With the rapid growth of the telecom sector heading towards 5G and 6G and the emergence of high-b... more With the rapid growth of the telecom sector heading towards 5G and 6G and the emergence of high-bandwidth and time-sensitive applications, mobile network operators (MNOs) are driven to plan their networks to meet these new requirements in a cost-effective manner. The cloud radio access network (CRAN) has been presented as a promising architecture that can decrease capital expenditures (Capex) and operating expenditures (Opex) and improve network performance. The fronthaul (FH) is a part of the network that links the remote radio head (RRH) to the baseband unit (BBU); these links need high-capacity and low latency connections necessitating costeffective implementation. On the other hand, the transport delay and FH deployment costs increase if the BBU is not placed in an appropriate location. In this paper, we propose an integer linear program (ILP) that simultaneously optimizes BBU and FH deployment resulting in minimal capital expenditures (Capex). Simulations are run to compare the...
The modern technological innovations provide small radios with ability to broadcast over vast are... more The modern technological innovations provide small radios with ability to broadcast over vast areas with minimum energy consumption that will significantly influence the future of the Internet of Things (IoT) communications. The majority of IoT implementations demand sensor nodes run reliably for an extended time. Furthermore, the radio settings can endure a high data rate transmission while optimizing the energy-efficiency. The LoRa/LoRaWAN is one of the primary Low-Power Wide Area Network (LPWAN) technology that has highly enticed much concentration recently from the community. The energy limits is a significant issue in wireless sensor networks since battery lifetime that supplies sensor nodes have a restricted amount of energy and neither expendable nor rechargeable in most cases. A common hypothesis in previous work is that the energy consumed by sensors in sleep mode is negligible. With this hypothesis, the usual approach is to consider subsets of nodes that reach all the iter...
Graphs and Algorithms in Communication Networks, 2009
In an optical network using the wavelength division multiplexing (WDM) technology, routing a requ... more In an optical network using the wavelength division multiplexing (WDM) technology, routing a request consists of assigning it a route in the physical network and a wavelength. If each request uses 1/g of the bandwidth of the wavelength, we will say that the grooming factor is g. That means that on a given edge of the network we can groom (group) at most g requests on the same wavelength. With this constraint the objective can be either to minimize the number of wavelengths (related to the transmission cost) or minimize the number of Add/Drop Multiplexers (shortly ADM) used in the network (related to the cost of the nodes). Here, we first survey the main theoretical results obtained for different grooming
2018 IEEE International Conference on Future IoT Technologies (Future IoT), 2018
Internet of things (IoT) becomes a prominent technology in our world. It is enabling the connecti... more Internet of things (IoT) becomes a prominent technology in our world. It is enabling the connection between the objects (the "things") and the backend systems via the Internet. Everyday objects can become connected and smart. It has been adopted in different areas and applications such as smart cities, smart agriculture, smart healthcare, smart manufacturing, and others. Moreover, IoT platforms are currently growing up into the market. Each platform provides valuable and specific services and features. This paper presents a survey on IoT platforms, discussing their architectures and fundamentals of IoT building elements and communication protocols between them. The aim of this paper is to help the reader choose a suitable and adequate IoT platform for own demands in the huge number and variety of platforms available. This survey provides a comprehensive view of the components and features of the state-of-the-art IoT platforms.
In our paper we analysed algorithms that seek the optimal routing configuration in backbone netwo... more In our paper we analysed algorithms that seek the optimal routing configuration in backbone networks with capacity constraints. We investigated a special case when multiple full mesh demand sets (forming Virtual Private Networks (VPNs)) have to be built.
Shared Segment Protection (SSP), compared with Shared Path Protection (SPP), and Shared Link Prot... more Shared Segment Protection (SSP), compared with Shared Path Protection (SPP), and Shared Link Protection (SLP), provides an optimal protection configuration due to the ability of maximizing spare capacity sharing, and reducing the restoration time in cases of a single link failure. This paper provides a thorough study on SSP under the GMPLS-based recovery framework, where an effective survivable routing algorithm for SSP is proposed. The tradeoff between the price (i.e., cost representing the amount of resources, and the blocking probability), and the restoration time is extensively studied by simulations on three networks with highly dynamic traffic. We demonstrate that the proposed survivable routing algorithm can be a powerful solution for meeting stringent delay upper bounds for achieving high restorability of transport services. This can significantly improve the network reliability, and enable more advanced, mission critical services in the networks. The comparison among the th...
Journal of telecommunications and information technology, 2004
The bit rate of modern applications typically varies in time. We consider the traffic elastic if ... more The bit rate of modern applications typically varies in time. We consider the traffic elastic if the rate of the sources can be controlled as a function of free resources along the route of that traffic. The objective is to route the demands optimally in sense of increasing the total network throughput while setting the rates of sources in a fair way. We propose a new fairness definition the relative fairness that handles lower and upper bounds on the traffic rate of each source and we compare it with two other known fairness definitions, namely, the max-min and the proportional rate fairness. We propose and compare different routing algorithms, all with three types of fairness definitions. The algorithms are all a tradeoff between network throughput, fairness and computational time. Keywords—elastic traffic, routing, fairness, maximum throughput, algorithms, ILP, heuristics.
The new era of IoT brings the necessity of smart synergy for diverse communication and computatio... more The new era of IoT brings the necessity of smart synergy for diverse communication and computation entities. The two extremes are, on the one hand, the 5G Ultra-Reliable Low-Latency Communications (URLLC) required for Industrial IoT (IIoT) and Vehicle Communications (V2V, V2I, V2X). While on the other hand, the Ultra-Low Power, Wide-Range, Low Bit-rate Communications, such as Sigfox, LoRa/LoRaWAN, NB-IoT, Cat-M1, etc.; used for smart metering, smart logistics, monitoring, alarms, tracking applications. This extreme variety and diversity must work in synergy, all inter-operating/inter-working with the Internet. The communication solutions must mutually cooperate, but there must be a synergy in a broader sense that includes the various communication solutions and all the processing and storage capabilities from the edge cloud to the deep-cloud. In this paper, we consider a non-orthogonal multiple access (NOMA)-based device to device (D2D) communication system coexisting with a cellula...
This paper discusses the evolution of optical systems starting from WDM links to Optical Packet S... more This paper discusses the evolution of optical systems starting from WDM links to Optical Packet Switching Networks via some stages as Switched Optical Networks, Multilayer Networks with either traffic or wavelength grooming, Optical VPNs and Optical Burst Switching. We discuss the advantages and drawbacks of certain approaches since the future developments of optical networking technology might influence this evolution. We also draw our near-term and long-term visions of optical networking.
Recently - for economical and ecological reasons -, energy-efficiency has been receiving an emerg... more Recently - for economical and ecological reasons -, energy-efficiency has been receiving an emerging attention from both industrial and fundamental researchers. Given the large-scale growth and resource overprovision of communication networks, the issues related to energy consumption get more significant than ever. In this paper, we provide an overview of some of the latest contributions and most important trends on energy-efficient networking. Since today's networks are heterogeneous to a large extent, different concepts and aspects of networking are discussed in separate sections. Following the introduction of the fundamental discipline of energy-proportional computing (and also its relationship with resource over-provisioning), we give an overview on the power-saving opportunities of core networks with focusing on two of the most-widely applied techniques for energy management. A comparison of circuit and packet switched networking approaches is also made, along with some con...
This chapter discusses vital techniques to enhance the resilience of 5G systems. It starts with d... more This chapter discusses vital techniques to enhance the resilience of 5G systems. It starts with dependability assessment of 5G networks. Next, it describes (a) the frequency fallback technique to improve availability and survivability of 5G services, (b) segment interleaving scheme to enhance communications resilience between base stations and the remaining part of the network and (c) multi-operator protection to address the resilience issues in a multi-operator scenario when one of the operators fails to deliver services, and the backup service can be provided to its users by another operator. Finally, it focuses on energy-aware techniques for dynamic management of base station configuration and of load distribution aimed at maximizing network survivability in case of disaster.
VIII dc_357_11 2.6 Relative frequency histogram of the number of free (unused) ports. Examples fo... more VIII dc_357_11 2.6 Relative frequency histogram of the number of free (unused) ports. Examples for under-utilised (left), optimally utilised (middle) and over-utilised (right) nodes.. .. 45 2.7 Relative frequency histogram of the free capacity of links. Example for a lightly (left)
1 This work has been partially supported by Ericsson 2 Department of Telecommunications and Telem... more 1 This work has been partially supported by Ericsson 2 Department of Telecommunications and Telematics, Technical University of Budapest, Sztoczek u. 2, H-1111 Budapest, Hungary, E-mail: cinkler@ttt-atm.ttt.bme.hu, Tel: +(36) 1 463-1861 Fax: +(36) 1 463-3107 3 Ericsson Telecom AB, Reference Lab, Tellusborgswagen, S-12625 Stockholm, Sweden 4 Ericsson Telecom AB, Network Design Lab, Telefonplan, S-12625 Stockholm, Sweden ABSTRACT: A heuristic algorithm is proposed for Network Design. The position of nodes, the traffic matrix and the cost-functions for connecting node-pairs by a direct link are given as input. The constraint is that network has to be able to survive any n-1 node or link failure. The algorithm results in an n-connected network with the set of n vertex-disjoint (or edge-disjoint) paths for each node-pair, and link capacities. Because of the problem complexity, the global optimum is not guaranteed, but the result can be obtained in polynomial time. The novelty of this app...
An e cient, network-ow-theory based model with an algorithm is proposed for con guration of netwo... more An e cient, network-ow-theory based model with an algorithm is proposed for con guration of networks. The con guration results in a structure of paths which can survive any single link failure. For each node-pair two link-or node-disjoint paths are obtained: A working one and one used for backup when a failure a ects the direct one. The subject of minimisation is the length of working paths, and the total capacity used for both, working and backup paths. We compare results obtained by three methods: First, the problem has been formulated as an Integer Linear Program (ILP) and solved by CPLEX. Second, a heuristic method called Iterative Capacity Splitting (ICS) has been worked out. Third, a randomised method called Simulated Allocation (SA) proposed by M. Pioro has been implemented. Furthermore, we present simple heuristics for improving the performance of Simulated Allocation. For minimising the total amount of allocated capacity we propose a method referred to as TCA for reducing the capacity allocation, which can be applied to all three methods. The signi cance of the TCA method is that around 40% of the total capacity can be saved! The obtained results can be used for con guration of SDH, ATM, WDM and other networks.
1 Abstract—As the modern networks consist of multiple layers (stacked networks), appropriate, mul... more 1 Abstract—As the modern networks consist of multiple layers (stacked networks), appropriate, multi-layer traffic engineering schemes are required [1]. This paper presents a few techniques of interest that can be classified into 'a priori', 'a posteriori' and 'joint' schemes. We discuss an 'a posteriori' scheme, the λ-path fragmentation and de-fragmentation, in more details. It gives very high revenue in throughput compared to the simpler 'a priori' schemes, while the 'joint' scheme where both 'a priory' and 'a posteriori' principles are employed gives only slightly higher throughput than the 'a posteriori' one however it requires much more λ-path fragmentation and de-fragmentation operations.
The massive increase in the Internet of Things (IoT) has brought a diverse long-range, low-power,... more The massive increase in the Internet of Things (IoT) has brought a diverse long-range, low-power, and low bit-rate wireless network technologies. The LoRa a low-power wide area network (LPWAN) gained popularity as radio technology for the realization of many IoT applications. LoRa is typically employed together with LoRaWAN MAC protocol and operates in the license-free ISM bands. LoRa networks have an issue with scalability when the number of end nodes connected to one network is larger than the shared number of channels, that causes a collision and packets loss through receiving a wide range of different message sizes from various application. In this paper, we describe an accurate and efficient way confirmed by simulation to calculate the probability of collision rate and packet loss in LPWANs under various circumstances. Moreover, based on the LoRaWAN specification, we consider a dense network deployment of IoT devices. In the event of collisions, our proposed algorithms is class...
5G New Radio allows operators to use new and wider spectrum and complements Long-Term Evolution n... more 5G New Radio allows operators to use new and wider spectrum and complements Long-Term Evolution networks with higher data rates and lower latency. Supporting such requirements in the transport network is not only a technological challenge, but a financial one as well. The use of high-frequency or unlicensed spectrum and cell densification for capacity increases call for adoption of small cells. This means that the transport network needs to connect a large number of devices, which leads to high deployment costs. Improving resilience by redundancy would further inflate these cost. In this paper, we examine the prospect of enhancing resilience via an interleaved photonic transport network as well as by the cooperation of multiple operators. Resilience is quantified by the decrease in availability in case of a failure. Furthermore, we also investigate the case when the number of active cells is reduced not by failure, but due to deliberate switch-off in order to save power.
2011 3rd International Congress on Ultra Modern Telecommunications and Control Systems and Workshops, 2011
ABSTRACT In optical networks, according to the latest tendencies, the goal is to route all demand... more ABSTRACT In optical networks, according to the latest tendencies, the goal is to route all demands in all-optical way. However, in the near future, this will still not be possible due to technical constraints and backward compatibility. In the meantime, operators may decide to reserve a given percent of their power budget for all-optical routing, while the rest of the budget is used as it is done now. This introduces a new, additional problem. Namely, operators have to select which demands should be routed in all-optical way. This problem is even more complex for demands that need protection. In this paper, we present methods that may help operators to maximize the number of demands with protection routed in all-optical way. Based on simulations, we show the beneficial properties of the proposed approaches.
With the rapid growth of the telecom sector heading towards 5G and 6G and the emergence of high-b... more With the rapid growth of the telecom sector heading towards 5G and 6G and the emergence of high-bandwidth and time-sensitive applications, mobile network operators (MNOs) are driven to plan their networks to meet these new requirements in a cost-effective manner. The cloud radio access network (CRAN) has been presented as a promising architecture that can decrease capital expenditures (Capex) and operating expenditures (Opex) and improve network performance. The fronthaul (FH) is a part of the network that links the remote radio head (RRH) to the baseband unit (BBU); these links need high-capacity and low latency connections necessitating costeffective implementation. On the other hand, the transport delay and FH deployment costs increase if the BBU is not placed in an appropriate location. In this paper, we propose an integer linear program (ILP) that simultaneously optimizes BBU and FH deployment resulting in minimal capital expenditures (Capex). Simulations are run to compare the...
The modern technological innovations provide small radios with ability to broadcast over vast are... more The modern technological innovations provide small radios with ability to broadcast over vast areas with minimum energy consumption that will significantly influence the future of the Internet of Things (IoT) communications. The majority of IoT implementations demand sensor nodes run reliably for an extended time. Furthermore, the radio settings can endure a high data rate transmission while optimizing the energy-efficiency. The LoRa/LoRaWAN is one of the primary Low-Power Wide Area Network (LPWAN) technology that has highly enticed much concentration recently from the community. The energy limits is a significant issue in wireless sensor networks since battery lifetime that supplies sensor nodes have a restricted amount of energy and neither expendable nor rechargeable in most cases. A common hypothesis in previous work is that the energy consumed by sensors in sleep mode is negligible. With this hypothesis, the usual approach is to consider subsets of nodes that reach all the iter...
Graphs and Algorithms in Communication Networks, 2009
In an optical network using the wavelength division multiplexing (WDM) technology, routing a requ... more In an optical network using the wavelength division multiplexing (WDM) technology, routing a request consists of assigning it a route in the physical network and a wavelength. If each request uses 1/g of the bandwidth of the wavelength, we will say that the grooming factor is g. That means that on a given edge of the network we can groom (group) at most g requests on the same wavelength. With this constraint the objective can be either to minimize the number of wavelengths (related to the transmission cost) or minimize the number of Add/Drop Multiplexers (shortly ADM) used in the network (related to the cost of the nodes). Here, we first survey the main theoretical results obtained for different grooming
2018 IEEE International Conference on Future IoT Technologies (Future IoT), 2018
Internet of things (IoT) becomes a prominent technology in our world. It is enabling the connecti... more Internet of things (IoT) becomes a prominent technology in our world. It is enabling the connection between the objects (the "things") and the backend systems via the Internet. Everyday objects can become connected and smart. It has been adopted in different areas and applications such as smart cities, smart agriculture, smart healthcare, smart manufacturing, and others. Moreover, IoT platforms are currently growing up into the market. Each platform provides valuable and specific services and features. This paper presents a survey on IoT platforms, discussing their architectures and fundamentals of IoT building elements and communication protocols between them. The aim of this paper is to help the reader choose a suitable and adequate IoT platform for own demands in the huge number and variety of platforms available. This survey provides a comprehensive view of the components and features of the state-of-the-art IoT platforms.
In our paper we analysed algorithms that seek the optimal routing configuration in backbone netwo... more In our paper we analysed algorithms that seek the optimal routing configuration in backbone networks with capacity constraints. We investigated a special case when multiple full mesh demand sets (forming Virtual Private Networks (VPNs)) have to be built.
Shared Segment Protection (SSP), compared with Shared Path Protection (SPP), and Shared Link Prot... more Shared Segment Protection (SSP), compared with Shared Path Protection (SPP), and Shared Link Protection (SLP), provides an optimal protection configuration due to the ability of maximizing spare capacity sharing, and reducing the restoration time in cases of a single link failure. This paper provides a thorough study on SSP under the GMPLS-based recovery framework, where an effective survivable routing algorithm for SSP is proposed. The tradeoff between the price (i.e., cost representing the amount of resources, and the blocking probability), and the restoration time is extensively studied by simulations on three networks with highly dynamic traffic. We demonstrate that the proposed survivable routing algorithm can be a powerful solution for meeting stringent delay upper bounds for achieving high restorability of transport services. This can significantly improve the network reliability, and enable more advanced, mission critical services in the networks. The comparison among the th...
Journal of telecommunications and information technology, 2004
The bit rate of modern applications typically varies in time. We consider the traffic elastic if ... more The bit rate of modern applications typically varies in time. We consider the traffic elastic if the rate of the sources can be controlled as a function of free resources along the route of that traffic. The objective is to route the demands optimally in sense of increasing the total network throughput while setting the rates of sources in a fair way. We propose a new fairness definition the relative fairness that handles lower and upper bounds on the traffic rate of each source and we compare it with two other known fairness definitions, namely, the max-min and the proportional rate fairness. We propose and compare different routing algorithms, all with three types of fairness definitions. The algorithms are all a tradeoff between network throughput, fairness and computational time. Keywords—elastic traffic, routing, fairness, maximum throughput, algorithms, ILP, heuristics.
The new era of IoT brings the necessity of smart synergy for diverse communication and computatio... more The new era of IoT brings the necessity of smart synergy for diverse communication and computation entities. The two extremes are, on the one hand, the 5G Ultra-Reliable Low-Latency Communications (URLLC) required for Industrial IoT (IIoT) and Vehicle Communications (V2V, V2I, V2X). While on the other hand, the Ultra-Low Power, Wide-Range, Low Bit-rate Communications, such as Sigfox, LoRa/LoRaWAN, NB-IoT, Cat-M1, etc.; used for smart metering, smart logistics, monitoring, alarms, tracking applications. This extreme variety and diversity must work in synergy, all inter-operating/inter-working with the Internet. The communication solutions must mutually cooperate, but there must be a synergy in a broader sense that includes the various communication solutions and all the processing and storage capabilities from the edge cloud to the deep-cloud. In this paper, we consider a non-orthogonal multiple access (NOMA)-based device to device (D2D) communication system coexisting with a cellula...
This paper discusses the evolution of optical systems starting from WDM links to Optical Packet S... more This paper discusses the evolution of optical systems starting from WDM links to Optical Packet Switching Networks via some stages as Switched Optical Networks, Multilayer Networks with either traffic or wavelength grooming, Optical VPNs and Optical Burst Switching. We discuss the advantages and drawbacks of certain approaches since the future developments of optical networking technology might influence this evolution. We also draw our near-term and long-term visions of optical networking.
Recently - for economical and ecological reasons -, energy-efficiency has been receiving an emerg... more Recently - for economical and ecological reasons -, energy-efficiency has been receiving an emerging attention from both industrial and fundamental researchers. Given the large-scale growth and resource overprovision of communication networks, the issues related to energy consumption get more significant than ever. In this paper, we provide an overview of some of the latest contributions and most important trends on energy-efficient networking. Since today's networks are heterogeneous to a large extent, different concepts and aspects of networking are discussed in separate sections. Following the introduction of the fundamental discipline of energy-proportional computing (and also its relationship with resource over-provisioning), we give an overview on the power-saving opportunities of core networks with focusing on two of the most-widely applied techniques for energy management. A comparison of circuit and packet switched networking approaches is also made, along with some con...
This chapter discusses vital techniques to enhance the resilience of 5G systems. It starts with d... more This chapter discusses vital techniques to enhance the resilience of 5G systems. It starts with dependability assessment of 5G networks. Next, it describes (a) the frequency fallback technique to improve availability and survivability of 5G services, (b) segment interleaving scheme to enhance communications resilience between base stations and the remaining part of the network and (c) multi-operator protection to address the resilience issues in a multi-operator scenario when one of the operators fails to deliver services, and the backup service can be provided to its users by another operator. Finally, it focuses on energy-aware techniques for dynamic management of base station configuration and of load distribution aimed at maximizing network survivability in case of disaster.
VIII dc_357_11 2.6 Relative frequency histogram of the number of free (unused) ports. Examples fo... more VIII dc_357_11 2.6 Relative frequency histogram of the number of free (unused) ports. Examples for under-utilised (left), optimally utilised (middle) and over-utilised (right) nodes.. .. 45 2.7 Relative frequency histogram of the free capacity of links. Example for a lightly (left)
1 This work has been partially supported by Ericsson 2 Department of Telecommunications and Telem... more 1 This work has been partially supported by Ericsson 2 Department of Telecommunications and Telematics, Technical University of Budapest, Sztoczek u. 2, H-1111 Budapest, Hungary, E-mail: cinkler@ttt-atm.ttt.bme.hu, Tel: +(36) 1 463-1861 Fax: +(36) 1 463-3107 3 Ericsson Telecom AB, Reference Lab, Tellusborgswagen, S-12625 Stockholm, Sweden 4 Ericsson Telecom AB, Network Design Lab, Telefonplan, S-12625 Stockholm, Sweden ABSTRACT: A heuristic algorithm is proposed for Network Design. The position of nodes, the traffic matrix and the cost-functions for connecting node-pairs by a direct link are given as input. The constraint is that network has to be able to survive any n-1 node or link failure. The algorithm results in an n-connected network with the set of n vertex-disjoint (or edge-disjoint) paths for each node-pair, and link capacities. Because of the problem complexity, the global optimum is not guaranteed, but the result can be obtained in polynomial time. The novelty of this app...
An e cient, network-ow-theory based model with an algorithm is proposed for con guration of netwo... more An e cient, network-ow-theory based model with an algorithm is proposed for con guration of networks. The con guration results in a structure of paths which can survive any single link failure. For each node-pair two link-or node-disjoint paths are obtained: A working one and one used for backup when a failure a ects the direct one. The subject of minimisation is the length of working paths, and the total capacity used for both, working and backup paths. We compare results obtained by three methods: First, the problem has been formulated as an Integer Linear Program (ILP) and solved by CPLEX. Second, a heuristic method called Iterative Capacity Splitting (ICS) has been worked out. Third, a randomised method called Simulated Allocation (SA) proposed by M. Pioro has been implemented. Furthermore, we present simple heuristics for improving the performance of Simulated Allocation. For minimising the total amount of allocated capacity we propose a method referred to as TCA for reducing the capacity allocation, which can be applied to all three methods. The signi cance of the TCA method is that around 40% of the total capacity can be saved! The obtained results can be used for con guration of SDH, ATM, WDM and other networks.
1 Abstract—As the modern networks consist of multiple layers (stacked networks), appropriate, mul... more 1 Abstract—As the modern networks consist of multiple layers (stacked networks), appropriate, multi-layer traffic engineering schemes are required [1]. This paper presents a few techniques of interest that can be classified into 'a priori', 'a posteriori' and 'joint' schemes. We discuss an 'a posteriori' scheme, the λ-path fragmentation and de-fragmentation, in more details. It gives very high revenue in throughput compared to the simpler 'a priori' schemes, while the 'joint' scheme where both 'a priory' and 'a posteriori' principles are employed gives only slightly higher throughput than the 'a posteriori' one however it requires much more λ-path fragmentation and de-fragmentation operations.
The massive increase in the Internet of Things (IoT) has brought a diverse long-range, low-power,... more The massive increase in the Internet of Things (IoT) has brought a diverse long-range, low-power, and low bit-rate wireless network technologies. The LoRa a low-power wide area network (LPWAN) gained popularity as radio technology for the realization of many IoT applications. LoRa is typically employed together with LoRaWAN MAC protocol and operates in the license-free ISM bands. LoRa networks have an issue with scalability when the number of end nodes connected to one network is larger than the shared number of channels, that causes a collision and packets loss through receiving a wide range of different message sizes from various application. In this paper, we describe an accurate and efficient way confirmed by simulation to calculate the probability of collision rate and packet loss in LPWANs under various circumstances. Moreover, based on the LoRaWAN specification, we consider a dense network deployment of IoT devices. In the event of collisions, our proposed algorithms is class...
5G New Radio allows operators to use new and wider spectrum and complements Long-Term Evolution n... more 5G New Radio allows operators to use new and wider spectrum and complements Long-Term Evolution networks with higher data rates and lower latency. Supporting such requirements in the transport network is not only a technological challenge, but a financial one as well. The use of high-frequency or unlicensed spectrum and cell densification for capacity increases call for adoption of small cells. This means that the transport network needs to connect a large number of devices, which leads to high deployment costs. Improving resilience by redundancy would further inflate these cost. In this paper, we examine the prospect of enhancing resilience via an interleaved photonic transport network as well as by the cooperation of multiple operators. Resilience is quantified by the decrease in availability in case of a failure. Furthermore, we also investigate the case when the number of active cells is reduced not by failure, but due to deliberate switch-off in order to save power.
2011 3rd International Congress on Ultra Modern Telecommunications and Control Systems and Workshops, 2011
ABSTRACT In optical networks, according to the latest tendencies, the goal is to route all demand... more ABSTRACT In optical networks, according to the latest tendencies, the goal is to route all demands in all-optical way. However, in the near future, this will still not be possible due to technical constraints and backward compatibility. In the meantime, operators may decide to reserve a given percent of their power budget for all-optical routing, while the rest of the budget is used as it is done now. This introduces a new, additional problem. Namely, operators have to select which demands should be routed in all-optical way. This problem is even more complex for demands that need protection. In this paper, we present methods that may help operators to maximize the number of demands with protection routed in all-optical way. Based on simulations, we show the beneficial properties of the proposed approaches.
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Papers by Tibor Cinkler