Abstract: IEEE 802.16 (WiMAX) aims to present high speed
wireless access to cover wide range coverage. The base station (BS)
and the subscriber station (SS) are the main parts of WiMAX.
WiMAX uses either Point-to-Multipoint (PMP) or mesh topologies.
In the PMP mode, the SSs connect to the BS to gain access to the
network. However, in the mesh mode, the SSs connect to each other
to gain access to the BS.
The main components of QoS management in the 802.16 standard
are the admission control, buffer management and packet scheduling.
In this paper, we use QualNet 5.0.2 to study the performance of
different scheduling schemes, such as WFQ, SCFQ, RR and SP when
the numbers of SSs increase. We find that when the number of SSs
increases, the average jitter and average end-to-end delay is increased
and the throughput is reduced.
Abstract: The existing information system (IS) developments
methods are not met the requirements to resolve the security related
IS problems and they fail to provide a successful integration of
security and systems engineering during all development process
stages. Hence, the security should be considered during the whole
software development process and identified with the requirements
specification. This paper aims to propose an integrated security and
IS engineering approach in all software development process stages
by using i* language. This proposed framework categorizes into three
separate parts: modelling business environment part, modelling
information technology system part and modelling IS security part.
The results show that considering security IS goals in the whole
system development process can have a positive influence on system
implementation and better meet business expectations.