ISDN Research Articles

Design and Implementation of Broadband Services for Small Scale Organization

Abstract: Nodes are building blocks of telecommunication network which are interconnected by telecommunication links for exchanging messages and data. Broadband Integrated Services Digital Network commonly called as Broadband ISDN or BISDN is a high-speed telecommunication network that carry data, voice and video simultaneously over a single channel. It provides interactive services where there is bidirectional flow of information between one or more subscribers and a service provider or distributive services with unidirectional information flow between service provider and subscriber. Speed of B-ISDN normally ranges from 2 Mbps to 1 Gbps and transmission very much relates to Asynchronous Transfer Mode. To design BISDN services for small scale organization, resource management and organization requirements play an important role. This paper provides a design of network model and implementation of broadband services for a small-scale organization by considering advance technology requirements, the challenges faced during the implementation and total estimation of budget for entire implementation.

Evaluation of Clustering Techniques to Estimate the Effective Bandwidth of a Markovian Fluid from Traffic Traces

Integrated services digital networks, designed to transport data in real time, are modeled by a multiplexer system, where several data fluids share a single output. At the time of admission of a new connection, in order to maintain the quality of service (QoS), it is important to know the amount of available resources required by the connections sharing the channel. It is therefore important to have models for the sources and techniques that provide accurate estimates of the resources required for each of them. It is assumed that the network sources are modeled using the Generalized Markovian Fluid Model (GMFM) because of its versatility in describing traffic fluctuations. This is a Markovian fluid where the transfer rate is a random variable whose range and probability distribution are determined by the state of the modulating chain. To measure resource allocation, the concept of Effective Bandwidth (EB) is used, since it allows expressing this magnitude as a function of the model parameters, which will be estimated from traffic traces. As the size of the data to describe the behavior of a source is clearly enormous, they are studied using clustering techniques. In this work, different methods, supervised and unsupervised, are presented to estimate the parameters involved in the calculation of the EB. Finally, the performance of the estimators is analyzed by calculating partition comparison indices, corresponding to the dispatch intervals, which are based on the confusion matrix and the notion of mutual information entropy between partitions, on simulated data.

Prenos Q-signalizacije postupkom tunelovanja u automatskoj telefonskoj mreži integrisanih servisa Vojske Srbije

Introduction/purpose: To specify the practical application of ECMA355 and ECMA-336 Standards for Q-SIG tunneling and the implementation of mapping functions via the existing IP (Internet Protocol) network of the Serbian Armed Forces (Intranet SAF), in the Private Automatic Telephone Network SAF (PATN SAF), as the main part of the Private telecommunication-information networks of integrated services SAF (PISN SAF). Methods: Description of the implemented solution and analysis of the software parameters of the established transmission SIP route, with the display of the results obtained in the fight with jitter and echo in the network. Results: With such a solution, it was achieved that participants from the peripheral parts of the PISN SAF, which operate on the principle of transmission and circuit switching by TDM (Time Division Multiplexing), can connect with each other via the newly established central IP network SAF (Core network) which operates on the principle of transmission and switching packets with the SIP (Session Initiation Protocol), without losing the functionality of QSIG from the framework of the digital telecommunication network of integrated services ISDN (Integrated Services Digital Network). Conclusion: The article deals with the modern IP PINX (Private Integrated Services Network Exchange) manufactured by Mitel, type MX-ONE Service Node 6.0, which is implemented at the transit level PATN SAF and which successfully implements the process of tunneling Q-SIG through the IP network and the necessary functions for mapping the transmission of tunneled QSIG messages and mapping voice (and other audio) information to VoIP (Voice over IP) communication media streams through that network. Also, the basic elements for its software preparation during the introduction of a new SIP route, with a capacity of 30 IP trunks in a transmission beam realized with 100 Mb/s-T Ethernet, are given, and the fight with the present jitter and echo in the network is described. Finally, the paper presents the experience-based values of the parameters for reducing the influence of jitter and suppressing echo.

Stationary joint distribution of a discrete-time group-arrival and batch-size-dependent service queue with single and multiple vacation

Discrete-time queueing systems have widespread applications in packet switching networks, internet protocol, Broadband Integrated Services Digital Network (B-ISDN), circuit switched time-division multiple access etc. In this paper, we analyze an infinite-buffer discrete-time group-arrival queue with single and multiple vacation policy where processing/transmission/service times dynamically vary with batch-size under service. The bivariate probability generating function of queue length and server content distribution has been derived first, and from that we extract the joint probabilities in terms of roots of the characteristic equation. We also find the joint distribution at arbitrary and pre-arrival slot. Discrete phase type distribution plays a noteworthy role in order to regulate the high transmission error through a particular channel. In view of this, numerical illustrations include the service time distribution to follow the discrete phase type distribution.

Internet access standards: dissemination of the Integrated Services Digital Network in Spain, 1984-2005

This article aims to narrate the birth and evolution of the Integrated Services Digital Network (ISDN) in Spain with an essentially descriptive methodology, from an interdisciplinary perspective and from varied sources. The study aims to investigate the forms of the transition from a conceptual or engineering phase to the market in a standard of Internet access and, at the same time, in the different patterns of technological innovation and the factors that motivate them. It tries to verify if the own nature of the techniques, the degree of diffusion of the previous technologies, the technological level -digitalization- and the structure of market of the telecommunications — continued existence of the monopoly of the historical operator National Telephone Company of Spain — had a significant impact on the inequality of penetration with respect to other countries. The research authorizes to conclude that a very heterogeneous combination of factors caused that leading countries in the diffusion of a technology did not achieve that leading role in the diffusion of other technologies.

Cost inspection of a Geo/G/1 retrial model using particle swarm optimization and Genetic algorithm

We have studied a Geo/G/1 retrial model with state-dependent and voluntary services in discrete-time frame. The concept of Bernoulli vacation is also considered wherein, after the execution of each service, the server may hold back for next unit or it may leave for a vacation of arbitrary duration. Priority and impatient units are also analysed. This system is applicable in digital and communication fields where the data is transferred in packets like broadband integrated services digital network (B-ISDN) and all those areas where time is considered as a discrete random variable. All necessary performance indices are established for the developed model. Stochastic decomposition laws for the system size are also provided. The calculated results are verified by performing numerical examples and a detailed illustration. We have further carried out a comparative analysis to obtain minimum cost using direct search method (DSM), Particle Swarm Optimization (PSO) and Genetic Algorithm (GA) techniques.

Performance analysis of asynchronous priority-based internet router under self-similar traffic input - queueing system with Markovian input and hyper-exponential services

In this paper, queueing behaviour of asynchronous priority-based internet router with self-similar traffic input is analysed. As Markov modulated Poisson process (MMPP) emulates self-similar traffic, it is used as input process of pertinent queueing system. For quality of service (QoS) guarantee in a broadband integrated services digital network (B-ISDN), partial buffer sharing (PBS) mechanism is promising one. Since, network traffic is asynchronous and of variable packet lengths, wavelength division multiplexing (WDM) technology is to be employed, according to which, each output port is modelled as multi server queueing system. The service times (packet lengths) are assumed to follow hyper-exponential (Hk) distribution. For the said reasons, router here is modelled as MMPP/Hk/s/C queueing system employing PBS mechanism. High and low priority packet loss probabilities, and mean lengths of non-critical and critical periods are computed, and presented graphically. This analysis is useful in dimensioning the priority-based asynchronous router with self-similar traffic input.

Performance analysis of asynchronous priority-based internet router under self-similar traffic input - queueing system with Markovian input and hyper-exponential services

In this paper, queueing behaviour of asynchronous priority-based internet router with self-similar traffic input is analysed. As Markov modulated Poisson process (MMPP) emulates self-similar traffic, it is used as input process of pertinent queueing system. For quality of service (QoS) guarantee in a broadband integrated services digital network (B-ISDN), partial buffer sharing (PBS) mechanism is promising one. Since, network traffic is asynchronous and of variable packet lengths, wavelength division multiplexing (WDM) technology is to be employed, according to which, each output port is modelled as multi server queueing system. The service times (packet lengths) are assumed to follow hyper-exponential (Hk) distribution. For the said reasons, router here is modelled as MMPP/Hk/s/C queueing system employing PBS mechanism. High and low priority packet loss probabilities, and mean lengths of non-critical and critical periods are computed, and presented graphically. This analysis is useful in dimensioning the priority-based asynchronous router with self-similar traffic input.

Study the BER Performance Comparison of MIMO Systems Using BPSK Modulation with ZF and MMSE Equalization

In the modern age, wireless communication is very helpful in various mobile antenna communication systems. In mobile communication systems, the transmission of data transfer rates is very high and it plays an important role in several services like video, top-quality audio, and mobile integrated service digital network. During the transmission of data at higher data transmission rates through the mobile radio channels, the channel impulse response can spread over many symbol periods as well as cause inter-symbol interference (ISI). Wireless transmission is suffering from fading and interference effects which may be combated with equalizer. Due to fading and interference, it creates a problem for signal recovery in wireless communication. The main objective of this paper is to analyze the different types of equalizers such as ZF and MMSE for BPSK modulation. The simulation result has been developed by using MATLAB toolbox version 2015a and a multi-tap ISI channel is considered. By analyzing the simulation result it shows that if the number of tap lengths is increasing, BER will decrease in ZF equalizer. And finally shows BER vs SNR comparison of two different types of an equalizer and is able to find out MMSE performance is better than ZF equalizer.

Intensive Patient Monitoring Using LabVIEW

In modern years, numerous telemedicine applications have been effectively implemented over wired communication technologies like POTS (Plain Old Telephone Systems) and ISDN (Integrated Service Digital Network). However, nowadays, modern wireless telecommunication means, such as the GSM (Global System for Mobile communication), GPRS (General Packet Radio Service), the forthcoming UMTS (Universal Mobile Telecommunication Systems) mobile telephony standards, and satellite communications, allow the operation of wireless telemedicine systems, freeing the medical personnel and/or the subject monitored from being bound to fixed locations . To offer a comparably dependable and easy way of monitoring for those people using newly available telecommunication technologies, we have proposed an Intensive Patient Monitoring System with database trailing ability. It will observe the results of simulation and its Hardware implementation can coincide up to its maximum accuracy. The investigational results prove the continuous monitoring of vital signs and be corroborate to be successful as per the required conditions. Intensive Monitoring System for various parameters monitoring with database tracking capability promises to be a powerful aid in monitoring multiple patients concurrently.

Performance analysis of a discrete-time Geo/G/1 retrial queue under <i>J</i>-vacation policy

We have investigated a discrete-time Geo/G/1 retrial queue under J vacation policy and general retrial times, which can be applicable to many digital systems, viz. broadband integrated services digital network (B-ISDN), asynchronous transfer mode (ATM) and circuit-switched time-division multiple access (TDMA) systems. In discrete-time systems, we consider time to be a discrete random variable and measure it in fixed size data units, such as machine cycle time, bits, bytes, packets, etc. The server follows J vacation policy according to which as soon as the retrial orbit becomes empty and no new customer arrives then the server may take at most J number of repeated vacations. The server immediately returns from the vacation if at least one customer arrives in the system. The inter arrival time is assumed to be geometrically distributed whereas retrial time, service time and vacation time are assumed to be generally distributed in the discrete environment. The underlying Markov process is analysed by using generating function method whereby we obtain various performance measures of interest. We provide stochastic decomposition laws for the system size of the developed model.

Performance analysis of a discrete-time Geo/G/1 retrial queue under <i>J</i>-vacation policy

We have investigated a discrete-time Geo/G/1 retrial queue under J vacation policy and general retrial times, which can be applicable to many digital systems, viz. broadband integrated services digital network (B-ISDN), asynchronous transfer mode (ATM) and circuit-switched time-division multiple access (TDMA) systems. In discrete-time systems, we consider time to be a discrete random variable and measure it in fixed size data units, such as machine cycle time, bits, bytes, packets, etc. The server follows J vacation policy according to which as soon as the retrial orbit becomes empty and no new customer arrives then the server may take at most J number of repeated vacations. The server immediately returns from the vacation if at least one customer arrives in the system. The inter arrival time is assumed to be geometrically distributed whereas retrial time, service time and vacation time are assumed to be generally distributed in the discrete environment. The underlying Markov process is analysed by using generating function method whereby we obtain various performance measures of interest. We provide stochastic decomposition laws for the system size of the developed model.

Are You Addicted to Your Smartphone, Social Media, and More?: The New AntiSocial App Could Help

Back in 1998, I remember receiving my first second-generation (2G) mobile assignment at telecommunications vendor Nortel: a bid for Hutchison in Australia, a small alternate operator. At that time, I had already grown accustomed to modeling network traffic on traditional voice networks and was beginning to look at the impact of the Internet on data network dimensioning. In Australia, we were still relying on the public switched telephone network to dial up the Internet from homes, the Integrated Services Digital Network in small-to-medium enterprises, and leased lines for larger corporates and the government. But modeling mobile traffic was a different affair.

Real-Time Programmable DSPs for Video Processing: The Challenges of Their Development

Video signals can be processed by homogeneous multiple digital signal processors (DSPs) using the overlap-save method. The target application of the video signal processor (VSP) was video phones and video conferencing, along with the development of International Telecommunication Union-Telecommunication Standardization Sector (ITU-T) Recommendation H.261, video transmission over ISDN lines on which data rates are multiples of 64 kb/s. A commercial H.261 codec was developed based on the proposed VSP architecture, and the extension to high-definition TV (HDTV) signal processing had also been achieved and demonstrated. This article describes the challenge of real-time programmable VSP development during the 1980s.

Centralized detection of pre-alarm state in telephone network of electric power utility

In this paper we consider the mixed telephone network of electric power utility consisting of IP, ISDN and Power Line Carrier links. Very important demand in the network is high availability. The central detector of IP and ISDN link failure (pre-alarm) is presented. The detector function is based on the prolonged response time of the network in the case of IP and ISDN link failure. We define undesirable events in the detector operation: false pre-alarm and miss detection, and we derive the expressions for their probability calculation. It is indicated that centralization of this detector is merit, which facilitates testing of the whole network from one location.

Performance Analysis of Wavelength Division Multiplexing Asynchronous Internet Router Employing Space Priority Mechanism under Self-Similar Traffic Input—Multi-Server Queueing System with Markovian Input and Erlang-k Services

In this paper, we analyze the queueing behaviour of wavelength division multiplexing (WDM) Internet router employing partial buffer sharing (PBS) mechanism with self-similar traffic input. In view of WDM technology in networking, each output port of the router is modelled as multi-server queueing system. To guarantee the quality of service (QoS) in Broadband integrated services digital network (B-ISDN), PBS mechanism is a promising one. As Markov modulated Poisson process (MMPP) emulates self-similar Internet traffic, we can use MMPP as input process of queueing system to investigate queueing behaviour of the router. In general, as network traffic is asynchronous (unslotted) and of variable packet lengths, service times (packet lengths) are assumed to follow Erlang-k distribution. Since, the said distribution is relatively general compared to deterministic and exponential. Hence, specific output port of the router is modelled as MMPP/Ek/s/C queueing system. The long-term performance measures namely high priority and low priority packet loss probabilities and the short-term performance measures namely mean lengths of critical and non-critical periods against the system parameters and traffic parameters are computed by means of matrix-geometric methods and approximate Markovian model. This kind of analysis is useful in dimensioning the router under self-similar traffic input employing PBS mechanism to provide differentiated services (DiffServ) and QoS guarantee.

Remote videolaryngoscopy skills training for pre-hospital personnel.

Videolaryngoscopy (VL) is a novel technology that can facilitate rapid acquisition of intubation skills with simultaneous teacher and learner visualization of laryngeal structures. Videolaryngoscopy improves laryngeal visualization, and improves intubation success in difficult airway management compared to standard direct laryngoscopy. First responders need enhanced airway management tools to improve intubation success rates in civilian pre-hospital and military battlefield settings. We evaluated feasibility and efficacy of a remote first responder videolaryngoscopy skills training paradigm using distance learning by VTC (256kb ISDN) with synchronous transmission of laryngoscopy images to a remotely located trainer. Airway visualization, intubation success rates, and intubation times documented feasibility and comparability of remote and face-to-face introductory familiarization and intubation training with the Storz-Berci videolaryngoscopy system. User acceptance was good. Remote training paradigms for advanced technology solutions such as videolaryngoscopy can accelerate the diffusion of life-saving new technologies, especially when there is limited access to specialized training. Videolaryngoscopy visualization and difficult airway intubation success rates were better than direct laryngoscopy.

Collaborated surgical works (surgical planning) in virtual space with tactile sensation between Japan and Germany.

Surgeons in Japan and Germany applied tele-virtual surgery and a force feedback device during a hepatectomy simulation. Using this system, surgeons in each country were able to perform various surgical maneuvers upon the same patient. They palpated abdominal skin, made electrical scalpel incisions and widened the incision line by using surgical tools in virtual space. While surgeons performed a virtual operation, the force feedback device conveyed tactile sensations. In each location, the force feedback devices and two graphic workstations of equal capability were employed. As each workstation communicated only event signals through an ISDN (64 Kb) line, it was possible to obtain real time tele-virtual surgery without a large capacity communication infrastructure.

Working vacation policy for a discrete-time GeoX/Geo/1 retrial queue

Due to rapid growth of today’s technology in fast speeding digital networks and industrial organizations, there is a need to develop a model which proves to be useful in handling designing issues of computer and telecommunication systems and many other related digital systems. To accomplish this, we have made an attempt to provide a remedy for modeling some discrete-time (digital) systems of day-to-day life viz. Broadband Integrated Services Digital Network (BISDN), Asynchronous Transfer Mode (ATM) and related computer communication technologies, wherein the models for continuous-time queues fail. This is due to the fact that the discrete-time systems are more appropriate than their continuous-time equivalents to model digital systems. In these systems, time is treated as discrete random variable and is measured in fixed size data units such as machine cycle time, bits, bytes, packets, etc. In this study, we analyze a GeoX/Geo/1 retrial queue wherein the service facility may leave for more economical type of vacation schedule, called as working vacation. The inter-arrival-time, retrial time, service time and working vacation time are assumed to be geometric distributed in discrete environment. We have used matrix geometric method to compute various useful performance measures of interest. Further, we obtain joint optimal values of most sensitive parameters such as vacation returning rate (η) and service rate of the server during working vacation (μV) via direct search method based on heuristic approach. Numerical results are also facilitated to depict the performance of the developed model.

A Cost Analysis of a Remote Home Support Programme for Infants with Major Congenital Heart Disease: Evidence from a Randomized Controlled Trial

A Cost Analysis of a Remote Home Support Programme for Infants with Major Congenital Heart Disease: Evidence from a Randomized Controlled Trial Objective: Paediatric cardiology is a highly centralised subspecialty with patients living often living large distances from the tertiary care centre. A tele homecare programme for infants with major congenital heart disease (CHD) was devised to support patients and families during the stressful and vulnerable period following discharge from hospital. This study aimed to describe the costs and potential savings of a telemedicine home support programme for infants with major congenital heart disease (CHD). Methods: A randomized controlled trial was performed at a UK tertiary paediatric cardiology centre. Infants with major CHD discharged home were randomized to one of three groups: Two intervention groups (Video support and Telephone support) and one control group (standard care). Patients in the two intervention groups received regular, standardised remote consultations. Video support initially provided by ISDN lines and later by a home broadband (IP) connection. The main outcome measure was a comparison of total cost to NHS of participants including cost of study interventions and health service utilisation.