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The blocking probability is studied for improving the quality of service of the network. The call blocking model for mode of operation to determine the types of applications suitable for Generalized Multi-Protocol Label Switched (GMPLS) networks is proposed. The performance of optical network depends upon various parameters such as number of channels, number of sources, traffic intensity which directly affect the blocking probability of the network. A mathematical model of an optical network for blocking probability of cleared calls and holding calls is developed. In the proposed model, blocking probability of the network gets reduced with a large number of servers. The proposed models decrease the blocking probability of the network to a level of 10–40. In addition, the blocking performance for held calls is also analyzed to compare the amount of traffic intensity that can be handled and completed properly with that of the cleared calls probability. The blocking probability is less for cleared calls than that for held calls as more traffic intensity can be handled in case of cleared calls but the chances for call completion increases in case of held calls. [ABSTRACT FROM AUTHOR]

Optical amplifiers are developed to boost up the performance of the communication systems. Amplifiers such as erbium doped fiber amplifier (EDFA), RAMAN and semiconductor optical amplifier (SOA) are used for this purpose. It is mandatory to use optical amplifiers for signal transmission to long distances. In this paper, the hybrid optical amplifier EDFA-RAMAN-EDFA is proposed to enhance the signal quality received at receiver end and to initiate the efficient transmission of 8 × 10 Gbps transmission speed for wavelength division multiplexed (WDM) system. The proposed mechanism is evaluated with respect to various parameters such as quality factor, eye-height, and bit error rate (BER) and eye diagram considering various values of transmission distance ranging from 100 to 200 km. The analysis shows that the proposed mechanism has better quality factor value and minimum BER value than the traditional approach. Wider eye opening for proposed technique represents that the distortions produced in the system are least. [ABSTRACT FROM AUTHOR]

Generalized multiprotocol Label Switching (GMPLS) is a set of rules which is used in various layers like the Wavelength Division Multiplexing (WDM) layer, Time Division Multiplexing (TDM) layer, etc. to generalize the concepts of labels of Multiprotocol Label Switching networks. A block in call occurs when number of requests is more than the servers and waiting rooms. This call blocking is the very important parameter and can be calculated in terms of probability. There are a number of models to calculate the call blocking probability like Erlang B, Erlang C, etc. This paper suggests a novel, efficient and less – complex model which minimize the call blocking to very much extent for GMPLS networks. This model deals with the factors like number of wavelengths, number of links, traffic intensity, etc. which can help in reducing the call blocking probability and give better results. In this paper, the call-blocking probability is also compared with number of links by considering different wavelengths. A comparison of call-blocking probability of proposed model is also analysed. This paper deals with blocking probability optimization in GMPLS Networks using Fredericks approach. We have used peakedness factor from Fredericks approach in Engset's formula for this optimization." [ABSTRACT FROM AUTHOR]

Passive optical network (PON)-supported orthogonal frequency-division multiplexing is viewed as a capable answer designed for subsequent generation optical networks in terms of traffic coloring when integrated with monarch butterfly optimization (MBO). Traffic coloring optimization (TCO) or MBO algorithmic rule solves the matter of controlling the traffic, began by end-user transceivers with multiple parameters through rescheduling transmission capacity and bandwidth allocation strategy of the optical network, which are done by means of its operator functions. The TCO method with granularity adjustment components outcome signifies an improvement in quality of service as it reduces jitter and increases throughput in PON by 350 µs and 12.5 %, respectively. It even improves the blocking probability and fairness index. [ABSTRACT FROM AUTHOR]

In this paper, a competent flat gain hybrid optical amplifier is proposed with an optimum arrangement of erbium doped fiber amplifier (EDFA) and Raman amplifier. Attempts are made to design a hybrid optical amplifier for100 channels, 10 Gbps super dense wavelength division multiplexed (SDWDM) systems at channel spacing of 0.1 nm. Work capacity of the system was compared on the basis of various parameters, viz., noise figure and gain that determined the performance of the system. The gain spectrum of the hybrid optical amplifier depends upon the parameters viz., laser input power, pump power and pump wavelength of the amplifier. It was found that for wavelength range 1,560.38–1,579.59 nm, a flat gain of 4.34 dB is achieved for input power of −10 dB with noise figure variation of 0.818 dB without using any gain flattering scheme. Being simple and cost effective, this hybrid optical amplifier could be recommended for gain flatness characteristics and acceptable noise figure for dense wavelength multiplexed systems. [ABSTRACT FROM AUTHOR]

Large capacity optical networks require flattened gain spectrum and large gain bandwidth of the optical networks. In order to achieve this large number of hybrid optical amplifiers are designed. Here we proposed a competent flat gain hybrid optical amplifier with an optimum combination of Erbium Doped Fiber Amplifier (EDFA) and Raman amplifier. Attempts are made to design a hybrid optical amplifier for 100 channels, 10 Gbps Super Dense Wavelength Division Multiplexed (SDWDM) systems at different channel spacing of 0.1, 0.2, 0.4 and 0.8 nm. Work capacity of the network was compared on the basis of various parameters viz., gain and noise figure that determined the performance of the system. The gain spectrum of the hybrid optical amplifier depends upon the parameters viz., pump wavelength, pump power and laser input power of the amplifier. Various efforts were conceded out to optimize these parameters. It was found that for wavelength range 1,570.5–1,580.75 nm, a flat gain of 5.36 dB is achieved for input power of −15 dB with noise figure variation of 0.57 dB without using any gain flattering scheme. Being simple and cost effective, this hybrid optical amplifier could be recommended for gain flatness characteristics and acceptable noise figure for super dense wavelength division multiplexed system. [ABSTRACT FROM AUTHOR]

Passive optical network (PON) supported orthogonal frequency division multiplexing is a network that is designed for subsequent generation of optical networks. During this work, the proposed algorithm consists of neurofuzzy rules which update and control the minimum bandwidth allocation granularity g \left(g \right). In order to improve the quality of service, a biogeography-based optimization algorithm is introduced and a new fitness function is proposed which reduces the round trip time by enhancing the distribution scaling factor. Hence, the proposed work reduces the jitter and increases the throughput of the PON for fixed g = 1 g = 1 which enhances the network performance by 3.4 % and 1.23 %, respectively. [ABSTRACT FROM AUTHOR]

In this paper, link fault tolerant algorithms (LFTAs) are employed for optimization of blocking performance in optical burst switching (OBS) networks for dynamic establishment of wavelength-routed lightpaths. This paper presents two algorithms: link fault tolerance algorithm for least congestion (LFTALC) and link fault tolerance algorithm for optimized blocking (LFTAOB). In former algorithm, the path with least congestion is selected and in the latter algorithm the path with least blocking probability is selected and then both the algorithms check for the availability of fault on the links present in the selected path. The findings indicate that methods of developing link based fault tolerant algorithms keep good performance and fairness among all the connections. The key advantage of these proposed algorithms as compared to routing and wavelength assignment algorithm is that these are very simple in nature and require less service disruption time. [ABSTRACT FROM AUTHOR]

The call blocking is the most vital factor in generalized multiprotocol label switching (GMPLS) Networks. Call blocking depends upon many factors such as traffic intensity, number of servers and number of links. Call blocking performance for GMPLS networks has been calculated in this paper by using a proposed mathematical model. The proposed model investigates the dependency of probability of call blocking upon the number of wavelengths and number of links. In the suggested model, the blocking performance of GMPLS network is improved. [ABSTRACT FROM AUTHOR]

The proposed traffic grooming methodology for long-reach-passive optical networks will decrease the latency in upstream. The scheduling and wavelength assignment for ethernet passive optical networks has been shown to perform much better in terms of delay. The dynamic traffic grooming algorithm based on intelligent water drop is proposed in which new depositions function has been introduced for efficient handling of bandwidth. Therefore, once equally distanced optical network units were scheduled on constant wavelengths, the void formation impact is reduced. The outcomes conjointly depict the result of the planned methodology on bandwidth utilization improvement and jitter by 1.46 and 408.66 µs improvements respectively, even overall latency is improved by 465.83 µs by value. These results depict the validity of the planned dynamic bandwidth allocation methodology for traffic grooming. [ABSTRACT FROM AUTHOR]

Optical networks were invented by the developing and developed nations in order to extend the capacity required for communication systems in a worthwhile way. In this paper, the attempt is done to improve the capacity and performance of semiconductor optical amplifier, Raman and erbium-doped fiber amplifier (EDFA) amplifiers used in optical networks. The potential of different optical amplifiers operating at 8×10 Gbps has been examined and their performance was compared on behalf of different parameters, viz. eye opening, eye closure, jitter, quality factor and transmission distances. It was observed that EDFA provided the consistent good quality of communication for long-distance transmission up to 150 km along with better eye opening and eye closure with acceptable jitter performance. Further, it is observed on the basis of quality factor and bit error rate that EDFA gives comparably better performance than Raman amplifier. Moreover, it is seen that as the data rate of the system increases, the quality of communication signals starts decreasing. [ABSTRACT FROM AUTHOR]