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The 2010 Electronics and Telecommunications Research Seminar Series: 9th Workshop ProceedingsSheriff, Ray E. 14 April 2010 (has links)
Yes / This is the ninth workshop to be organised under the postgraduate programmes in electrical and electronic engineering (EEE). The workshop concludes the Research Seminar Series, which has provided a platform for disseminating the latest research activities in related technologies through its weekly seminars. The EEE courses cover a broad range of technologies and this is reflected in the variety of topics presented during the workshop. In total, forty-four papers have been selected for the proceedings, which have been divided into eight sections. The workshop aims to be as close to a `real¿ event as possible. Hence, authors have responded to a Call for Papers with an abstract, prior to the submission of the final paper. This has been a novel experience for many, if not all of the contributors. As usual, authors have taken up the challenge with enthusiasm, resulting in a collection of papers that reflects today¿s research challenges. / School of Engineering, Design and Technology
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The 2009 Electronics and Telecommunications Research Seminar Series: 8th Workshop ProceedingsSheriff, Ray E. 04 January 2009 (has links)
Yes / This is the eighth workshop to be organised under the postgraduate programmes in electrical and
electronic engineering (EEE). The workshop concludes the Research Seminar Series, which has
provided a platform for disseminating the latest research activities in related technologies through
its weekly seminars.
The EEE courses cover a broad range of technologies and this is reflected in the variety of topics
presented during the workshop. In total, thirty-three papers have been selected for the proceedings,
which have been divided into seven sections.
The workshop aims to be as close to a `real¿ event as possible. Hence, authors have responded to a
Call for Papers with an abstract, prior to the submission of the final paper. This has been a novel
experience for many, if not all of the contributors. Clearly, authors have taken up the challenge
with enthusiasm, resulting in what promises to be an interesting and informative workshop.
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Ανάλυση αλγορίθμου μεταπομπής τύπου Soft σε δίκτυο επικοινωνιών τρίτης γενιάς (3G network)Γκίκας, Γεώργιος 13 October 2013 (has links)
Στα κυψελωτά δίκτυα κινητών επικοινωνιών, η διαρκής κίνηση των κινητών συσκευών δημιουργεί την ανάγκη ύπαρξης μηχανισμών οι οποίοι θα διασφαλίζουν το αδιάλειπτο της επικοινωνίας «εν κινήσει». Αυτό ακριβώς επιτυγχάνεται με την εφαρμογή μηχανισμών μεταπομπής, οι οποίοι, με τρόπο διάφανο προς την κινητή συσκευή, συνδέονται δυναμικά με το καταλληλότερο σημείο εκπομπής τηλεπικοινωνιακού σήματος (Σταθμός Βάσης) που εκπέμπει στην ευρύτερη περιοχή.
Στην παρούσα μελέτη παρουσιάζονται και αναλύονται οι υπάρχουσες κατηγορίες μεταπομπής, ενώ δίνεται ιδιαίτερη έμφαση σε αυτές που είναι εφαρμόσιμες στα δίκτυα τρίτης γενιάς (3G). Μία από τις σημαντικότερες κατηγοριοποιήσεις των τύπων μεταπομπής είναι αυτή σε σκληρού τύπου (hard) και μαλακού τύπου (soft ή softer). Σημαντικό πλεονέκτημα του μαλακού τύπου μεταπομπής είναι η διασφάλιση της ανεξαρτησίας καναλιών (channel diversity) η οποία τελικά οδηγεί σε αλγορίθμους μεταπομπής που καταναλώνουν μικρότερες ποσότητες ενέργειας. Από την άλλη στις μεταπομπές μαλακού τύπου γίνεται χρήση περισσότερων πόρων του δικτύου και υπάρχει μεγαλύτερη πολυπλοκότητα.
Στην παρούσα μελέτη μελετώνται οι τεχνικές οι οποίες χρησιμοποιούνται για να ληφθεί η απόφαση εκτέλεσης μεταπομπής. Βασικές κατηγορίες αλγορίθμων απόφασης μεταπομπής είναι αυτοί που στηρίζονται στη στάθμη της ισχύος του λαμβανόμενου σήματος, αυτοί που στηρίζονται σε fuzzy logic και οι αλγόριθμοι προτεραιότητας. Στο πλαίσιο της παρούσας εργασίας μελετάται και αναλύεται κριτικά η σχετική βιβλιογραφική έρευνα που έχει διενεργηθεί και εξακολουθεί να διεξάγεται σχετικά με την εφαρμογή αλγορίθμων μεταπομπής, με έμφαση στις τεχνικές μεταπομπής που βρίσκουν εφαρμογή σε συστήματα CDMA (Code Division Multiple Access).
Επιπλέον, υλοποιείται και προσομοιάζεται, ένα μοντέλο το οποίο συνδυάζει τεχνικές «Γκρι Προβλέψεων» (Grey Prediction) με κλασσικούς μηχανισμούς μεταπομπής με στόχο τη βελτιστοποίηση του πλήθους των εκτελούμενων μεταπομπών, ελαχιστοποιώντας ταυτόχρονα την πιθανότητα απόρριψης κλήσεων (call blocking probability). Η ταυτόχρονη χρήση και αξιοποίηση και των τριών εργαλείων (Matlab, Simulink και Stateflow) απλοποιεί την υλοποίηση και ταυτόχρονα διευκολύνει την αξιολόγηση των παραγόμενων αποτελεσμάτων. Ο βασικός δείκτης επίδοσης με τον οποίο αξιολογείται ο αλγόριθμος που υλοποιείται, είναι το πλήθος των μεταπομπών που εκτελούνται, ενώ οι εκτελεσθείσες προσομοιώσεις στηρίζονται σε τιμές των παραμέτρων που έχουν προταθεί στο (Saeed Changiz Rezaei, Hossein Khalaj, 2005), συνδυασμένες με διάφορες τιμές Υστέρησης (Hysteresis).
Προκύπτει ότι καθώς αυξάνεται η τιμή της Υστέρησης, ο αριθμός των μεταπομπών που εκτελούνται μειώνεται, όπως άλλωστε αναμενόταν. Τέλος, θα πρέπει να επισημανθεί ότι, η πολύ μεγάλη συχνότητα δειγματοληψιών του εν λόγω μοντέλου σε συνδυασμό με την ομαλότητα κίνησης της κινητής συσκευής και την καλή προβλεπτική ικανότητα του Αλγορίθμου Grey Prediction, οδηγεί στον υπολογισμό μιας πολύ ομαλής ακολουθίας διαδοχικών τιμών ισχύος των λαμβανόμενων σημάτων και τελικά σε ελαχιστοποίηση του αριθμού των μεταπομπών που διενεργούνται. / In cellular mobile networks, the continuous movement of mobile devices creates the need for mechanisms that are necessary to ensure continuity of communication. This is exactly what is achieved by applying handover mechanisms, which connect the mobile device, dynamically and transparently with appropriate emission point (base station) in the region.
In the present work, existing categories of handover, with a particular emphasis on those applicable to third-generation networks (3G), are studied and analyzed. One of the major classifications of handovers is that in hard and soft or softer handovers. An important advantage of soft handover is that it ensures the channel diversity which ultimately leads to handover algorithms that consume less energy. On the other hand, in the case of soft handover more network resources are required and greater complexity of the algorithms makes implementation harder. In this study, we studied the techniques used to decide if a handover should be executed in a mobile communication system. There are three basic categories of handover decision algorithms, i.e. those that are based on the level of the received signal power, the algorithms that are based on fuzzy logic and finally the priority algorithms.
In the present study, we analyze critically the relevant literature on handover algorithms, emphasizing on those that can be applied in CDMA (Code Division Multiple Access) systems. In addition, we implement and simulate a model which combines "Grey Prediction" techniques with classical handover mechanisms to optimize the number of handovers performed while minimizing the call blocking probability. The simultaneous use and exploitation of three tools (Matlab, Simulink and Stateflow) simplifies the implementation and at the same time facilitates evaluation of the results. The key performance indicator used to evaluate algorithm’s performance is the number of handovers performed. Performed simulations are based on values of the parameters proposed in (Saeed Changiz Rezaei, Hossein Khalaj, 2005), combined with various values of Hysteresis.
It is evident when looking at the simulation results, that the number of handovers performed decreases, as hysteresis increases. Finally, it should be noted that the very high sampling frequency of the model, combined with the smoothness of the mobile device motion and the good predictive ability of the Grey Prediction Algorithm, leads to the calculation of a very smooth sequence of consecutive values of the received signals and thus to the minimization of the number of handovers performed.
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Between Daring and Deliberating : 3G as a Sustainability Issue in Swedish Spatial PlanningLarsson, Stefan January 2008 (has links)
The thesis shows how different aspects of sustainable development have been handled or not handled in the third generation infrastructure development in Sweden. The difference between the design of the 3G development – emphazising competition, growth and regional access, based on a strong technological optimism - and the implementation, as the roll out struck the landscape, including the non-handled radiation issue and the legal changes in order to facilitate the roll out, is discussed and analyzed. The roll out formally started in late 2000 as the licence allocation process, the so called beauty contest, was finished. Four operators were to build partly competing systems within three years, each covering 8 860 000 persons, more than 99,98 percent of the populated areas. The Post and Telecommunications Agency can sanction operators not fulfilling licence conditions by a considerable fine. The coverage by the end of the period was between 66 and 74 percent of the promised 8 860 000, with only three remaining operators still participating. Not until 1 December 2006 did the first operator report the required coverage, followed by the two remaining operators by 1 June 2007. The municipal permit handling was blamed for the delay, a reason that “could not have been foreseen”, which helped the operators avoid sanctions from the PTA. The thesis shows that a slow municipal permit process can not explain the lack of coverage in some areas of Sweden. Environmental aspects were not handled at national level but assessed locally in the building permit handling, as well as the regional 12:6 consultations at the County Administrations. This is why the municipal permit process holds many of the keys regarding environmental management and planning. Therefore the permit processes regarding 3G masts has been charted as they developed in time and screened for main issues and conflicts. Public participation can be found in the local context tied to the legal concept of being a concerned party in the permit process, or the 12:6 consultation. In spite of this, the much debated radiation issue is lifted from the participative aspects and legally defined as not relevant. The theoretical basis of the analysis combines spatial planning and sociology of law, applying the sociological concept of norms as entities controlling action on the discussion of two different paradigms of governance derived from planning theory. The thesis project has been a part of a study within the MiSt programme, an interdisciplinary research programme on tools for environmental assessment in strategic decision making funded by the Swedish Environmental Protection Agency. Supervisors: professor Lars Emmelin, School of Planning, Blekinge Institute of Technology Karsten Åström, professor in sociology of law, Lund University / MiSt Report 4
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3G的技術標準及專利聯盟 / 3G Technical Standards and Patent Platform涂旭志, Roger,Tu Unknown Date (has links)
隨著全球3G行動通訊產業的快速發展,行動通訊服務市場正從傳統的單純語音走向與資料傳輸整合的趨勢,並發展出多種不同型態的通訊服務方式與系統設備,其中所牽涉到的3G技術範圍十分廣泛而複雜,其技術標準規格的發展則是由3G的技術標準組織所負責制定。本論文研究針對3G行動通訊產業進行解析,並探討3G行動通訊技術標準組織的運作及功能,並進一步瞭解在3G行動通訊技術標準的制定過程中所衍生出來的關鍵性專利問題,此外也特別針對專利聯盟公司3G Licensing Ltd.的成立與運作做一說明,以進一步瞭解3G產業中專利平台運作的情形,最後並總結對台灣行動通訊產業所可以參考的結論與建議。 / 3G technologies are being deployed to worldwide markets rapidly. The mobile services are converging with voice and data transmission. There are various companies involving in 3G system and terminal business. The relative technologies are complicated and quite broad. The 3G standard organizations are the main bodies responsible for the establishment of 3G technical specifications. This article would describe an overview of 3G industries and 3G standard organizations. It would specify how the 3G standard organizations function and discuss the issues of 3G essential patents. Regarding 3G patent platform, this article would also talk about the history and status of 3G Licensing Ltd. In the last chapter, it would try to summarize the key points as the references for Taiwan mobile industry.
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A gestão das competências organizacionais em empresas da cadeia de valor para provimento de telefonia celular de 3ª geração (3G). / Organizational competencies management in the value chain for providing 3ª genneration celular telephone services (G3).Silva, Sandro Marcio da 04 July 2002 (has links)
A tese teve como objetivo analisar os processos de desenvolvimento e compartilhamento intra-empresarial de competências organizacionais. Foi analisada a relação entre a Telemig Celular e as empresas que com ela compunham, em junho de 2002, a cadeia de valor para provimento de serviços de telefonia celular. O desenvolvimento das competências organizacionais foi analisado à luz da perspectiva de oferta dos serviços de 3G. A Telemig Celular foi analisada por meio de entrevistas e um workshop junto ao corpo gerencial. As demais empresas da cadeia foram abordadas via entrevistas junto às gerências de RH e estratégia. A utilização do modelo de Fransman mostrou que as relações entre as empresas ainda não constituem efetivas parcerias. Os elos mais forte da cadeia indústria de equipamentos, baseada no domínio tecnológico, e operadoras, baseadas no acesso ao usuário final - têm liderado as decisões mais importantes da cadeia. Observou-se que o desenvolvimento das competências organizacionais é mais estruturado na camada 1, em que há claras regras de desenvolvimento e proteção das competências, além de diretrizes e alocação de recursos para a realização de pesquisas. Também os investimentos em RH são existentes e mais conectados com a estratégia organizacional. Nas demais empresas da cadeia encontraram-se áreas de RH reduzidas, quando existentes, e que adotam práticas e políticas de gestão tradicionais. A pesquisa mostrou que falta às empresas e, principalmente, ao RH uma visão integrada de negócios e cadeia de valor, o que tem levado à subordinação das empresas brasileiras e menores às empresas multinacionais e maiores. / This paper aimed to analyze the processes of development and intra-company sharing of organizational competencies. It looked at the relationship between Telemig Celular company and its counterparts making up the value chain in June 2002 for providing cellular telephone services. The organizational competency development was considered in the light of the 3G-service supply perspective. Telemig Celular was analyzed through interviews and a workshop with its managers. The other companies in the chain were approached through interviews with their strategy and HR managements. By using Fransman's model it was shown that the company relationships are not effective partnerships yet. The strongest links in the chain equipment industry relying on their technological supremacy, and carriers relying on end user access have been taking the chain's most important decisions. The development of organizational competencies was observed to be more structured in layer 1, where there are clear development rules and competency protection, as well as guidelines and fund allocation for research. Also, HR investments are present, and they are more connected to organizational strategy. In the rest of the chain companies, the research found small HR areas, if any, adopting traditional management practices and policies. And it showed that companies, mainly their HR, lack an integrated view of business and value chain, which has been leading to the subordination of the Brazilian and smaller companies to the multinational and larger ones.
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臺灣3G手機服務使用者的期待-價值滿足之研究 / A Study on the Expectancy–Value Gratification of 3G Mobile Phone Service Users in Taiwan吉佳媛, KHIL KHA WON Unknown Date (has links)
隨著廣播、電信、網路的匯流與數位科技發展,消費者在手機上隨時隨地接受「到處存在」(ubiquitous)的電視服務時代已來臨。2003年,第三代行動通訊系統(The Third Generation,3G)服務在台灣正式推行,2009年2月底3G用戶數首度超越2G,使得3G用戶數佔全行動電話用戶數的一半以上。台灣的3G市場及3G用戶數正繼續成長,不過,卻出現許多3G用戶未(曾)使用3G服務的現象,值得關注。
因此,本研究以使用者角度出發,以Palmgreen與Rayburn的GS-GO模式為主軸,探討目前3G服務使用者跟曾使用3G服務者、3G服務非使用者的追求滿足(GS)。另外,也探討目前3G服務使用者,與曾使用3G服務者的獲得滿足(GO),以及此兩者的GS與GO差異及相關性;並討論此差異是否動搖使用者原始信念,並對後續行為產生影響。還有,目前3G服務使用者與曾使用3G服務者,其滿意度差異為何。進一步,本論文還以Rogers的「創新傳佈理論」,加以比較目前3G服務使用者、曾使用3G服務者,與3G服務非使用者之間的創行特質為何。
本研究選定《i.Q線上問卷調查網》會員作為研究樣本,進行電子郵件的網路問卷調查。研究結論如下:
一、探討目前3G服務使用者、曾使用3G服務者及3G服務非使用者的GS因素部分,本研究結果獲得:以下的GS因素中,三者皆相同,且依序為便利追求、娛樂追求、資訊追求、個人化、社會性、時髦性,以及價格因素。然而,三者在GS因素中,時髦因素無差異,其餘因素則都有差異。而目前3G服務使用者與曾使用3G服務者的GO因素中,三者亦相同,依序為便利追求、娛樂追求、資訊追求、個人化、社會性、時髦性,以及價格因素。然而,兩者間的GO因素中,資訊追求顯示有差異,其他GO因素則沒有差異。
二、探討目前3G服務使用者與曾使用3G服務者的追求滿足(GS)、獲得滿足(GO)差異,與相關性部分,據本研究推論:滿意程度會影響後續使用3G手機服務與否,然而,不滿意程度不會影響後續使用3G使用服務與否。
三、探討創新特質部分:目前3G服務使用者與曾使用3G服務者的兩者間,其創新性並不影響使用3G服務與否。然而,目前3G服務使用者與3G服務非使用者兩者間的創新性差異,則會影響3G服務的使用。此外,創新性差異與各項GS因素的分析結果皆呈現顯著性,其中,又與GS因素中的時髦性因素產生最高度相關。
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Paramétrage Dynamique et Optimisation Automatique des Réseaux Mobiles 3G et 3G+Nasri, Ridha 23 January 2009 (has links) (PDF)
La télécommunication radio mobile connait actuellement une évolution importante en termes de diversité de technologies et de services fournis à l'utilisateur final. Il apparait que cette diversité complexifie les réseaux cellulaires et les opérations d'optimisation manuelle du paramétrage deviennent de plus en plus compliquées et couteuses. Par conséquent, les couts d'exploitation du réseau augmentent corrélativement pour les operateurs. Il est donc essentiel de simplifier et d'automatiser ces taches, ce qui permettra de réduire les moyens consacrés à l'optimisation manuelle des réseaux. De plus, en optimisant ainsi de manière automatique les réseaux mobiles déployés, il sera possible de retarder les opérations de densification du réseau et l'acquisition de nouveaux sites. Le paramétrage automatique et optimal permettra donc aussi d'étaler voire même de réduire les investissements et les couts de maintenance du réseau. Cette thèse introduit de nouvelles méthodes de paramétrage automatique (auto-tuning) des algorithmes RRM (Radio Resource Management) dans les réseaux mobiles 3G et au delà du 3G. L'auto-tuning est un processus utilisant des outils de contrôle comme les contrôleurs de logique floue et d'apprentissage par renforcement. Il ajuste les paramètres des algorithmes RRM afin d'adapter le réseau aux fluctuations du trafic. Le fonctionnement de l'auto-tuning est basé sur une boucle de régulation optimale pilotée par un contrôleur qui est alimenté par les indicateurs de qualité du réseau. Afin de trouver le paramétrage optimal du réseau, le contrôleur maximise une fonction d'utilité, appelée aussi fonction de renforcement. Quatre cas d'études sont décrits dans cette thèse. Dans un premier temps, l'auto-tuning de l'algorithme d'allocation des ressources radio est présenté. Afin de privilégier les utilisateurs du service temps réel (voix), une bande de garde est réservée pour eux. Cependant dans le cas ou le trafic temps réel est faible, il est important d'exploiter cette ressource pour d'autres services. L'auto-tuning permet donc de faire un compromis optimal de la qualité perçue dans chaque service en adaptant les ressources réservées en fonction du trafic de chaque classe du service. Le second cas est l'optimisation automatique et dynamique des paramètres de l'algorithme du soft handover en UMTS. Pour l'auto-tuning du soft handover, un contrôleur est implémenté logiquement au niveau du RNC et règle automatiquement les seuils de handover en fonction de la charge radio de chaque cellule ainsi que de ses voisines. Cette approche permet d'équilibrer la charge radio entre les cellules et ainsi augmenter implicitement la capacité du réseau. Les simulations montrent que l'adaptation des seuils du soft handover en UMTS augmente la capacité de 30% par rapport au paramétrage fixe. L'approche de l'auto-tuning de la mobilité en UMTS est étendue pour les systèmes LTE (3GPP Long Term Evolution) mais dans ce cas l'auto-tuning est fondé sur une fonction d'auto-tuning préconstruite. L'adaptation des marges de handover en LTE permet de lisser les interférences intercellulaires et ainsi augmenter le débit perçu pour chaque utilisateur du réseau. Finalement, un algorithme de mobilité adaptative entre les deux technologies UMTS et WLAN est proposé. L'algorithme est orchestré par deux seuils, le premier est responsable du handover de l'UMTS vers le WLAN et l'autre du handover dans le sens inverse. L'adaptation de ces deux seuils permet une exploitation optimale et conjointe des ressources disponibles dans les deux technologies. Les résultats de simulation d'un réseau multi-systèmes exposent également un gain important en capacité.
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End-to-End Application Billing in 3G / End-to-End Application Billing in 3GChaudry, Kashif, Karadza, Elma January 2002 (has links)
<p>We have 3G on the doorstep but nothing seems to attract ordinary people to this technology. To attract the mass market the telecom industry must show something beyond high bit rates. They must show how ordinary people can take advantage of this new technology. This is done by showing the possibilities of the new technology and by demonstrating applications that it will handle. The telecom industry must convince the telecom operators to invest in this technology and the only thing that matters to them is how much revenue they can make by adopting the upcoming technology. </p><p>To convince the operators industry must show how the operators can charge for the new types of applications that will be introduced soon. This is the main reason why this Master's Thesis has been conducted. The purpose of this thesis is to provide a demonstration to Ericsson's 3G lab in Katrineholm in the form of an IP application with a billing solution. This thesis describes the migration from 1G to 3G and examines existing and future billing strategies as well. </p><p>The IP application is an application that uses progressive streaming in order to stream multimedia content to a PDA connected to a 3G phone. This application is platform independent because it is placed on leading Web servers, Apache and IIS. </p><p>The billing application consists of a number of steps. The first step is logging, which is performed by the Web server on which the streaming application is placed. The second step, processing and billing, is performed in the BGw, which is Ericsson's mediation tool, and the SQL server.The third step is displaying the bill, which is done by using ASP to create an active HTML page.</p>
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Emulation of IP Core Network for Testing of the Serving GRPS Support Node (SGSN) Routing ApplicationTorkaman, Hossein January 2009 (has links)
<p>This thesis aims to investigate a method and tool for emulation of the General Packet Radio Service (GPRS) core network needed as an environment to test the routing functionality. GPRS is the most widely adopted mobile packet data delivery technology in the world. It utilizes an Intranet Protocol (IP)-based core network and involves significant changes to the way the Global System for Mobile communications (GSM) air interface is structured. It also forms the basis of the future structure of mobile network transmission and switching.</p><p>The Serving GPRS Support Node (SGSN) is the most fundamental node in GPRS. Ericsson produces and manages an increasing number of SGSN nodes in the world. One of main functionalities of SGSN node is to forward IP packets according to the destination address in the IP header on IP core network.</p><p>In each new release of SGSN, or when implementation or upgrades have been done on routing application on SGSN, design and test engineers at Ericsson need to emulate the IP core network. This must be done with use of many routers to generate huge amounts of data that can simulate the real world IP core network.</p><p>The major goal of this thesis was to analyze and verifying the use of a suitable and economical solution to emulating IP Core Network of the GPRS system for testing of different functionality of the routing application running in SGSN , instead of building up a physical Core Network with different infrastructure and many routers.</p><p>The method chosen for emulating the IP core network with many routers, and investigated in the thesis, is based on a Cisco simulator called “Dynamips”, which runs many actual Cisco Internetwork Operating Systems (IOS) with many different models of Cisco products in a virtual environment on Windows or Linux platforms. With this simulator, engineers at Ericsson will be able to use this simulator to emulate IP core network easily and efficiently to accomplish system test cases.</p><p>A conclusion of this work is that Dynamips could be used to emulate many complicated IP core network scenarios, with many routers to generate huge amounts of data to simulate the real world IP core network. The emulated system fulfils its purpose for testing of the routing application of SGSN regarding different functionality and characteristics. This is done to ensure and verify that SGSN routing application meets its functional and technical requirements, and also helps to find undiscovered errors as well as helps to ensure that the individual components of routing application on SGSN are working correctly.</p>
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