the match information of the symbol and timely movement of the variable. This paper presents a design and implementation of PROgramming Language Tutoring System which is named as PROLTUS.