The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The IP Multimedia Subsystem (IMS) seems to be the technology that will prevail in Next Generation Networks (NGN s), since the interworking environment and the service flexibility that this technology offers to the currently deployed wireless broadband technologies makes it appealing to users, service developers and network operators. In this paper a heterogeneous network model based on the IMS that...
Increasing demand for ubiquitous high speed data access has resulted in widespread deployment of heterogeneous wireless networking domains. Integration of heterogeneous networks presents some considerable challenges which include the demand for seamless handoff, continuity of data traffic & multimedia sessions and central authentication system, billing & security. In this paper the...
Nowadays users have a multitude of ways to connect with other users or applications servers to send and receive data. One of the most used is WIFI and UMTS (3G) networks. These technologies must satisfy users' requirements especially those related to real time applications such as IP telephony or video streaming. Therefore WIFI and UMTS must implement QoS techniques to reach this satisfaction. Both...
Next Generation Wireless Networks (NGWNs) are expected to provide high data rate and optimized quality of service to multimedia and real-time applications over the Internet Protocol (IP) networks. To achieve these goals, handover plays a very critical role in maintaining the seamless connectivity when mobile terminals move across different cells or networks. In this paper, we propose a novel scheme...
During a UMTS (Universal Mobile Telecommunication System) call setup, one part of the signaling messages is sent on a DL (Downlink) 13.6 kbps and UL (Uplink) 13.6 kbps and another part is sent on DL3.4/UL3.4 kbps. The change of the signaling rate from 13.6 kbps to 3.4 kbps occurs after the RRC (Radio Resource Control) Radio Bearer Setup message. In this paper a new method, called ‘Delay of Activation...
Next Generation Wireless Networks (NGWNs) focus on convergence of different Radio Access Technologies (RATs) providing good Quality of Service (QoS) for applications such as Voice over IP traffic (VoIP) and video streaming. The voice applications over IP networks are growing rapidly due to their increasing popularity and cost. To meet the demand of providing high-quality of VoIP at anytime and from...
Fast and secure availability and retrieval of mission critical information for mobile emergency units over a public communication infrastructure is a key factor that determines the mission success during emergency situations. However, the uninterrupted and secure access to public authority databases by the emergency managers, while they are moving towards the scene of incidence in a highly heterogeneous...
Today's laptops and mobile terminals are equipped with several network interfaces belonging to different access technologies. Users can benefit from multi-homing to access network services anywhere, at any time and from any network. Multipath TCP (MPTCP) is a modified version of Transmission Control Protocol (TCP) which allows a TCP connection to simultaneously send data over multiple paths. One of...
This paper presents the results of the performance evaluation concerning 3G/3GPP IP Multimedia Subsystem (IMS) applications deployed in a wireless multi-hop network controlled by the Delay-Aware Network Utility Maximization System (DANUMS). The main purpose of the DANUM system is simultaneous service of files and multimedia streams, i.e., types of traffic of different delay requirements. DANUMS combines...
OWD is becoming increasingly important nowadays, as SLA agreements use it as a parameter to ensure QoS levels. However, its measurement is still a much debated topic due to the difficulty in the clock synchronization process. The paper approaches a new methodology to measure OWD, using NTP protocol with virtual clocks and bigger packets. This approach works over a measurement tool developed by the...
More and more mobile terminals are embedded with multiple heterogeneous interfaces. Multi-interface mobile terminal can benefit from connecting simultaneously to more than one network. Handling mobility at the transport layer can support seamless handover in the context of heterogeneous networks. In this paper, multihoming and end-to-end features are analyzed to present the proposal of Multihoming-based...
3G/UMTS-WLAN heterogeneous mobile network is a complementary platform for the trend of Beyond-3G (B3G) wireless data communications. However, the design of a securing authentication protocol in 3G/UMTS-WLAN heterogeneous mobile networks is a challenging task. Even though EAP authentication and key agreement protocol (EAP-AKA) is adopted by 3rd generation partnership protocol (3GPP) to achieve authentication...
In 3G cellular networks, the release of radio resources is controlled by inactivity timers. However, the timeout value itself, also known as the tail time, can last up to 15 seconds due to the necessity of trading off resource utilization efficiency for low management overhead and good stability, thus wasting considerable amount of radio resources and battery energy at user handsets. In this paper,...
The high end-user data rates provided by HSDPA makes it a realistic alternative of wired Internet access. New 3GPP releases and the migration to packet based transport are further improving the capabilities of HSDPA. As a result, mobile data traffic is continuously increasing, various packet based services and applications with different QoS requirements are now accessible through HSDPA systems. This...
We focus on the problem of efficient dissemination of available gateways information throughout a Vehicular Ad-hoc Network (VANET). Contrary to previous works, we also consider how the gateway discovery protocol affects user data flows that are routed to the infrastructure network. The cases of both delay-tolerant and delay-constrained user traffic are studied. We propose two schemes targeted at reliable,...
This paper presents an innovative solution for the deployment and management of vehicular services based on IP Multimedia Subsystem (IMS). We justify our proposal by analysing the advantages of IMS applied in vehicular scenarios. For this purpose we have designed and experimentally developed a platform that consists of an IMS Core, advanced enablers and two IMS Clients. We demonstrate the potential...
The success and efficiency of managing an emergency situation (such as rescue operation, fire fighting etc.) depends on enabling a system that would ensure the timely availability of high-quality and latest information to the emergency Mobile Units (MU). The system must ensure the provisioning of relevant information in a secure manner irrespective of the location and/or mobility of the MU. The enabling...
Seamless mobility across heterogeneous wireless networks requires a certain level of Quality of Service (QoS) to be assured as it determines the packet loss and delay during handoff procedure. Selecting the target network in an appropriate time plays a crucial role towards achieving ubiquitous networks. This paper proposes a network discovery and selection method called Improved Access Router Discovery...
Targeting the distribution of accurate frequency and time references across Packet Switched Networks (PSNs), the IEEE Std 1588™-2008 (a.k.a. 1588V2 or PTPV2) standard specifies network infrastructure components intended to reduce the impact of network elements located between the Grandmaster clock and Slave clocks. Also referred to as On-Path Supports (OPS), these PTPV2 build-in network components...
IMS is the new approach adopted by 3GPP towards networks convergence. It was designed to be access independent and ubiquitous. IMS already provides personal mobility for nomadic users, but still needs to deal with service continuity within non 3GPP networks. In this paper we propose a novel hybrid mobility management scheme, based on tight cooperation between fast handovers for mobile IPv6 (FMIPv6)...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.