Abstracts
from Volume 1, Number 2 of MC2R
GSM Network Signaling
(Tutorial Paper)
Yi-Bing
Lin |
liny@csie.nctu.edu.tw |
Dept. Comp. Sci. & Info. Engr., National Chaio Tung
University, Hsinchu, Taiwan
GSM is a wireless digital signaling network standard
designed by standardization committees from the major
European telecommunications operators and manufacturers.
This article introduces the software platform for GSM
network signaling protocol called Mobile Application
Part (MAP). We describe the MAP services, the MAP protocol
machine, the MAP dialog model, and then illustrate the
MAP specific service primitives by an example.}
Wireless Media Access Control for Highly Mobile
Information Servers: Simulation and Performance Evaluation
Kui
W. Moka |
Alvin
S. Limb |
mok@cs.columbia.edu |
lim@cc.gatech.edu |
aDepartment of Computer Science, Columbia
University, New York, New York USA
bComputer Sciences Department, Clark Atlanta
University, Atlanta, Georgia USA
Innovations of modern digital radio technology has
enabled many large mobile and distributed information
systems, such as inventory tracking systems, to provide
readily accessible voice and data services to end users
despite mobility of data servers. These systems often
contain components that are equipped with radio frequency
identification (RFID) tags and interrogators for wireless
connectivity. However, there are usually large number
of these tagged items in these systems that are highly
mobile. The wireless connections among them are also
prone to failure. In this paper, we evaluate and compare
the performance of two RF tag data access protocols
in a single channel per cell implementation: slotted
ALOHA Time Division Multiple Access (ALOHA/TDMA) and
Direct Sequence Code Division Multiple Access (DS/CDMA).
We use a discrete event simulation model to study
the impact of these protocols on data service under
a diversity of highly mobile operating conditions. Mobile
conditions are captured separately by various levels
of burst error, uplink and downlink disconnections,
and tag population. The results show that performance
of (DS/CDMA) dominates in all mobile conditions. In
the most general cases, (DS/CDMA) outperforms (ALOHA/TDMA)
by 1.5 times faster message time. (DS/CDMA) is particularly
superior in the case of pure uplink disconnections.
For burst error and pure downlink disconnections, (DS/CDMA)
renders as much as 2.0 times and 4.5 times faster message
time respectively.
A Fast Dynamic Channel Assignment Algorithm for
Packet Services in DECT
Antonio
Capone |
Luigi
Musumeci |
capone@elet.polimi.it |
musumeci@elet.polimi.it |
Politecnico di Milano, Dipartimento di Elettronica
e Informazione, Milano, Italy
In this paper we consider the use of DECT access for
packet data services. DECT systems are characterized
by a dynamic channel selection algorithm which allows
to reuse the available radio resources in a flexible
way. The standard channel allocation procedure results
inefficient for packet data applications characterized
by short and frequent messages, which determine fast
varying traffic conditions. We propose an enhanced dynamic
channel selection algorithm, which allows to fulfil
the requirements of packet access in a more efficient
way. The performance characteristics of the new and
standard algorithm have been evaluated by simulation,
and refer both to a scenario for only packet data services
and an integrated scenario for voice and data services.
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