GMPLS Networks Research Articles

Protection technique for performance improvement in GMPLS networks

Protection technique for performance improvement in GMPLS networks

Model for Performance Improvement of Blocking Probability in GMPLS Networks

Abstract 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.”

An Improved Particle Swarm Algorithm for Multi-Objectives Based Optimization in MPLS/GMPLS Networks

Particle swarm optimization (PSO) is a swarm-based optimization technique capable of solving different categories of optimization problems. Nevertheless, PSO has a serious exploration issue that makes it a difficult choice for multi-objectives constrained optimization problems (MCOP). At the same time, Multi-Protocol Label Switched (MPLS) and its extended version Generalized MPLS, has become an emerging network technology for modern and diverse applications. Therefore, as per MPLS and Generalized MPLS MCOP needs, it is important to find the Pareto based optimal solutions that guarantee the optimal resource utilization without compromising the quality of services (QoS) within the networks. The paper proposes a novel version of PSO, which includes a modified version of the Elitist learning Strategy (ELS) in PSO that not only solves the existing exploration problem in PSO, but also produces optimal solutions with efficient convergence rates for different MPLS/ GMPLS network scales. The proposed approach has also been applied with two objective functions; the resource provisioning and the traffic load balancing costs. Our simulations and comparative study showed improved results of the proposed algorithm over the well-known optimization algorithms such as standard PSO, Adaptive PSO, Bat and Dolphin algorithm.

MultiSLA-Aware green routing mechanism for GMPLS

In this paper we formulate a MultiSLA-Aware routing mechanism for GMPLS networks. Our approach aims at providing a realistic energy and emission aware routing mechanism by considering multiple Service Level Agreements. The proposed method of this paper has been tested with a more accurate and realistic energy and emission data calculated in course of performing the analysis. Our proposed method shows up to 55% reduction in emission while providing 100% Availability and Delay Service Level Agreement satisfactions.

Maximally node and SRLG-disjoint path pair of min-sum cost in GMPLS networks: a lexicographic approach

Path protection is a fast and capacity-efficient approach for increasing the availability of end-to-end connections. However, sometimes it is not possible to obtain a fully disjoint path pair. In this case, it may be admissible to consider a path pair which is as disjoint as possible, and thus provide the best (in a certain sense) level of the single-fault protection that can be ensured using this type of approach. A shared risk link group (SRLG) is a group of links which have a common risk of failure. Two new heuristics for solving the min-sum maximally node and SRLG-disjoint path pair are presented. The relative performance of the new heuristics and also of two other previously proposed heuristics is evaluated using four different networks. Results, regarding accuracy and execution time of the studied heuristics, show that one of the new proposed algorithms can be a good compromise for use in the Generalized Multi-protocol Label Switching control plane.

A Comparative Study on Emission Efficient Routing Mechanisms in GMPLS Networks

This paper provides a detailed comparison among emission efficient routing mechanisms introduced in previous works. Emission efficient routing mechanisms focus on reducing of the emission of required energy to operate optical networks such as GMPLS networks, by using green sources of energy in systemic and automatic manner without human interaction.

Table Driven Hybrid Energy-aware and SLA-based Routing Mechanism over Optical Networks

This paper introduces an improvement for Hybrid Energy Aware and SLA Based (EASB) routing mechanism enabled for GMPLS networks. The performance of EASB is enhanced significantly by consulting a routing table populated in advance, instead of route calculation for each connection request. The table is “looked up” to determine the route that has the minimum hybrid cost for the given source-destination pair of the connection request. As a result a node with lower compute capability can be used to server the equal amount of connection requests while maintaining emission and resource efficiency.

Performance optimization of GMPLS networks with finite number of sources

The performance of GMPLS network depends upon the various parameters such as number of channels, number of sources, traffic intensity etc. In this paper we have proposed a call blocking model for mode of operation to determine the type of applications suitable for GMPLS networks. Further we have suggested a switch model for GMPLS network and developed a mathematical model for GMPLS network for call blocking probability and call holding probability. In proposed model blocking probability of the network is reduced and then the call blocking performance of the model is compared with the call holding performance.

Selective Aggregated Session Control with QoS Provisioning for GMPLS Networks

Pateikiamas AggSess prieigos kontrolės (PK) algoritmas, skirtas naudoti GMPLS tinkluose. AggSess PK algoritmas testuotas naudojant tinkle modelį, kuriame klasikinis slenkscio PK algoritmas palygintas su AggSess PK implementacija. Nagrinėtos pagrindinės QoS charakteristikos, atvaizduoti eksperimentiniai duomenys ir apibrėžta tolesnių tyrimų tematika. Il. 6, bibl. 7, lent. 2 (anglų kalba; santraukos anglų ir lietuvių k.). DOI: http://dx.doi.org/10.5755/j01.eee.122.6.1824

QoS provisioning by novel parallel LSP based routing/signaling protocol in GMPLS network

In this paper, we have developed the new algorithm based on parallel Label Switched Path (LSP) generation using a quantized threshold for reducing the blocking probability by efficiently using the available WDM network resources on the basis of weighted routing/signaling. We suggested three different models with various levels of wavelength conversion at IP/MPLS router for implementing the algorithm. We proposed the measure of reservation factors for the quantized parallel λLSP for each model. The reservation factor ratio comparative graph shows the effectiveness of the algorithm. Further the QoS routing for the purposed algorithm by measuring blocking probability of each model and the effect of o-e-o conversion is investigated against the fixed model. The improvement has been shown over the existing models.

Performance of label switched path dynamic provisioning in GMPLS networks

Given the fact that control channels in GMPLS/MPLS-TE networks use packet-based forwarding, and the processing of control messages may be subject to various factors, the provisioning delay of an LSP could be highly random. To bridge the gap between the variable performance and demanding application needs, it is imperative to measure and characterize the LSP provisioning performance. In this article, we introduce the ongoing activities in IETF on defining standardized metrics and measurement methodologies for GMPLS/MPLS-TE performance. We also present our experiences in testing a number of GMPLS networks. The results can be seen as a sketch of performances of current state-of-the-art GMPLS implementations. We further point out possible future work in this area.

FWM Constraints Management for Lightpath Establishment in GMPLS Networks

In all-optical networks, management of physical layer restrictions should collaborate in lightpath establishment. Label-Switched Path validation in Generalized MultiProtocol Label Switching on Dense Wavelength Division Multiplexing network requires the treatment of the physical impairment-related parameters along the provisioned route.

Optical Plug and Play Technique for Automatic GMPLS Network Construction

We propose a mechanism called “optical plug and play” for constructing GMPLS networks automatically. It offers lower operation effort and fast network construction, and avoids misconfiguration. Optical plug and play architecture has its procedure, a link-up search mechanism for OXCs, network and node architectures to realize optical plug and play, and an LMP extension to exchange the information between nodes necessary for identifying adjacent nodes. We implement prototypes of both OXCs and routers that support the optical plug and play proposal. Simulations and experiments confirm its performance and feasibility.

GMPLS Control Plane Network Design With Resilience Guarantees

A one-to-one association between data and control channels has traditionally existed in transport networks. Being the control plane embedded in the data plane, the design of the former, as well as its resilience, has been addressed in the latter's one. However, a main GMPLS architectural requirement is to provide a clean separation between control and data planes. In this sense, the control plane in GMPLS networks may describe a different topology than the data plane, even realized over a separated IP network. As a consequence of this, data and control network design become no more linked in such scenarios. To the best of our knowledge, no works in the literature have addressed an independent design of the control plane in GMPLS-enabled networks regardless of the data plane. In this paper, we provide a method to obtain the optimal GMPLS control plane design, minimizing the network Capital Expenditures (CAPEX) while matching specific resilience requirements. To this goal, the problem of finding an optimal control plane topology that ensures a certain resilience level is formulated as a non-linear combinatorial model. This model, however, does not scale properly for large backbone networks. In view of this, a constructive linear method is also presented and its optimality validated through simulations on several reference network scenarios. Furthermore, its benefits in terms of total execution time are also highlighted.

MPLS automatic bandwidth allocation via adaptive hysteresis

MPLS automatic bandwidth allocation (or provisioning) refers to the process of dynamically updating the bandwidth allocation of a label switched path on the basis of actual aggregate traffic demand on this path. Since bandwidth updates require signaling, it is common to limit the rate of updates to reduce signaling costs. In this article, we propose a model-free asynchronous adaptive hysteresis algorithm for MPLS automatic bandwidth allocation under bandwidth update rate constraints. We validate the effectiveness of the proposed approach by comparing it against existing schemes in (i) voice and (ii) data traffic scenarios. The proposed method can also be used in more general GMPLS networks.

Fuzzy-CAC for LSP Setup in GMPLS Networks

In this investigation the new Fuzzy-CAC algorithm is proposed for RSVP-TE protocol development for use in GMPLS networks. The Fuzzy-CAC algorithm is based on expert knowledge IF-THEN rule collection. Decision making is flexible, due to the contemporaneous analysis of input variables and lack of crisp valued inputs. Classical threshold CAC algorithm is compared to the Fuzzy algorithm implementation, main characteristics are analyzed. Experimental data are depicted and future research subjects are described.

Restoration in multi-domain GMPLS-based networks

In this paper, we evaluate the efficiency of using restoration mechanisms in a dynamic multi-domain GMPLS network. Major challenges and solutions are introduced and two well-known restoration schemes (End-to-End and Local-to-End) are evaluated. Additionally, new restoration mechanisms are introduced: one based on the position of a failed link, called Location-Based, and another based on minimizing the additional resources consumed during restoration, called Shortest-New. A complete set of simulations in different network scenarios show where each mechanism is more efficient in terms, such as, resource overbuild or recovery delay.

Improving the Resilience of Emerging Generation GMPLS Networks

We propose a traffic engineering (TE) scheme that uses virtual preemption and configurable survivability to improve the resilience of the emerging-generation GMPLS networks. Virtual preemption ranks the rerouting requests based on bandwidth granularity and, using this ranking, reroutes these requests to allow the highest-bandwidth-demanding requests to be rerouted first with the expectation of achieving higher restorability. Configurable survivability moves the network operating conditions close to a predefined performance pattern and balances the routing configuration to improve the network survivability. Simulation reveals that the proposed TE scheme can increase the survivability of a network and achieve higher restorability while maintaining the signaling efficiency at an acceptable level.

Label Preference Schemes for Lightpath Provisioning and Restoration in Distributed GMPLS Networks

In wavelength-routed networks based on a GMPLS control plane, the resource reservation protocol with traffic engineering extensions (RSVP-TE) allows to establish end-to-end lightpaths. The resource reservation can be blocked due to lack of available resources (forward blocking) or due to resource contentions (backward blocking). In wavelength-routed networks, the backward blocking is the predominant blocking contribution, when traffic load is low or highly-dynamic and when lightpath restoration takes place. To reduce the backward blocking, the paper proposes two label preference (LP) schemes compliant with RSVP-TE message exchanges. LP schemes provide the destination node with a label identifying the preferred wavelength to reserve. The preferred label is computed in a distributed way during the forward signaling phase, with the objective of assigning disjoint wavelengths to reservation attempts that may contend the resources. Simulation results demonstrate that, compared to other schemes, LP schemes are effective in reducing the backward blocking during both lightpath provisioning and restoration, without negatively impacting the forward blocking.

A multi-area MPLS/GMPLS interoperability trial over ROADM/OXC network

This article describes the first multi-area multiprotocol label switching and generalized MPLS interoperability trial over a reconfigurable optical add/drop multiplexer and optical cross-connect network. The interoperability trial demonstrated the routing of label switched paths over a multi-area GMPLS controlled ROADM/OXC network and the control of Ethernet over MPLS transport service on top of the GMPLS network. The trial was conducted using various network elements provided by 14 institutions and was carried out in Tokyo and Virginia. This article introduces the motivation for the trial, technical issues related to controlling multiarea MPLS/GMPLS networks, test network topology, and experimental results. The results show that the interior gateway routing protocolbased multi-area routing architecture is a promising solution for the nationwide deployment of GMPLS networks within a carrier domain. In addition, this article discusses the technical issues of routing constraints in ROADM/OXC networks and the limit of multiarea routing without the Path Computation Element Protocol.