We extend an existing model proposed for estimating project duration for industrial projects in general, to software intensive systems projects. We show, through nine different cases studies from different sectors, that product similarity, measured in terms of requirements reuse, can be incorporated into that model to improve its applicability in software intensive systems projects.

With the increase in demand for higher-quality and more capable IT services, IT organizations in order to obtain competitive advantage require extensive knowledge that needs to be shared and reused among different entities within the organization. The existing IT Service Management (ITSM) mechanisms mention the importance of organizational learning (OL) and knowledge management (KM) for IT organizations. However, they do not explicitly address how OL capabilities of an IT organization can be assessed. This paper, by using an OL assessment model developed for software organizations, namely AiOLoS, shows that with the proper adjustment, the application of the model to IT organizations is feasible. We report the results of applying the model in four functional teams in an IT organization from private sector.

In this paper we investigate the performance of Internet group management protocol version 3 (IGMPv3) and real time transport protocol (RTP) for various scenarios. For this purpose, a network simulator is developed using C++. As it is important to evaluate protocol performances under realistic conditions, the simulation models and network traffic models that are used in the simulations are developed to reflect real life behavior. The simulation models are verified and the performance results obtained are compared with the past studies.

A simulation-based performance evaluation of the wireless application protocol (WAP) transport layer protocol, which may be suitable for combat net radio (CNR), is presented. In the simulations, the wireless transaction protocol (WTP) layer that is the transport layer of WAP is modeled in detail according to WAP forum specifications. Wireless transport layer security (WTLS) layer is excluded in this paper. The user datagram (UDP) protocol is modeled for the bearer adaptation protocol of the transport layer of WAP. The wireless session protocol (WSP) layer is modeled with some basic features. The OPNET model of MIL-STD-188-220B standard is used for the bearer network of WAP. Some user profiles are constructed for the application layer. These profiles are modeled implicitly with source generators and/or explicitly by implementing their process model. These user profiles simulate FTP, HTTP and E-MAIL applications. The protocols are simulated on "OPNET modeler radio". Frequency hopping radios are assumed during the simulations.

An approximation heuristic is proposed for solving the heterogeneous multi-server queueing problem associated with the analysis of resequencing of packets travelling over multiple physical links in a packet-switching network. Even though a method for obtaining the exact solution exists, its processing time and memory requirements vary exponentially in terms of the number of servers and render it infeasible even for moderately-sized systems. Precision of the proposed approximation which has linear time complexity is demonstrated. The approximation is recommendable in cases when system population and resequencing delays, rather than individual link utilizations, have to be calculated.>

This paper proposes a highly parallelized architecture for a distributed queue dual bus (DQDB) MAC layer protocol processor, that is expected to improve the speed of execution of the protocol significantly to match the gigabit per second transmission rates. The architecture is based on pipelines of service blocks operating in parallel. Also the receive and transmit functions are separated and parallelized. Thus, basically, the isochronous, connection-oriented and MAC services are defined as three parallel blocks, each consisting of parallel receive and send functions. Fundamental to the architecture are multiport global receive and send memories which allow manipulation of separate data units in parallel without having to physically transfer data between different service stages. Each service block is divided into parallel subblocks, thereby exploiting the possibility of parallelism and pipelining as much as possible.>