المستودع الرقمي لـقسم الشبكات

Network availability is a key consideration in disaster planning, but it also has critical impacts on everyday life and work. For organizations, network downtime or sluggishness equates to business downtime, at considerable cost to organizations through inefficiency, lost sales, lack of critical data for decisions, and other harmful effects. First hop redundancy protocols (FHRP) are an essential tool for improving the availability of IP networks. In this paper, we evaluate the three particular protocols of FHRPs, namely the Hot Standby Router Protocol (HSRPv6), Virtual Router Redundancy Protocol (VRRPv3), and Gateway Load Balancing (GLBPv6) using GNS3 tools. The First Hop Redundancy Protocols have been implemented, tested, optimized, and compared to one another in terms of CPU Utilization, Traffic flow, packet loss and convergence time. The comparison indicates which protocol is best in which scenario and which is best among the three protocols.
Mahmud Mansour, Mohamed Alamin Alqomati, Mohmed K. Al-said(3-2022)

in wireless networks, mobility is an important issue because Internet connectivity can only be effective if it is available during the movement of a node. To enhance mobility, the IEEE802.16e standard has set procedures to design wireless access systems to operate on the move without any disruption of services. The major difference between mobile WiMAX and fixed WiMAX is mobility support. However, speed and trajectory of nodes are unpredictable and can vary even in identical circumstances. In this paper mobile node trajectory is studied under different codecs schemes in order to evaluate the effect of node movement, towards or away from the base-station, on end to end delay, jitter, mean opinion score and throughput of a VoIP application. The results showed that trajectory inward improves network performance since mobile node gets closer to the base-station and hence signal is improved and less power is required. arabic 12 English 67
I. Almerhag, N. Aboalgasem(5-2017)

Abstract: In WiMAX networks, the biggest challenge is to overcome the effects of fading especially when nodes are mobile. The multipath nature of channel leads to ISI (Inter Symbol Interference) and the severity of ISI effects increases with bandwidth increase and this might get worse when nodes are moving . The radio link between the Base Station and Service Station/Mobile Station can be a LOS or it can be a NLOS. The environmental objects and features like buildings, weather conditions can severely obstruct NLOS signal. In this paper the effect of pedestrian multipath and node mobility in WiMAX network is studied under different codecs schemes in order to evaluate the effect of multipath channel fading when nodes are moving on the QoS parameters end to end delay, jitter, mean opinion score and throughput of a VoIP application. The obtained results showed that multipath fading with mobile nodes has sever effect on throughput and MOS value for all studied codecs and on the other parameters the effect varies depending on the implemented codecs. arabic 14 English 71
N. Aboalgasm, I. Almerhag , A. Daeri(3-2018)

A performance evaluation of sound recognition techniques in recognizing some spoken Arabic words, namely digits from zero to nine, is proposed. One of the main characteristics of all Arabic digits is polysyllabic words except for zero. The performance analysis is based on different features of phonetic isolated Arabic digits. The main aim of this paper is to compare, analyze, and discuss the outcomes of spoken Arabic digits recognition systems based on three recognition features: the Yule-Walker spectrum features, the Walsh spectrum features, and the Mel frequency Cepstral coefficients (MFCC) features. The MFCC based recognition system achieves the best average correct recognition. On the other hand, the Yule-Walker based recognition system achieves the worst average correct recognition. arabic 7 English 60
A. Ganoun, I. Almerhag(6-2012)

Multipath Transmission Control Protocol (MPTCP) has been proposed by the Internet Engineering Task Force (IETF) working group, in order to get benefit of the interfaces in the network devices, as most of these network devices are equipped with more than one interface. MPTCP splits a single data stream across multiple paths. This has obvious benefits for reliability, and it can also lead to more efficient use of network resources. The main aim of this paper is to study the main mechanism of the MPTCP and some of the multipath transmission protocols. arabic 5 English 43
Mariam Abojela Msaad, Taha Arabi , Amer R. Zerek(1-2013)

Virtual Private Network (VPN) technology provides a way of protecting information being transmitted over the Internet, by allowing users to establish a virtual private “tunnel” to securely enter an internal network, accessing resources, data and communications via an insecure network such as the Internet. A VPN is a communications environment in which access is controlled to permit peer connections only within a defined community of interest, and is constructed though some form of partitioning of a common underlying communications medium, where this underlying communications medium provides services to the network on a nonexclusive basis. arabic 6 English 50
Mariam Abojela Msaad, Amer R. Zerek, Hana H. saleh(1-2012)

Multi Protocol Label Switching (MPLS) is a core networking technology that operates essentially in between Layers 2 and 3 of the OSI model; for this reason, MPLS has been referred to as operating at Layer 2.5. MPLS can overlay existing technologies such as Asynchronous Transfer Mode (ATM) or Frame Relay, or it can operate in an entirely IP native environment; this can allow users to take advantage of existing Customer Premises Equipment (CPE) while making a move towards converging all network traffic, such as data, video and voice, at a pace that users can accommodate and afford. MPLS provides. its users a number of advantageous features such as traffic engineering, network convergence, failure protection, and the ability to guarantee Quality of Service (QoS) over IP. arabic 2 English 27
Mariam Abojela Msaad, Amer R. Zerek , Wesam M. Tohamei(1-2012)

LTE’s study phase began in late 2004. The overall goal was to select technology that would keep 3GPP’s Universal Mobile Telecommunications System (UMTS) at the forefront of mobile wireless well into the next decade. Key project objectives were set in the following areas: peak data throughput; spectral efficiency; flexible channel bandwidths; latency; device complexity; and overall system cost. The main decision was whether to pursue the objectives by continuing to evolve the existing W-CDMA air interface (which incorporates HSPA (highspeed packet access) or adopt a new air interface based on OFDM. arabic 5 English 27
Mariam Abojela Msaad, Amer R. Zerek, Fareda A. Elmaryami(1-2014)