Vice Chancellor Prof. Shree Prakash Singh (original) (raw)
Papers by Vice Chancellor Prof. Shree Prakash Singh
2021 3rd International Conference on Signal Processing and Communication (ICPSC)
This paper presents novel closed form expressions for the outage probability and the average bit ... more This paper presents novel closed form expressions for the outage probability and the average bit error for a Cognitive Hybrid FSO/RF system operating in an interference limited environment. Fixed primary RF occupancy and inter-weave cognitive radio principles are employed. The interference arises due to miss detection of the presence of primary RF. Innate optical channel conditions of turbulence and pointing error are considered in this work. The results obtained presents the impact of optical, RF thresholds, interference power and primary channel occupancy on the system performance. The presented analysis showcases the utility of a Cognitive Hybrid FSO/RF link even under interference.
Bookmarks Related papers MentionsView impact
2018 International Conference on Signal Processing and Communications (SPCOM), 2018
The emergence of elastic optical networks (EONs) has been viewed as a solution to the diverse ban... more The emergence of elastic optical networks (EONs) has been viewed as a solution to the diverse bandwidth requests that will occur in the next generation's network applications and Internet which are anticipated to handle a traffic growth at a rate greater than Petabit per second level. However, the crunch in fiber capacity will persist owing to use of only two dimensions of multiplexing in the EONs. With the adoption of space division multiplexing (SDM), an extra freedom degree can be used such that the EONs will be able support the required capacity of the future diverse traffic. Further, with an increase in the rate(s) of transmission(s), to counter the network failures, there will occur the need for protection mechanisms, specifically those, which can protect routes and provision solutions which are end-to-end. In the current work, as an intial step for protecting an EON based on SDM, we design a strategy which (i) is independent of the failure(s), and (ii) protects the route(s). We evaluate our proposed strategy considering realistic assumptions, topologies and parameters, and for different traffic load values. The obtained simulation results reveal that (i) our proposed strategy is efficient in provisioning of protection which is pre-configured, and (ii) the considered network topology's node degree significantly affects both, the blocking and the evaluated route's length in the protected EON based on SDM.
Bookmarks Related papers MentionsView impact
2018 International Conference on Computational and Characterization Techniques in Engineering & Sciences (CCTES), 2018
With advancement in telecommunication technology spectrally efficient modulation formats are used... more With advancement in telecommunication technology spectrally efficient modulation formats are used at high data rates. Long haul network deploy various dispersion compensation mechanisms based on dispersion compensation fiber (DCF). The work presented in this paper explores the suitability of pre, post and symmetrical dispersion compensation techniques at 40Gbps channel in a mixed line rate network. A modified symmetrical dispersion compensation mechanism is proposed and is found to be better than existing dispersion compensation schemes.
Bookmarks Related papers MentionsView impact
International Journal of Advances in Telecommunications, Electrotechnics, Signals and Systems, 2019
The required upgradation of the network capacity of the single-mode fiber which is constrained by... more The required upgradation of the network capacity of the single-mode fiber which is constrained by the non-linear Shannon’s limit, and the capacity provisioning needed by the future diverse Internet traffic can be resolved by the adoption of the Space Division Multiplexing (SDM) based Elastic Optical Networks (EONs) (SDM-b-EONs). In the current work, we focus on the performance analysis of a SDM-b-EON in which translucent lightpaths are routed through the spectral super-channels over the spatial single-mode fiber(s) bundle(s) links. In regard to regeneration, we investigate three scenarios which differ in their regeneration variability level in addition to the adjustment of modulation formats according to transmission route characteristics. We conduct extensive simulations considering an online traffic case and two realistic network topologies with different numbers of (i) fibers in every link, and (ii) transceivers available within SDM-b-EON. The obtained results demonstrate that wh...
Bookmarks Related papers MentionsView impact
2018 IEEE International Conference on Advanced Networks and Telecommunications Systems (ANTS), 2018
The availability of Free Space Optical (FSO) links is limited by weather conditions. To improve o... more The availability of Free Space Optical (FSO) links is limited by weather conditions. To improve overall system availability, an RF link is established in parallel to the FSO link forming a “Hybrid FSO/RF” system. In this conventional Hybrid FSO/RF system, the RF link’s role is limited to that of a back-up link, thus, the RF resource remains largely under-utilized. Since RF resource is scarce, thereby, it is necessary to utilize it to the maximum extent possible. With this aim in mind, we propose and investigate some new system architectures for enhancing utilization of this back-up RF link. Two schemes, namely, “Shared-RF” and “On-Demand” are discussed. These architectures are proposed as some variants of the conventional Hybrid FSO/RF system which help to improve the overall system outage and RF link utilization.
Bookmarks Related papers MentionsView impact
IEEE Transactions on Cognitive Communications and Networking, 2019
Bookmarks Related papers MentionsView impact
IEEE Transactions on Cognitive Communications and Networking, 2019
Bookmarks Related papers MentionsView impact
International Journal of Communication Networks and Distributed Systems, 2020
Bookmarks Related papers MentionsView impact
Journal of Information and Telecommunication, 2018
Bookmarks Related papers MentionsView impact
IETE Journal of Research, 2004
In the first part of this paper [1] we reviewed the non-linear effects present in the optical fib... more In the first part of this paper [1] we reviewed the non-linear effects present in the optical fiber, different types of optical amplifiers available, their limitations and the choice of amplifier for use in long haul WDM systems. It was shown that the number of amplifiers deployed is limited by the noise generated by the amplifiers. Also, the algorithms used for optimal placement of in-line amplifier had been discussed. In the design of the long haul WDM system, wavelength converters play a major role in reducing the blocking probability of the optical network. In this second and concluding part, we review the architecture of wavelength converters. We discuss various analytical models for evaluating blocking probabilities under different conditions and the routing and wavelength assignment schemes. We conclude with the summary of the various algorithms for optimal placement of wavelength converters.
Bookmarks Related papers MentionsView impact
International Journal of Advances in Telecommunications, Electrotechnics, Signals and Systems, 2017
In the existing studies on Mixed Line Rate (MLR) optical networks, the network design methodology... more In the existing studies on Mixed Line Rate (MLR) optical networks, the network design methodology is based on the assumption of deterministic traffic, and hence, the effect of traffic uncertainty on the design of an MLR network remains an open problem of research. In this study, we upgrade our previously proposed cost-efficient mixed integer linear program (MILP) formulation for an MLR network, which considered a specific mean traffic for every network source-destination pair. Our upgraded model employs an optimization technique to account for the traffic uncertainties that an actual MLR optical network may encounter. Our simulation results show that (i) if the MLR network is cost-optimized under the assumption that approximately 10-20% of the demands are at their maximum (or peak) value then, the network demonstrates robustness to traffic peaks in approximately all the other demands, and (ii) the saturation of network cost for a number of source-destination pairs is network topolog...
Bookmarks Related papers MentionsView impact
Journal of Optical Communications, 2017
The ever increasing heterogeneity and growing traffic volume has resulted in significant innovati... more The ever increasing heterogeneity and growing traffic volume has resulted in significant innovations and paradigm shifts within the telecom backbone networks. In order to cost-effectively respond to the diverse variety of traffic requirements having heterogeneous service demands, wavelength division multiplexed (WDM) optical networks have adopted the mixed line rate (MLR) strategy. In MLR networks, many wavelength channels with various line rates can co-exist within the same fiber which, however, raises many important design issues; one of them being the choice of the channel spacing. The quality of signal is affected by the channel spacing in terms of the bit-error rate (BER), which in turn affects the maximum optical reach of the lightpaths that depends on the line rates. In regard to the aforementioned, different methods can be adopted in order to set the width of the channel spacing, viz., (a) choice of a 50 GHz uniform fixed channel spacing specified by the ITU-T grid, (b) expl...
Bookmarks Related papers MentionsView impact
IETE Journal of Research, 2017
ABSTRACT In the current work, with a view on network resilience, we investigate gains which resul... more ABSTRACT In the current work, with a view on network resilience, we investigate gains which result from utilization of the flexible elastic optical networks (EONs). We also focus on an important capability of the EON, viz. the squeezed protection which, in cases of failure(s), minimizes the need for resource(s). We conduct in-depth simulations considering realistic (1) assumptions and (2) topologies, which are characterized by different node(s) numbers, link distances, and corresponding realistic traffic matrices. Through simulations, for the various protection schemes, we compare the fixed-grid wavelength-switched optical networks (WSONs) and the EONs, and the obtained simulation results demonstrate that EONs significantly outperform WSONs. Also, for the considered performance metrics, viz. CapEx/OpEx, power consumption, and spectrum utilization, the WSONs are observed to require more amounts of resources compared to the EONs. Finally, on the one hand, the squeezed protection approach used in EONs is seen to allow for a significant minimization of resources; on the other hand, it only protects a fraction of the traffic.
Bookmarks Related papers MentionsView impact
Photonic Network Communications, 2017
Bookmarks Related papers MentionsView impact
International Journal of Internet Protocol Technology, 2015
Bookmarks Related papers MentionsView impact
2013 National Conference on Communications (NCC), 2013
ABSTRACT In a translucent wavelength division multiplexed (WDM) network, development of an optica... more ABSTRACT In a translucent wavelength division multiplexed (WDM) network, development of an optical control plane (OCP) that is aware of the location and number of available regenerators and all-optical wavelength converters (AOWCs) is of paramount importance. However, generalized multiprotocol label switching (GMPLS) protocol suite does not consider the distribution of regenerator and AOWC information to all network nodes. In this paper, we propose an OCP architecture which disseminates regenerator and AOWC information to all the network nodes. The Physical Layer Impairment-Signal Quality Aware Routing and Wavelength Assignment (PLI-SQARWA) algorithm is employed for RWA. The electro-optical hybrid translucent nodes have been employed which, from a practical perspective, are based on limited range wavelength converters (LRWCs). Performance of the proposed limited range OCP (LR-P-OCP), is compared with the full range OCP (FR-P-OCP) and the hybrid OCP (H-OCP) approach.
Bookmarks Related papers MentionsView impact
J. Opt. Commun., 2013
Bookmarks Related papers MentionsView impact
J. Opt. Commun., 2012
ABSTRACT In all-optical WDM networks, feasibility of a lightpath are determined by physical layer... more ABSTRACT In all-optical WDM networks, feasibility of a lightpath are determined by physical layer impairment accumulation. Physical layer impairment-aware routing and wavelength assignment (PLIA-RWA) algorithms select a feasible route keeping signal to noise ratio value at the receiver above the threshold limit. This paper reviews thenimpairments present in optical fiber emphasizing those that result in performance degradation of WDM system. Different types of channel allocation schemes to reduce the number of four wave mixing components generated and performanceof the WDM optical network under these channel allocation schemes have also been reviewed. The performance of WDM network due to collective effect of FWM SRS and FWM-XPM has been discussed. Limitations of amplifier and its optimal location have also been discussed. The article further examines and surveys the role of wavelength converters/regenerators in regard to efficient network design. The paper also presents a survey of different PLIARWA algorithms and identifies several open problems for future research.
Bookmarks Related papers MentionsView impact
2011 Symposium on Photonics and Optoelectronics (SOPO), 2011
AbstractAll optical WDM system has the benefit of increased transmission distance and high capac... more AbstractAll optical WDM system has the benefit of increased transmission distance and high capacity. The reach of these systems is severely limited by the noise contributed from the combined nonlinear effects inherent in the optical fiber. Of these effects, stimulated ...
Bookmarks Related papers MentionsView impact
Communications and Network, 2012
Bookmarks Related papers MentionsView impact
2021 3rd International Conference on Signal Processing and Communication (ICPSC)
This paper presents novel closed form expressions for the outage probability and the average bit ... more This paper presents novel closed form expressions for the outage probability and the average bit error for a Cognitive Hybrid FSO/RF system operating in an interference limited environment. Fixed primary RF occupancy and inter-weave cognitive radio principles are employed. The interference arises due to miss detection of the presence of primary RF. Innate optical channel conditions of turbulence and pointing error are considered in this work. The results obtained presents the impact of optical, RF thresholds, interference power and primary channel occupancy on the system performance. The presented analysis showcases the utility of a Cognitive Hybrid FSO/RF link even under interference.
Bookmarks Related papers MentionsView impact
2018 International Conference on Signal Processing and Communications (SPCOM), 2018
The emergence of elastic optical networks (EONs) has been viewed as a solution to the diverse ban... more The emergence of elastic optical networks (EONs) has been viewed as a solution to the diverse bandwidth requests that will occur in the next generation's network applications and Internet which are anticipated to handle a traffic growth at a rate greater than Petabit per second level. However, the crunch in fiber capacity will persist owing to use of only two dimensions of multiplexing in the EONs. With the adoption of space division multiplexing (SDM), an extra freedom degree can be used such that the EONs will be able support the required capacity of the future diverse traffic. Further, with an increase in the rate(s) of transmission(s), to counter the network failures, there will occur the need for protection mechanisms, specifically those, which can protect routes and provision solutions which are end-to-end. In the current work, as an intial step for protecting an EON based on SDM, we design a strategy which (i) is independent of the failure(s), and (ii) protects the route(s). We evaluate our proposed strategy considering realistic assumptions, topologies and parameters, and for different traffic load values. The obtained simulation results reveal that (i) our proposed strategy is efficient in provisioning of protection which is pre-configured, and (ii) the considered network topology's node degree significantly affects both, the blocking and the evaluated route's length in the protected EON based on SDM.
Bookmarks Related papers MentionsView impact
2018 International Conference on Computational and Characterization Techniques in Engineering & Sciences (CCTES), 2018
With advancement in telecommunication technology spectrally efficient modulation formats are used... more With advancement in telecommunication technology spectrally efficient modulation formats are used at high data rates. Long haul network deploy various dispersion compensation mechanisms based on dispersion compensation fiber (DCF). The work presented in this paper explores the suitability of pre, post and symmetrical dispersion compensation techniques at 40Gbps channel in a mixed line rate network. A modified symmetrical dispersion compensation mechanism is proposed and is found to be better than existing dispersion compensation schemes.
Bookmarks Related papers MentionsView impact
International Journal of Advances in Telecommunications, Electrotechnics, Signals and Systems, 2019
The required upgradation of the network capacity of the single-mode fiber which is constrained by... more The required upgradation of the network capacity of the single-mode fiber which is constrained by the non-linear Shannon’s limit, and the capacity provisioning needed by the future diverse Internet traffic can be resolved by the adoption of the Space Division Multiplexing (SDM) based Elastic Optical Networks (EONs) (SDM-b-EONs). In the current work, we focus on the performance analysis of a SDM-b-EON in which translucent lightpaths are routed through the spectral super-channels over the spatial single-mode fiber(s) bundle(s) links. In regard to regeneration, we investigate three scenarios which differ in their regeneration variability level in addition to the adjustment of modulation formats according to transmission route characteristics. We conduct extensive simulations considering an online traffic case and two realistic network topologies with different numbers of (i) fibers in every link, and (ii) transceivers available within SDM-b-EON. The obtained results demonstrate that wh...
Bookmarks Related papers MentionsView impact
2018 IEEE International Conference on Advanced Networks and Telecommunications Systems (ANTS), 2018
The availability of Free Space Optical (FSO) links is limited by weather conditions. To improve o... more The availability of Free Space Optical (FSO) links is limited by weather conditions. To improve overall system availability, an RF link is established in parallel to the FSO link forming a “Hybrid FSO/RF” system. In this conventional Hybrid FSO/RF system, the RF link’s role is limited to that of a back-up link, thus, the RF resource remains largely under-utilized. Since RF resource is scarce, thereby, it is necessary to utilize it to the maximum extent possible. With this aim in mind, we propose and investigate some new system architectures for enhancing utilization of this back-up RF link. Two schemes, namely, “Shared-RF” and “On-Demand” are discussed. These architectures are proposed as some variants of the conventional Hybrid FSO/RF system which help to improve the overall system outage and RF link utilization.
Bookmarks Related papers MentionsView impact
IEEE Transactions on Cognitive Communications and Networking, 2019
Bookmarks Related papers MentionsView impact
IEEE Transactions on Cognitive Communications and Networking, 2019
Bookmarks Related papers MentionsView impact
International Journal of Communication Networks and Distributed Systems, 2020
Bookmarks Related papers MentionsView impact
Journal of Information and Telecommunication, 2018
Bookmarks Related papers MentionsView impact
IETE Journal of Research, 2004
In the first part of this paper [1] we reviewed the non-linear effects present in the optical fib... more In the first part of this paper [1] we reviewed the non-linear effects present in the optical fiber, different types of optical amplifiers available, their limitations and the choice of amplifier for use in long haul WDM systems. It was shown that the number of amplifiers deployed is limited by the noise generated by the amplifiers. Also, the algorithms used for optimal placement of in-line amplifier had been discussed. In the design of the long haul WDM system, wavelength converters play a major role in reducing the blocking probability of the optical network. In this second and concluding part, we review the architecture of wavelength converters. We discuss various analytical models for evaluating blocking probabilities under different conditions and the routing and wavelength assignment schemes. We conclude with the summary of the various algorithms for optimal placement of wavelength converters.
Bookmarks Related papers MentionsView impact
International Journal of Advances in Telecommunications, Electrotechnics, Signals and Systems, 2017
In the existing studies on Mixed Line Rate (MLR) optical networks, the network design methodology... more In the existing studies on Mixed Line Rate (MLR) optical networks, the network design methodology is based on the assumption of deterministic traffic, and hence, the effect of traffic uncertainty on the design of an MLR network remains an open problem of research. In this study, we upgrade our previously proposed cost-efficient mixed integer linear program (MILP) formulation for an MLR network, which considered a specific mean traffic for every network source-destination pair. Our upgraded model employs an optimization technique to account for the traffic uncertainties that an actual MLR optical network may encounter. Our simulation results show that (i) if the MLR network is cost-optimized under the assumption that approximately 10-20% of the demands are at their maximum (or peak) value then, the network demonstrates robustness to traffic peaks in approximately all the other demands, and (ii) the saturation of network cost for a number of source-destination pairs is network topolog...
Bookmarks Related papers MentionsView impact
Journal of Optical Communications, 2017
The ever increasing heterogeneity and growing traffic volume has resulted in significant innovati... more The ever increasing heterogeneity and growing traffic volume has resulted in significant innovations and paradigm shifts within the telecom backbone networks. In order to cost-effectively respond to the diverse variety of traffic requirements having heterogeneous service demands, wavelength division multiplexed (WDM) optical networks have adopted the mixed line rate (MLR) strategy. In MLR networks, many wavelength channels with various line rates can co-exist within the same fiber which, however, raises many important design issues; one of them being the choice of the channel spacing. The quality of signal is affected by the channel spacing in terms of the bit-error rate (BER), which in turn affects the maximum optical reach of the lightpaths that depends on the line rates. In regard to the aforementioned, different methods can be adopted in order to set the width of the channel spacing, viz., (a) choice of a 50 GHz uniform fixed channel spacing specified by the ITU-T grid, (b) expl...
Bookmarks Related papers MentionsView impact
IETE Journal of Research, 2017
ABSTRACT In the current work, with a view on network resilience, we investigate gains which resul... more ABSTRACT In the current work, with a view on network resilience, we investigate gains which result from utilization of the flexible elastic optical networks (EONs). We also focus on an important capability of the EON, viz. the squeezed protection which, in cases of failure(s), minimizes the need for resource(s). We conduct in-depth simulations considering realistic (1) assumptions and (2) topologies, which are characterized by different node(s) numbers, link distances, and corresponding realistic traffic matrices. Through simulations, for the various protection schemes, we compare the fixed-grid wavelength-switched optical networks (WSONs) and the EONs, and the obtained simulation results demonstrate that EONs significantly outperform WSONs. Also, for the considered performance metrics, viz. CapEx/OpEx, power consumption, and spectrum utilization, the WSONs are observed to require more amounts of resources compared to the EONs. Finally, on the one hand, the squeezed protection approach used in EONs is seen to allow for a significant minimization of resources; on the other hand, it only protects a fraction of the traffic.
Bookmarks Related papers MentionsView impact
Photonic Network Communications, 2017
Bookmarks Related papers MentionsView impact
International Journal of Internet Protocol Technology, 2015
Bookmarks Related papers MentionsView impact
2013 National Conference on Communications (NCC), 2013
ABSTRACT In a translucent wavelength division multiplexed (WDM) network, development of an optica... more ABSTRACT In a translucent wavelength division multiplexed (WDM) network, development of an optical control plane (OCP) that is aware of the location and number of available regenerators and all-optical wavelength converters (AOWCs) is of paramount importance. However, generalized multiprotocol label switching (GMPLS) protocol suite does not consider the distribution of regenerator and AOWC information to all network nodes. In this paper, we propose an OCP architecture which disseminates regenerator and AOWC information to all the network nodes. The Physical Layer Impairment-Signal Quality Aware Routing and Wavelength Assignment (PLI-SQARWA) algorithm is employed for RWA. The electro-optical hybrid translucent nodes have been employed which, from a practical perspective, are based on limited range wavelength converters (LRWCs). Performance of the proposed limited range OCP (LR-P-OCP), is compared with the full range OCP (FR-P-OCP) and the hybrid OCP (H-OCP) approach.
Bookmarks Related papers MentionsView impact
J. Opt. Commun., 2013
Bookmarks Related papers MentionsView impact
J. Opt. Commun., 2012
ABSTRACT In all-optical WDM networks, feasibility of a lightpath are determined by physical layer... more ABSTRACT In all-optical WDM networks, feasibility of a lightpath are determined by physical layer impairment accumulation. Physical layer impairment-aware routing and wavelength assignment (PLIA-RWA) algorithms select a feasible route keeping signal to noise ratio value at the receiver above the threshold limit. This paper reviews thenimpairments present in optical fiber emphasizing those that result in performance degradation of WDM system. Different types of channel allocation schemes to reduce the number of four wave mixing components generated and performanceof the WDM optical network under these channel allocation schemes have also been reviewed. The performance of WDM network due to collective effect of FWM SRS and FWM-XPM has been discussed. Limitations of amplifier and its optimal location have also been discussed. The article further examines and surveys the role of wavelength converters/regenerators in regard to efficient network design. The paper also presents a survey of different PLIARWA algorithms and identifies several open problems for future research.
Bookmarks Related papers MentionsView impact
2011 Symposium on Photonics and Optoelectronics (SOPO), 2011
AbstractAll optical WDM system has the benefit of increased transmission distance and high capac... more AbstractAll optical WDM system has the benefit of increased transmission distance and high capacity. The reach of these systems is severely limited by the noise contributed from the combined nonlinear effects inherent in the optical fiber. Of these effects, stimulated ...
Bookmarks Related papers MentionsView impact
Communications and Network, 2012
Bookmarks Related papers MentionsView impact