With the development of smart grid construction of China Southern Power Grid and the promotion of the integration strategy for power grid companies at all levels, the power grid operation system will ...gradually become standardized, integrated and intelligent. Since the requirements of safety and stabilization for dispatching are growing, the problem of managing multiple power grid operation systems should be solved urgently. However, with complicated structures, POC(Power System Operation Cockpit) is difficult to monitor and control these operation systems. For the reasons above, this thesis presents a remote control technology based on application virtualization. This technology achieves the remote monitoring, controlling and management of various heterogeneous power grid operation systems by building application delivery centres as well as servers and virtualization clients, provided both secure and efficient remote access across applications. It provides technical supports for integrated monitoring and controlling of operation systems.
Today, most large Application Service Providers (ASPs) such as Google, Microsoft, Yahoo, Amazon and Facebook operate multiple geographically distributed datacenters, serving a global user population ...that are often mobile. However, the service-centric deployment and delivery semantics of these modern Internet-scale applications do not fit naturally into the Internet’s host-centric design. In this service-centric model, users connect to a service, and not a particular host. A service virtualizes the application endpoint, and could be replicated, partitioned, distributed and composed over many different hosts in many different locations. To address this gap between design and use, ASPs deploy a service-centric network infrastructure within their enterprise datacenter environments while maintaining a (virtual) host-centric service access interface with the rest-of-the-Internet. This is done using data-plane mechanisms including data-plane proxying (virtualizing the service endpoint) and Layer 7 (L7) traffic steering (dynamically mapping service requests to different application servers and orchestrating service composition and chaining). However, deploying and managing a wide-area distributed infrastructure providing these service-centric mechanisms to support multi-data center environments is prohibitively expensive and difficult even for the largest of ASPs. Therefore, although recent advances in cloud computing make distributed computing resources easily available to smaller ASPs on a very flexible and dynamic pay-as-you-go resource-leasing model, it is difficult for these ASPs to leverage the opportunities provided by such multi-cloud environments without general architectural support for a service-centric Internet. In this paper, we present a new service-centric networking architecture for the current Internet called OpenADN. OpenADN will allow ASPs to be able to fully leverage multi-cloud environments for deploying and delivering their applications over a shared, service-centric, wide-area network infrastructure provided by third-party providers including Internet Service Providers (ISPs), Cloud Service Providers (CSPs) and Content Delivery Networks (CDNs). The OpenADN design leverages the recently proposed framework of Software Defined Networking (SDN) to implement and manage the deployment of OpenADN-aware devices. This paper focuses mostly on the data-plane design of OpenADN.
Edge computing is a powerful tool to face the challenging performance requirements of modern Internet applications. By replicating applications' data and logic across a large number of geographically ...distributed servers, edge computing platforms allow to achieve significant enhancements of the proximity between clients and contents, and of the system scalability. These platforms reveal highly effective when handling requests entailing read-only access to the application data, as these requests can be autonomously served by some edge server typically located closer to the client than the origin site. However, in contexts where end users can trigger transactional manipulations of the application state (e.g., e-Commerce, auctions or financial applications), the corresponding update requests typically need to be redirected to the origin transactional data sources, thus, nullifying any performance benefit arising from data replication and client proximity. To cope with this issue, in this paper, we present a parallel invocation protocol, which exploits the path-diversity along the end-to-end interaction toward the origin sites by concurrently routing transactional requests toward multiple-edge servers. Request processing is finally carried out by a single-edge server, adaptively selected as the most responsive one depending on current system conditions. The proposed edge server selection scheme does not require coordination among (geographically distributed) edge server instances, thus, being very light and scalable. The benefits from our protocol in terms of both reduced and more predictable end-to-end latency are quantified via an extended simulation study.
There are two key issues that prevent Application Service Providers (ASPs) from fully leveraging the cloud "advantage." First, in modern enterprise and Internet-based application environments, a ...separate middlebox infrastructure for providing application delivery services such as security (e.g., firewalls, intrusion detection), performance (e.g., SSL off loaders), and scaling (e.g., load balancers) is deployed. In a cloud datacenter, the ASP does not have any control over the network infrastructure, thus making it hard for them to deploy middleboxes for their cloud-based application deployments. Second, modern services virtualize the application endpoint. A service can no longer be statically mapped to a single end host. Instead, the service is partitioned and replicated across multiple end hosts for better performance and scaling. In enterprise datacenters, service requests are intercepted by an application-level routing service (APR) in the data plane and dynamically mapped to the correct service partition and the best (e.g. least loaded) instance of that partition. However, although multi-cloud (or Inter-cloud) environments allow ASPs to globally distributed their applications over multiple cloud datacenters leased from multiple cloud providers, ASPs need support of a globally distributed APR infrastructure to intelligently route application traffic to the right service instance. But, since such an infrastructure would be extremely hard to own and mange, it is best to design a shared solution where APR could be provided as a service by a third party provider having a globally distributed presence, such as an ISP. Although these requirements seem separate, they can be converged into a single abstraction for supporting application delivery in the cloud context. A sample design of this abstraction is OpenADN, presented here.
With cloud computing, resources such as storage and computation are hosted in a centralized location and made accessible to many users on demand through an internet connection. It is a method of ...accessing a shared pool of computer resources on demand from any locale with little administrative effort. Private and public clouds are now viable options for users and enterprises of all sizes to store and process data (Third-party server). Data access methods are simplified and made more reliable with an internet connection. It may be done anytime and anywhere at a reduced price. When discussing what is meant by "cloud computing," it is important to distinguish between the various service types (SaaS, PaaS, IaaS, SEaaS), features (On-demand service, Broad Network Access, Resource pooling, Rapid Elasticity, Measured Service), and deployment strategies (Public, Private, Community, Hybrid, and Mobile Cloud). The Cloud's flexibility has led to a mass exodus of data. A fundamental challenge for present-day cloud computing storage infrastructures is providing highly secure and efficient data access. Users are drawn to cloud storage for the considerably expanded capacity it provides. Data security must be a top priority. A severe security risk arises when private information is stored off-site outside the user's reach. Due to the vulnerability of data during transmission and storage, data security is crucial. Several different algorithms may be used for cryptography. Data encryption techniques exist, including DES, AES, and Triple DES. In symmetric critical approaches, the key is utilized for both encryption and decryption. In contrast, RSA, ECC, and homomorphic equations are examples of asymmetric cryptosystems, which need two separate keys for encryption and decryption. However, these algorithms can be broken by anybody with enough time and effort. Therefore, it is crucial to improve cloud storage security. This research aims to improve the safety and efficiency of application delivery services hosted on the Cloud.
Nowadays, SMBs (Small to Medium-Sized Business) are booming and competing with, SMEs (Small to Medium-Sized Enterprises) and large enterprises. The evolution of IT and it's need are common to all ...sectors. SMBs IT infrastructre needs a proper website management, scalability, very high reliablity, high performance on par with their counterparts SMEs and large enterpises. So, it's time to provide an imperative service to achieve all these above mentioned requirments in SMBs. Some vendors offer application delivery controllers and server load balancers to achieve these requirements in SMBs. This survey article gives an overview of how application delivery controllers and load balancers helps to achieve the needs of SMBs.
Enterprise networks' firewalls are rarely set up in a shared-protection (N:1) configuration, preferring instead the more costly active-stand by (1+1) configuration. This is due to, in part, to the ...high cost associated with software-based per-flow load balancing at high traffic loads. In this work, we propose the use of SDN/OpenFlow switches as a low-cost hardware-based alternative for subnet-level load balancing, for use in a N:1 firewall array. Our design guarantees that the N:1 system exhibits the same performance of a 1+1 system but at a much lower cost. In particular, the design provides lossless firewall handover of subnets in response to traffic bursts. A prototype of the system has been implemented in Python over the base of the Floodlight OpenFlow Controller and tested in our SDN Test-Bed using the ISPDSL II traffic traces, evaluating the behavior during traffic peaks. Initial results show that the system successfully migrate subnet traffic without packet losses, call blockings, or TCAM exhaustion.
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