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Osnovna svojstva telefonske mreţe, koja opisuju njen kvalitet, su kvalitet prenetog govornog signala i kvalitet u uspostavljanju telefonske veze. Na kvalitet uspostavljanja veze utiĉu mogućnost i brzina uspostavljanja veze. Brzina uspostavljanja veze se izraţava vremenima za koje se obave odreĊene aktivnosti u pojedinim fazama uspo-stavljanja veze. Trajanje ovih faza je propisano normama, koje su odreĊene meĊunarodnim propisima i date su u publikovanim preporukama. Osnovni ĉinilac brzine uspo-stavljanja veze je vreme odziva pozvane strane. Ovaj parametar se definiše kao vremenski interval od slanja poslednjeg adresnog parametra traţenog korisnika od strane pozivajućeg korisnika, do poĉetka odgovora mreţe. U disertaciji je izvršena analiza vremena odziva pozvane strane u telefonskim mreţama i njegovih svojstava. Usled razlika u prenošenju adresnih informacija u klasiĉnim i savremenim paketskim mreţama, uslovi koji se odnose na vreme odgovora pozvane strane nisu isti. Ovaj zakljuĉak je formulisan u predlogu za izmenu postojećih normi koje se odnose na savremene mreţe. U nastavku je opisana mogućnost korišćenja vremena odziva pozvane strane u mešovitoj mreţi kao što je elektroprivredna telefonska mreţa, u cilju donošenja zakljuĉka o radu mreţe. U takvoj mešovitoj mreţi, razliĉite signalizacije i razliĉito trajanje vremena odziva pozvane strane mogu se iskoristiti za nadgledanje ispravnosti pojedinih delova mreţe odnosno detekciju neispravnih veza u njoj. Koristeći ovu osobinu, predloţen je detektor predalarmnog stanja tj. neispravnih veza u mešovitoj telefonskoj mreţi Elektroprivrede Srbije., Main features of telephone network which describe its service quality are the quality of speech signal and the quality of connection setup. The quality of connection setup is affected by the ability and the speed of connection setup. The speed of connection setup is expressed by the time needed for executing of some connection setup phases. Duration of these phases is prescribed by recommended target values, determined in international recommendations. The key indicator of connection set-up speed is post selection delay. This parameter is defined as the time interval from the moment when the complete address information about the called subscriber is sent from the calling subscriber to the network, till the moment when the answer is received from the network. The analysis of post selection delay in telephone networks and its characteristics is performed in the dissertation. Due to differences in transmission of adress information in classic and modern telephone networks, conditions dealing with the post selection delay are not same. This conclusion is formulated in the proposition for changing existing target values related to modern packet networks. In addition, the possibility of using post selection delay in mixed network, such as the telephone network of electric power utility, for monitoring the network operation is described. In such mixed network, different signaling systems i.e. different durations of post selection delay can be used for checking of proper operation of the network parts and detection of faulty connections. Applying this feature, the pre-alarm state detector is proposed.

In this paper we present the telephone network and the recommendations, dealing with the greatest target values of Post Selection Delay. It is shown that the Post Selection Delay is the sum of the delays between the network nodes and that it has the smaller dispersion than the one, recommended as the greatest in the recommendations.

In this paper we present the telephone network and the recommendations, dealing with the greatest target values of Post Selection Delay. It is shown that the Post Selection Delay is the sum of the delays between the network nodes and that it has the smaller dispersion than the one, recommended as the greatest in the recommendations.

In this paper we present the telephone network and the recommendations, dealing with the greatest target values of Post Selection Delay. It is shown that the Post Selection Delay is the sum of the delays between the network nodes and that it has the smaller dispersion than the one, recommended as the greatest in the recommendations.

Bakalářská práce se zabývá problematikou týkající se změn přenášených informací v různých typech sítí. Konkrétně se zabývá změnami analogového a digitálního signálu a vlivy, které tyto změny způsobují. Dále se bakalářská práce věnuje používaným vedením při přenosu těchto signálů a jejich přenosovým vlastnostem. Úkolem práce je nejprve provést teoretický rozbor této problematiky a poté nabyté poznatky aplikovat na konkrétní přenosy signálů ve vybraných typech sítí. Jako součást práce bylo provedeno i měření, které spočívalo v simulaci průběhů různě deformovaných signálů., Bachelor’s thesis deals with issues related with changes of carried information in different types of network. Specifically it deals with changes of analog and digital signal and with influences, which are causing these changes. This thesis deals with used signal leadings too and with their transmission characteristics. The goal of this thesis is to accomplish a theoretical analysis of these issues at first and then to apply acquired knowledges at concrete transmissions at chosen types of networks. There was made a measurement as a part of this thesis too. This measurement consisted in simulation of courses of variously deformed signals., Import 29/09/2010