Virtualization and cloud computing are dovetailed. Virtualization is a technique in which a complete installation of one machine is run on another. The result is a system in which all software running on the server is within a virtual machine. Virtualization could be one-to-many or many-to-one. One-to-many enables the users to create many virtualized resources from one physical resource. This approach maximizes the resources utilization. Virtual resources hosting individual applications are mapped to physical resources to provide more efficient server utilization.
Many-to-one virtualization enables the creation of virtual or logical resources from multiple physical resources. This is the core context of cloud computing in which multiple physical resources are grouped together to form one cloud. Virtualization refers to OS virtualization as administrators can implement it by VMware, Xen, or other hypervisor-based technologies. Virtualization is not cloud, rather an enabler for establishing and managing clouds. In the Cisco cloud concept, virtualization is extended to incorporate various types of virtualization, such as network, computer, storage, and services. Generally, there are five varieties of cloud services and four types of deployment approaches, Figure 1.1 illustrates these concepts.
After presenting the cloud computing advantages and disadvantages, it is time to explain more about the cloud computing benefits. There is a difference between advantages and benefits. An advantage is a feature that surpasses the competition, but a benefit is how that feature impacts the users. One of the most key benefits of using cloud computing is that there are several different ways to deploy the cloud infrastructure. Cloud computing is not a one size that fits all affair, for example, the users may have a massive needs to deploy a larger number of servers, or run in house server’s type. Alternatively the users may only need a sip of processing power and consequently are not willing to buy and run a dedicated server. The cloud fits all these needs and there are some factors that control users when thinking about the using cloud, such as:
- Cost/benefit ratio.
- Speed of delivery.
- How much capacity the user will use.
- Whether the data is regulated.
- The organization’s corporate and IT structure.
Cloud computing benefits
- Scalability: The most important characteristic of using cloud computing is the scalability, which allows the user to scale up/down the computing power at any time. If a high demand to use a huge upswing in computing or there is a need for sudden demand on hardware resources, then use rather than buy,
- Simplicity: cloud gives the users an alternative of buying or configuring the hardware or software, so it makes it very simply because the user’s needs from the hardware or the applications will started immediately after requesting it and the cost will be a fraction depend on what their needs,
- Knowledgeable Vendors: The IT world move very fast and every day there a new technology that becomes popular. If the user hosts the application in house, there must be an investment in every update and this will cost much money and efforts. Using the cloud will relief the users from this task while reducing the cost,
- More Internal Resources: Using cloud free IT departments to work on important business related tasks while the service provider will be responsible for critical missions. There is no need to employee more manpower and train them to deal with these low level tasks. Network outages is a nightmare for the IT staff, and
- Security: one of the most important issues in any network is the security and there are many plenty of security risks when using a cloud from service providers, but reputable providers strive to keep their users safe and secure.
The widespread deployment of Web enabled mobile devices made them a target of choice for content creators. Understanding their strengths and their limitations, and using technologies that fit these conditions are keys to create success mobile friendly Web content . The reasons for that include the challenges posed by network costs & delays, memory & Central Processing Unit (CPU) limitations, and keyboard & pointing devices differences. As importantly, mobile devices feature a growing set of advantages with their personal, always available nature, and the increasingly context-aware capabilities.
Wireless Fidelity (Wi-Fi) is now the most mature technology of using wireless for Internet access. Energy limitations of mobile devices are still an issue and to deal with this limitation, the wireless standard 802.11 includes a Power Saving Mode (PSM), but not much attention has been devoted by the research community to understand the performance in depth. PSM is able to save up to 90% of the energy spent when no energy management is used, however PSM is not the optimal solution for energy management. The objective of the 802.11 PSM is to let the wireless interface of a mobile host in the active mode only for the time necessary to exchange data, and turn it off in sleep mode whenever it becomes idle. In a Wi-Fi hotspot, this is achieved by exploiting the central role of the access point. Each mobile host within the hotspot lets the access point know whether it utilizes the PSM or not. Since the access point relays every frame from/to any mobile host, it buffers frames addressed to mobile hosts using the PSM every beacon interval, usually 100 ms, the access point broadcasts a special frame named beacon.
The mobile Web is still evolving and this is an exciting time of early development, but there are still some hurdles that need to be overcome. As seen familiar brands such as Facebook and MySpace porting their presences to the mobile domain, users will see a wider adoption of this channel by the mainstream. When creating content for mobile devices, the designers are usually confronted with numerous development standards and technologies to choose from. In addition, hundreds of different mobile devices with varying functional capabilities, screen resolutions, and sizes are under consideration as well as more than 40 distinct mobile browsers. This lack of uniformity renders testing mobile websites and applications for universal compatibility a near impossibility. Mobile Web developers also brave the high expectations of mobile Web users who anticipate the same caliber experience on their handsets that they enjoy on the desktop Web.
The history of the web and web browser dates back to late 1980s, when a variety of technologies laid the foundation for the first web browser, World Wide Web was founded by Tim Berners-Lee in 1991. That was the starting of a new era the web and web browser brought together a variety of existing and new software and hardware technologies, at the first days browsing the web was text-based user interfaces when the graphic user interface (GUI) become more popular web browsers also move to GUI but all development of them was tend to the desktop users.
When technology grow fast and mobile devices became an important part from our daily life activities, and the need for access web from a mobile increases more and more, here we discover the problem that is the web was not developed for such devices, but there was many trials and contributions to enhance the access from such device, in this thesis we try to add a new contribution through providing some new techniques that try to solve such problem.
The World Wide Web Consortium (W3C) and mobile industry leaders are working together to developing best practices for creating mobile-friendly content and applications, enabling easy access to device descriptions, setting up test suites for increased interoperability of mobile browsers, and exploring ways to use the Web on mobile devices they try also to improve Web content production and access for mobile users and the greater web, The goal is that making Web site access from a mobile device as simple as Web site access from a desktop device, and this is what we called it the web on the move.