Alireza Nafarieh

A Comparison of Software Defined Network (SDN) Implementation Strategies

Abstract Software defined networking (SDN) is an emerging approach to handle data forwarding and control separately. The notion of programmability has central importance in SDN. Two implementation strategies; proprietary and open source, are shaping the trends of the adoptability of SDN by major hardware manufacturers. A group of leading vendors believes that loose coupling between the logical and physical layers of a network hinders the proper provision of physical resources and suggests a proprietary fix to this problem. The other group regards the notion of openness as s key feature of SDN. This paper compares and contrasts these two implementation strategies of SDN by identifying their respective operating principles, features of the product lines, and weakness and strengths.

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

Abstract Satisfying customers’ traffic engineering connection requests is one of the biggest challenges of todays service providers. However, routing mechanisms which only consider service level specifications as the path selection criteria may not be aware of energy consumption and Co2 emission rate of the routed paths. This can generate huge Co2 emissions and consume energy inefficiently. This paper introduces a hybrid green SLA-based routing approach to lower the Co2 emission rate while it provides the most available routes between any pair of source and destination. A new hybrid path cost function is also proposed in which Co2 emission rate, path length, and path availability are taken into account as the route selection process criteria. As a result of employing the new energy-aware routing algorithm together with the novel path cost function, paths with the minimum Co2 emission and less assigned network resources will be selected while service level agreement requirements are still met.

Personalized Security Approaches in E-banking Employing Flask Architecture over Cloud Environment☆

Abstract Personalized security in E-banking is an important issue for many individuals and companies that are looking for achieving the proper level of security. The cloud environment is a suitable infrastructure to implement personalized security mechanisms for many big companies such as banks. Employing mandatory access controls boosts the security of E-banking to a high level. Flask architecture is the security architecture which enforces mandatory access control that provides a clean separation of security policies and enforcements. In this paper, it a model for implementing personalized security in E-banking over a cloud environment is introduced. Using role-based access control models, the security system can be configured to provide expected level of security in e-payment systems employing user-defined policies for individuals, companies and governmental organizations. The paper focuses on defining such policies and how they improve the level of security.

Dynamically Provisioned Priority-Aware Algorithms in Shared Mesh Optical Networks

The paper introduces two novel algorithms, one each for static and dynamic traffic types, to improve the availability of high priority connection requests over shared mesh optical networks. The proposed algorithms are a complementary study to the previous work. The paper also proposes a new metric, maximum path availability, by which the proposed algorithms improve the performance of high priority requests by reducing blocking probability, increasing availability satisfaction rate, and with better resource utilization using dynamic negotiation of service level agreement parameters between a customer and service providers. In a multi-homed network topology, the introduced algorithms along with the proposed metric can help the customers to modify, refine and further process the final connection requests to better comply with service providers’ network capacity. The simulation results show improvements on preserving the high priority class of traffic for both static and dynamic traffic types compared to other protection schemes in shared mesh optical networks.

A comprehensive analysis of QoS-based routing mechanisms over shared mesh protected optical infrastructures

The paper describes a literature overview of the main building blocks of service level agreement based architectures over priority-aware shared mesh optical networks. The standardized protocols and existing algorithms for path attributes and service level agreement parameters negotiation are studied in this paper and shortcomings of each are identified. A thorough study of the priority-aware, service level agreement based, and risk-aware mechanisms including the existing mechanisms, the advantages and disadvantages, and the remedy for the shortcomings is provided. The mathematical models for availability analysis of different routing mechanisms, protection schemes, and network resources are discussed. Different routing strategies and wavelength assignment approaches are studied as well. The paper tries to show how the quality of service based routing mechanisms can provide service providers better network performance in addition to the higher revenue.

Adaptive Green Routing Mechanism over Optical Networks

This paper is an extension to the previous work that introduced the hybrid energy-aware and service level agreement (SLA) based routing mechanism over optical networks. This paper introduces an adaptive SLA-based routing approach to lower the Co2 emission rate while it provides the most available routes between any pair of source and destination. The paper benefits from the hybrid path cost function presented in the previous work in which Co2 emission rate, path length, and path availability are taken into account as the route selection process criteria. The mechanism proposed in this paper re-routes established optical paths using an adaptive green routing algorithm after the nodes in the network are informed of any changes on the emission factors of the links. As a result of employing the new energy-aware routing algorithm together with the novel path cost function, paths with the minimum Co2 emission and less assigned network resources will be selected. The algorithm presented in this paper keeps Co2 emission at the lowest level with maintaining an adaptive re-routing mechanism over the duration of connections while service level agreement requirements are still met.

Dynamic Inter-domain Negotiation for Green Algorithms in Optical Networks☆

Abstract This paper presents a dynamic inter-domain negotiation mechanism over green optical networks. The proposed propagation mechanism disseminates the source types of energies to all nodes while it advertises a proposed path attribute called minimum path emission. The paper shows how the dynamic negotiation protocol along with the proposed traffic engineering metric improves the performance of green algorithms. This mechanism helps service providers to control the network Co2 emission level in WDM networks and keep the network as green as possible.

The effect of adopting green SLA on key parameters of optical WDM networks

This paper presents green service level agreement (GSLA) awareness for the hybrid and traditional routing mechanisms by proposing a mathematical model for the amount of route greenness, and proposing two algorithms for the adoption of GSLA. The effect of the adoption of GSLA on a network that on average has green energy available for longer duration of a day is modeled by defining a one-step two-by-two Markov matrix and representing the transformation through a state machine. This work also examines a re-provisioning algorithm to deal with the effect of re-provisioning of the established lightpaths in case of a change in the topology of a network. To study the effect of adopting GSLA, two Scenarios with different arrival rates of connections and four performance parameters such as average emission per lambda, average connection length, GSLA satisfaction and success rate are defined and analyzed over NSFnet. Results reveal that adopting the GSLA by routing mechanisms decreases the resource efficiency with both light and heavy traffic in return for less reduction in emission as compared to green and hybrid routing mechanisms.

Analysis on the Effect of Adopting Green SLA on Optical WDM Networks

Abstract This paper analyzes the effect of Green Service Level Agreement (GSLA) on resource efficiency and emission reduction of wavelength-division multiplex (WDM) optical networks governed by Generalized Multi-Protocol Label Switching (GMPLS). Green routing mechanisms may use more resources in serving equal number of connection requests in optical networks, which makes them less favorable for Internet and infrastructure providers. This work shows that the usage of green and hybrid routing mechanism is in fact more resource efficient than using traditional non-green routing methods by simply choosing the greenest route. The amount of greenness of routes in optical networks is requested through GSLA mandating service providers to provide routes for connection requests that are being powered ON by at least certain amount of green energy such as solar energy.

Multi SLA Aware Green Provisioning Mechanism for WDM Networks

Abstract This paper introduces a simple mechanism which attempts to reduce the energy consumption and corresponding Co2 Greenhouse Gas (GHG). This mechanism couples an emission reduction method with multiple service provider Service Level Agreements (SLAs) to ensure an acceptable Service Level Satisfaction (SLS). This purpose is accomplished by formulating and solving a multi-constrained optimization problem. The results show emission reduction with acceptable SLS. This mechanism can be used in different control environments, such as Software Defined Networks (SDN) or Generalized Multi-Protocol Label Switching (GMPLS).