This article presents a review of the investigation of the possibility of increasing the efficiency of existing line test solutions for troubleshooting testing for IPTV over xDSL, by the results of experimental research on real system under commercial exploitation. At the beginning of this article the main weaknesses of the existing troubleshooting testing are described. In the continuation of the article the physical layer parameters of xDSL transceiver are listed. In the reset this article provides a few specific examples of xDSL lines with their physical layer parameters of xDSL transceivers followed by analysis how they can be used for the purposes of more efficient measurement of parameters of copper pairs.

This paper presents a simple comparison between line conditions produced by using two types of local loops which operate in VDSL (Very-high-bit-rate speed Digital Subscriber line) environment. The object of observation is copper transmission line that remains in access network after replacing copper wires from CO (Central Office) to DP (Distribution Point) with optical fibres, i.e. after implementing a FTTB (Fibre to the Building/Basement) solution. Two borderline loop types from opposite edges are used: purposefully manufactured DSL indoor cable and ordinary flat telephone indoor cable. The paper gives at first a short overview of previously introduced and verified short loop model in DSL, followed by brief description of its leading testing scenarios. After that, major testing scenarios are implemented on two observed loop types under same conditions. An explanation of obtained results with appropriate discussion is done at the end. Primary loop coefficients and transfer functions are used as observed quantities. All results of measurements and observations are collecting on real system in operation conditions.

This paper shows a review investigation the possibility of increasing the efficiency of existing line test solutions for troubleshooting IPTV over xDSL, by the results of experimental research on real system under commercial exploitation. At the beginning of this paper the main weaknesses of the existing troubleshooting testing are described. In the rest of the paper the parameters of the physical layer of xDSL transceiver are listed, followed by analysis how they can be used for the purposes of more efficient measurement of parameters of copper pairs.

This paper introduces a very simple testing scenario for detecting of faults in copper local loop that remains in access network after replacing copper wires from CO (Central Office) to DP (Distribution Point) with optical fibres, i.e. after implementation of FTTB (Fibre to the Building/Basement) solution. The scenario can be useful at first for quick and quite reliable loop troubleshooting, and in particular cases for loop qualification. The first part of the paper gives a short overview of copper loop model in DSL (Digital Subscriber Line) environment, its lead testing scenarios and FTTB solution. A main steps in fault analysis and testing scenario description follow. Below that, a discussion proposed scenario usability and reliability is provided. At the end an experimental verification of the scenario, which is based on data collecting on physical system in commercial exploitation is done.

This paper introduces a very simple model of copper local loop that remains in access network after replacing copper wires from CO (Central Office) to DP (Distribution Point) with optical fibres, i.e. after implementing a FTTB (Fibre to the Building/Basement) solution. The model can be used for quick and quite reliable loop qualification and/or troubleshooting. The first part of the paper gives a short overview of copper loop model in DSL (Digital Subscriber Line) environment, its lead testing scenarios and FTTB solution. An explanation of main steps in developing of new model follows. Below that, a discussion model usability and reliability is provided. At the end an experimental verification of the model, which is based on data collecting on physical system in commercial exploitation is done.

This paper through the results of experimental research collected in real system under commercial exploitation investigates the significance of recommended ratio for one of physical layer parameter - SNR margin for the needs of loop qualification for IPTV over xDSL. At the beginning of this paper, a short definition and recommended value for SNR margin is given. In the rest of the paper the measured values of this parameter for 500 xDSL lines and made discussions the practical importance of this parameter for loop qualification are also given.

This paper proposes metrics based on QoS preferences of MNs, and QoS abilities of MAPs, in order to perform a simulative evaluation of the Hierarchical Mobile IPv6 (HMIPv6) network implementation with QoS-aware dynamic MAP selection. The chosen metric meets the desired level of QoS, while retaining MAP load balance, while the DiffServ mechanism ensured the required QoS for HMIPv6 network implementation with QoS-aware dynamic MAP selection.

This paper continues already done research on the possibility for implementation and new test scenarios application for the problems detection in IPTV services delivered over DSL lines. Compared to the previous paper which research it continues, this paper provides a few specific examples of DSL lines in which, based on the values of physical layer parameters, we can assume with great certainty the real cause or a number of possible causes of problems in the IPTV service function. In this way the efficient elimination of identified problems is enabled.

This paper introduces a quite simple and comprehensible model of copper local loop in current DSL applications. The model is useful for engineers and other technical staff, who operate on local loop qualification and troubleshooting in order to evaluate its ability to provide reliable triple play service over DSL quickly. An overview of existing local loop model is presented briefly at the beginning of this paper. Based on pointed shortcomings of those models, a new one, which removes shortcomings, is proposed. A usability of proposed model in present-day conditions, especially in respect to broadband market situation, is analysed briefly.

This paper analyses the test scenarios of monitoring platforms of DSLAM devices and hand-held test instruments in terms of testing the physical layer parameters for the detection of problems in the functioning of the IPTV service. The paper carries out a comparison of both test abilities and analyses the advantages and disadvantages of each in comparison to the other. The paper also suggests optimal use of both test scenarios at very frequent testing on DSL lines.

This paper examines the actual usefulness and importance of longitudinal balance as one of many electrical parameters of symmetrical copper pairs. Through the results of several experiments on copper pairs with different types of significant faults, but also by measuring longitudinal balance on the real system in practice, this paper attempts to show the actual usefulness and importance of this parameter. In this manner, this paper intends to make the process of measuring the electrical parameters of symmetrical copper pairs more reliable and usable for reliable detection of various types of faults.

In spite of all efforts within the IPTV system to implement robust protection mechanisms, attackers manage to find a way to retransmit content to users who do not have right on it so they damage service providers for certain part of the their legal incomes. This paper presents practical examples of abuse of IPTV content. Several scenarios are created, which are based on the fact that subscribers of IPTV service perform abuse of content in a way that they illegally retransmit content which they have paid for or that they illegally record some content. Examples are derived from the author's experience of working on a real IPTV system, security threats and abuse that he is encountered by. Some recommendations are also given, that should be followed by administrators during the establishment of the IPTV system, which decrease potential risks of abuse.

Smart Grid (SG) communication become very hot topic for smart, intelligent and distributed transmission systems for electric power. However, security issues are still open and this is one of main concerns to the deployment of SG. In order to cope with this challenging concern, we propose secure message exchange protocol in this paper, for secure communication in SG system. Particularly, in the proposed protocol, we pay attention to robustness and resistance of exchanged messages to external noise, with a certain level of self-correction. Robustness and resistance to external noise is due to Quick Response (QR) code properties.