What Is Web Hosting Service | Part 6
3. Shared Web Hosting
A shared web hosting is a hosting service that allows a customer more than having your website on the same computer, and using a single web server program. Usually the technique is implemented using virtual hosting, available on most servers.
Shared Web Hosting – Objective
Shared accommodation is made for a computer to serve multiple domains web server. There are several ways to do this, but for virtual hosting you only need to have in memory a copy of the web server and a single network card is sufficient.
A company can do that because it has several similar sites, and wants to share information (for example, that everyone can access the same database). But it can also happen that hosted sites are not related, for example, a small company will be hosting the websites of all its customers on the same computer.
There are two ways to do virtual hosting: name (domain name) and IP (IP address):
By name
Two domains may lead to the same IP (with DNS). So when a visitor enters the IP has to see a page or the other depending on the domain name you typed to enter.
When your web browser connects to the server asking for the page, not only sends the address (URI) you want, but the domain you are accessing through the field Host: HTTP. This is automatic, and HTTP/1.1 is required.
The web server program can read this information and use it to decide which of these domains has to show.
By IP
It is also possible to have the server listen not only to an IP address, but several, and each responds to a different page. For this you can use multiple network cards, but not necessary, since current operating systems allow you to create virtual network interfaces in order to assign multiple IPs to the same card.
Shared Web Hosting – Advantages
- You can use a single computer to serve many domains, rather than having several.
- It takes over your Internet connection.
- Inexpensive and easy to configure.
Shared Web Hosting – Disadvantages
- Share the connection between many domains can cause everyone to go slow.
- There are customers who may refuse to share accommodation. For example, do not want to be on the same computer as the website of the competition and privacy issues and external appearance.
- The virtual hosting does not work with HTTP/0.9 as it does not send the Host field (in HTTP/1.0 is optional, and mandatory in HTTP/1.1.)
- If the DNS is wrong, it is difficult to access the server. You could use the IP to enter (e.g., http://12.34.56.78/) but then the server would not know which domain you want to enter.
4. Cloud Computing / Cloud Hosting
In computing and Information Technology, the term cloud computing is a set of technologies that allow the use of hardware resources (storage, CPU) or distributed software remotely.
Although the term is rather vague and seems to be used in different contexts with different meanings to each other, we can distinguish three basic types of cloud computing:
- SaaS (software as a service) - is the use of programs in remote, often through a web server. This acronym agrees in part the philosophy of a deadline today obsolete, ASP (Application Service Provider).
- PaaS (Platform as a Service) - Similar to SaaS, but is not used in a single program remote but a software platform that can consist of various services, programs, libraries, etc..
- IAAS (Infrastructure as a Service) - Use of hardware resources remotely. This type of cloud is almost a synonym for grid computing, but with an essential feature: the resources are used on demand when a client needs it, not allocated regardless of their actual use.
Data Center
The Data Processing Center (EDC) is the organizational unit that coordinates and maintains the equipment and data management services. Present both within companies of Public Administration, has replaced the office, now past history of computing, known for computing center. Some can actually be called Data Processing Service (SED), especially when the outsourcing agreement.
The EDC shall then:
- Manage and maintain the telematics architecture.
- Acquire, develop and maintain computer equipment and telecommunication facilities, programs, databases, communications, information and anything else in common use.
- Define security policies, defining the limits of resource utilization of EDC and enforce the regulation technique.
- Articulated and * Provide a qualified counseling service.
- To organize courses, seminars and meetings, with the assistance of outside experts also.
The activities of the EDC are:
- Management of operating systems and consulting services for the EDC client-server AIX, UNIX, Linux, Solaris, Windows, Macintosh;
- Management software and server hardware of CED.
- Manage server data acquisition and analysis.
- Manage your home network.
- Care of the following network services: electronic mail, Internet and intranet Web servers, IP and DNS, FTP server, access server, HTTP proxy server, firewall server, network printing and connectivity with local geographical and TCP / IP.
- Monitoring the activities of CED server, network traffic and storage of these data.
- Management of devices: Printers, X-Terminal, Terminal servers, print servers, wireless bridge, scanner and plotter.
- Managing Storage Media and Data Backup servers of CED.
- Manage service calls for action on the corresponding hardware and assistance during the repair.
- Advice Buying computer and data for managing.
- Care of the technical-operating with the sections through the figure of the contact information section.
- Management of call center software.
- Readiness of any agreements with public and private.
C. Utility Computing
Utility computing is defined as the provision of computing resources, such as processing and storage as a metered service similar to traditional public utilities (such as electricity, water, natural gas or telephone).
This system has the advantage of being low or negligible cost to acquire hardware, however, computational resources are essentially rented. Customers who do data processing on a large scale or are against a peak demand can also avoid the delays that would result from physically acquiring and assembling large numbers of computers.
Study: From Wikipedia, the free encyclopedia. The text is available under the Creative Commons.
