Performance modeling of the contention-based reservation protocol in GPRS/EGPRS under bursty traffic is practically useful in system design. Instead of using discrete event simulation, in this paper we construct an analytical model based on stochastic Petri net formalism to efficiently investigate GPRS uplink performance. The model is built to capture the major features of a realistic system, t...

The General Packet Radio Service (GPRS) is a new bearer service for GSM that greatly simplify wireless access to packet data networks, e.g., to the Internet, to the corporate LAN or to the mobile portals. It applies a packet radio standard to transfer user data packets in a well-organized way between Mobile Stations (MS) and external packet data networks. The introduction of guaranteed performa...

With its great features like providing access to users at anytime and anywhere in the world, mobile communication has been very attractive among the users as well as operators and service providers. However, despite of several advantages, mobile communication has also been facing many security problems. In 2G and 3G technologies like GSM, GPRS and UMTS, the architectures comprise of mainly thre...

The project mainly aims in design and implementation of Base board and the internet communication system based on GPRS. For such an environment, such as radiation, pollution, dangerous, distributed environment where the staff is not easy to reach, it is difficult to complete data collection and realtime monitoring through the traditional manual method. The study of remote wireless monitoring sy...

Hospitals rely on pagers and ordinary telephones to reach staff members in emergency situations. New telecommunication technologies such as General Packet Radio Service (GPRS), the third generation mobile phone system Universal Mobile Telecommunications System (UMTS), and Wireless Local Area Network (WLAN) might be able to replace hospital pagers if they are electromagnetically compatible with ...

General Packet Radio Service (GPRS) provides mobile users end-to-end packet-switched services by sharing the radio channels with voice and circuit-switched services. In such a system, radio resource allocation for circuit-switched and packet-switched services is an important issue, which may affect the QoS for both services significantly. In this paper, we propose two algorithms: Dynamic Resour...

Push-to-Talk (PTT) is a service that allows users using mobile phones in a way like walkie-talkie. All big telecommunication vendors and operators consider PTT an emerging application. 3GPP and OMA regulate the PTT specifications on the basis of Session Initiation Protocol (SIP) to assure interoperability. However, current PTT services are dedicated to cellular phones. We would like to realize ...

Due to the recent spectrum scarcity challenges, a cognitive radio approach has been proposed to opportunistically reuse the allocated spectrum for efficiency purposes. Different from cognitive radio, which is non-collaborative in general, we propose a spatial spectrum access architecture for reusing the spectrum allocated to standard commercial wireless systems, such as GPRS, in which the secon...

Beyond 3G-environments are typically defined as environments that integrate different wireless and fixed access network technologies. In this paper, we address IP based Mobility Management (MM) in beyond 3G-environments with a focus on wireless access networks, motivated by the current trend of WiFi, GPRS, and UMTS networks. The GPRS and UMTS networks provide countrywide network access, while t...

A dynamic network-based Virtual Private Network (VPN) deployment, which is established between the General Packet Radio Services (GPRS) border gateway and a corporate Intranet gateway, is presented and analyzed. By relying on a sequence of concatenated protection mechanisms (GPRS ciphering and VPN deployment), it is possible to provide secure remote access to mobile users without requiring an e...