In Feburary 2016 29,
Web projects can store data in many different ways. Effective website projects can therefore involve developing data driven websites and Web applications. Web databases include MySQL and Oracle, both of which developers can create and query using SQL. To build a Web project with a Web database, learners can use server side programming in PHP or ASP, or optionally Java. Many websites now store data in XML format, so Web projects in which learners model and implement XML data structures may also be useful.
Commerce
Anyone working as a Web developer will often work on commercial websites. These vary from simple technologies using automated payment methods such as PayPal, to complex bespoke systems designed using database systems. Any Web project involving secure processing of payments is a good way to familiarize learners with the basic principles in e-commerce development projects. Such projects can optionally include websites with user accounts and registration.
Interactivity
At client side, Web development can involve intense amounts of JavaScript processing to achieve a deep level of interactivity for users. Any Web development project with significant requirements in terms of interactivity may therefore be valuable. As well as implementing website functions manually, developers can learn to use external JavaScript functionality made available through resources such as the jQuery library and associated tools. Working with a third-party interface like this is another common activity for professional developers.
Multimedia
Websites use many different media types. Creating items of the various media formats available is one possible element in a development project. The other aspect of this is learning how best to deploy multimedia items within websites in ways that will make the media content as widely accessible as possible, to users browsing in unpredictable contexts. Tools and technologies involved in multimedia Web development include Adobe Creative Suite and HTML5.
Content Management
Rather than creating a bespoke database and user management system for every client, many Web developers use CMS (Content Management Systems) solutions. Popular CMS options include Joomla, WordPress and Drupal, so using any one of these within a development project should equip learners with the general principles and practices. When a CMS is deployed on a website, it facilitates creation, editing and maintenance of website content. Developers using CMS solutions often need to tailor these to suit the client, including making alterations to both the HTML markup and CSS (Cascading Style Sheet) declarations.
In Feburary 2016 29,
Showing posts with label systems. Show all posts
Showing posts with label systems. Show all posts
Monday, 29 February 2016
Monday, 22 February 2016
The Advantages of ProtocolsIn Feburary 2016 22,
In Feburary 2016 22,
Transfer protocols move files and data from one location to another. Two computers in the operation are required: one is a transferring server and the other a receiving client. Several file transfer protocols include the following:FTP (file transfer protocol) allows the transfer of files. It establishes a connection to a remote client and transfers the files until completed, and then it disconnects. The connection can be in an internal network or over the Internet. Developed in 1971, this protocol served as one of the objectives for the development of the Internet.Xmodem is an alternative to the FTP protocol. It was popular with bulletin board services in the late 1970s because of its simplicity and ease of use.Kermit is a binary (0's and 1's) and text file transfer protocol designed in the early 1980s. For the transfer to occur a file conversion takes place to binary format before transmittal and then converted back afterwards. This allowed for file transfers over dissimilar systems.The advantage of these file transfer protocols is that they share information between different computer systems and different formats.
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Transfer protocols allow files and data to move across networks.
E-mail Protocols
The Internet Message Access Protocol (IMAP) allows an e-mail client to access e-mail messages on a remote e-mail server.IMAP supports two modes of operation: online and offline. In online mode, e-mail clients using IMAP leave the e-mail messages on the server until the user purposely deletes them. In offline mode, the e-mail is downloaded and then deleted. This characteristic of the IMAP operation allows multiple clients to manage the same mailbox. The upshot is that the mail stays on the server automatically until deleted.POP (Post Office Protocol) is an alternate e-mail protocol that supports simple download and delete for access to remote mailboxes. Most POP clients have an option to leave e-mail on the server after download. However, e-mail clients typically follow this procedure. They connect to the server, retrieve their messages, store them on the user's local PC and then delete them from the server and disconnect. The upshot is, the mail is automatically deleted unless kept.The advantage of both of these protocols is enhanced e-mail management.
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E-mail protocols allow personal information to go to other individuals.
Software Developer Protocols
Software developers use protocols in their work. Platform-based database protocols like JDBC (Java DataBase Connectivity) or ADO (active x database objects) have a performance advantage. Also, flexibility and reuse are two main advantages of using a neutral platform protocol such as SOAP (Simple Object Access Protocol).This is a protocol specification that facilitates the exchange of structured information in web services.By using protocols, software architects and program developers can determine the opportunity cost of the project, that is, whether the development is going to be faster versus whether the program is going to be faster. These performance versus flexibility alternatives affect the coding decision, which impacts the way the program will run.The advantage of using these protocols is that they improve the performance of programs and provide flexibility in program design.
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Software that uses protocols can perform faster and is more flexible.
In Feburary 2016 22,
Transfer protocols move files and data from one location to another. Two computers in the operation are required: one is a transferring server and the other a receiving client. Several file transfer protocols include the following:FTP (file transfer protocol) allows the transfer of files. It establishes a connection to a remote client and transfers the files until completed, and then it disconnects. The connection can be in an internal network or over the Internet. Developed in 1971, this protocol served as one of the objectives for the development of the Internet.Xmodem is an alternative to the FTP protocol. It was popular with bulletin board services in the late 1970s because of its simplicity and ease of use.Kermit is a binary (0's and 1's) and text file transfer protocol designed in the early 1980s. For the transfer to occur a file conversion takes place to binary format before transmittal and then converted back afterwards. This allowed for file transfers over dissimilar systems.The advantage of these file transfer protocols is that they share information between different computer systems and different formats.
Fotolia.com'>
Transfer protocols allow files and data to move across networks.
E-mail Protocols
The Internet Message Access Protocol (IMAP) allows an e-mail client to access e-mail messages on a remote e-mail server.IMAP supports two modes of operation: online and offline. In online mode, e-mail clients using IMAP leave the e-mail messages on the server until the user purposely deletes them. In offline mode, the e-mail is downloaded and then deleted. This characteristic of the IMAP operation allows multiple clients to manage the same mailbox. The upshot is that the mail stays on the server automatically until deleted.POP (Post Office Protocol) is an alternate e-mail protocol that supports simple download and delete for access to remote mailboxes. Most POP clients have an option to leave e-mail on the server after download. However, e-mail clients typically follow this procedure. They connect to the server, retrieve their messages, store them on the user's local PC and then delete them from the server and disconnect. The upshot is, the mail is automatically deleted unless kept.The advantage of both of these protocols is enhanced e-mail management.
Fotolia.com'>
E-mail protocols allow personal information to go to other individuals.
Software Developer Protocols
Software developers use protocols in their work. Platform-based database protocols like JDBC (Java DataBase Connectivity) or ADO (active x database objects) have a performance advantage. Also, flexibility and reuse are two main advantages of using a neutral platform protocol such as SOAP (Simple Object Access Protocol).This is a protocol specification that facilitates the exchange of structured information in web services.By using protocols, software architects and program developers can determine the opportunity cost of the project, that is, whether the development is going to be faster versus whether the program is going to be faster. These performance versus flexibility alternatives affect the coding decision, which impacts the way the program will run.The advantage of using these protocols is that they improve the performance of programs and provide flexibility in program design.
Fotolia.com'>
Software that uses protocols can perform faster and is more flexible.
In Feburary 2016 22,
Friday, 19 February 2016
How to Set Up a CentOS Email ServerIn Feburary 2016 19,
In Feburary 2016 19,
Open a terminal by clicking 'Applications,' 'Accessories,' and 'Terminal.'
Type 'sudo yum install postfix.i386.' Give the root password if asked and answer 'yes' to any questions. PostFix is used to send and receive email from the Internet. Type 'sudo yum install dovecot.' Again, give the root password and answer yes to any questions you are asked by the installer. Dovecot will provide users with IMAP or POP3 access to their email accounts.
Edit the configuration file for Postfix. Type 'sudo nano /etc/postfix/main.cf' to open the configuration file in the Nano text editor. The defaults will work well for most systems, but a more sophisticated mail server will require you to specify some of the options in the configuration file. The most important setting is 'home_mailbox.' This will be each user's mailbox directory in their homepage. If you wish to use the Maildir format, the directory should end with a trailing forward slash, like this:home_mailbox = mail/Another option is the mbox format, and to use this format, simply leave off the trailing forward slash: home_mailbox = mailBoth formats are powerful, however there are subtle and complex differences between them. Whichever you choose to use, remember that choice. Find the 'myhostname' and 'mydomain' settings and give them the domain name you have associated with your computer. For example, if you own the domain name 'happy.com,' the options should read:myhostname=mail.happy.com
mydomain=happy.comYou can exit nano by hitting Ctrl-O (to save) and Ctrl-X (to exit.)
Edit the configuration file for Dovecot. Type 'sudo nano /etc/dovecot.conf.' The most important option is protocols. Ensure that this includes the protocol you wish your email users to use. The most popular options are 'imap' and 'pop3,' and you can enable secure connections by appending an 's' to each option.
Set the mail location to the same directory you chose in Step 3. Precede it with the format you choose in step 3. For example:mail_location = maildir:~/mailormail_location = mbox:~/mailFinally, if you use a 64-bit version of CentOS, change the 'login_process_size' to '64.'
Create a user mailbox. Type the following:mkdir /home/bill/mail
chown bill:bill /home/bill/mail
chmod -R 700 /home/john/mailThis creates the mail directory, ensures that the user owns his mail directory, and allows him to access it. This must be repeated for each user who has an email account. In this example, 'bill' has the email account 'bill@happy.com.'
Start the server. Type this code in the terminal:chkconfig --level 345 dovecot on
/etc/init.d/dovecot start
/etc/init.d/postfix start
In Feburary 2016 19,
Open a terminal by clicking 'Applications,' 'Accessories,' and 'Terminal.'
Type 'sudo yum install postfix.i386.' Give the root password if asked and answer 'yes' to any questions. PostFix is used to send and receive email from the Internet. Type 'sudo yum install dovecot.' Again, give the root password and answer yes to any questions you are asked by the installer. Dovecot will provide users with IMAP or POP3 access to their email accounts.
Edit the configuration file for Postfix. Type 'sudo nano /etc/postfix/main.cf' to open the configuration file in the Nano text editor. The defaults will work well for most systems, but a more sophisticated mail server will require you to specify some of the options in the configuration file. The most important setting is 'home_mailbox.' This will be each user's mailbox directory in their homepage. If you wish to use the Maildir format, the directory should end with a trailing forward slash, like this:home_mailbox = mail/Another option is the mbox format, and to use this format, simply leave off the trailing forward slash: home_mailbox = mailBoth formats are powerful, however there are subtle and complex differences between them. Whichever you choose to use, remember that choice. Find the 'myhostname' and 'mydomain' settings and give them the domain name you have associated with your computer. For example, if you own the domain name 'happy.com,' the options should read:myhostname=mail.happy.com
mydomain=happy.comYou can exit nano by hitting Ctrl-O (to save) and Ctrl-X (to exit.)
Edit the configuration file for Dovecot. Type 'sudo nano /etc/dovecot.conf.' The most important option is protocols. Ensure that this includes the protocol you wish your email users to use. The most popular options are 'imap' and 'pop3,' and you can enable secure connections by appending an 's' to each option.
Set the mail location to the same directory you chose in Step 3. Precede it with the format you choose in step 3. For example:mail_location = maildir:~/mailormail_location = mbox:~/mailFinally, if you use a 64-bit version of CentOS, change the 'login_process_size' to '64.'
Create a user mailbox. Type the following:mkdir /home/bill/mail
chown bill:bill /home/bill/mail
chmod -R 700 /home/john/mailThis creates the mail directory, ensures that the user owns his mail directory, and allows him to access it. This must be repeated for each user who has an email account. In this example, 'bill' has the email account 'bill@happy.com.'
Start the server. Type this code in the terminal:chkconfig --level 345 dovecot on
/etc/init.d/dovecot start
/etc/init.d/postfix start
In Feburary 2016 19,
Friday, 12 February 2016
What Is an FTP Server?In Feburary 2016 12,
In Feburary 2016 12,
The first published standard for the File Transfer Protocol predates the Transmission Control Protocol and Internet Protocol (TCP/IP) in use today. Published in 1971, FTP ran over the Network Control Protocol (NCP), the Internet's predecessor. It was designed to facilitate indirect exchanges across the network--those exchanges in which data or programs were transmitted to a different system to be executed or worked on.
Uses
FTP was originally designed for large bulk transfers of data, so it's ideally suited for file downloads. This is particularly true across the Internet, where FTP is used commonly as the mechanism for downloading patches, songs and purchased programs.
Function
At a technical level, FTP uses an out-of-band control mechanism. This means the data moves between client and server using one communication path. Control messages that govern the flow of that data move between the systems on a different communication channel. Because FTP was designed for file transfers, it leverages the TCP as an underlying protocol, which includes more robust packet delivery assurance.
Identification
Much like most other client/server relationships, the FTP client is the system that makes a request for data, and the FTP server provides that data. It is a common Internet practice to reserve a specific machine or even a set (or 'farm') of machines to function as FTP servers for an enterprise. Their purpose is to listen for client requests and (assuming security checks allow for it) quickly and accurately transmit large files to those clients. If your web browser suddenly reads 'ftp://
' you'll know you're leveraging the FTP protocol in your download.
Benefits
Web pages, which commonly download through the HyperText Transfer Protocol (HTTP), are usually comprised of many small files that must be simultaneously downloaded to a wide variety of clients in small degrees. Any given web page may make dozens or even hundreds of information requests just to populate a single page. This is a fundamentally different style of work than one request that results in several dozen megabytes of continuous data download. It is precisely because of this difference that FTP servers have continued to have their place amid the many web servers on the Internet.
Design
Because FTP servers are designed for large file transfers, they are best used as a part of an overall Internet server strategy. It's common, for instance, to have general informational pages hosted by web (HTTP) servers and include links in these pages to separate servers used to host large files for download--such as music, videos, large PDF documents, computer code and patches. Because security can be an issue with FTP (originally designed to send usernames and passwords in clear text), it is typical to see FTP servers host files that do not require specific permission for download--or to use a federated security model that leaves authentication and authorization to other systems.
In Feburary 2016 12,
The first published standard for the File Transfer Protocol predates the Transmission Control Protocol and Internet Protocol (TCP/IP) in use today. Published in 1971, FTP ran over the Network Control Protocol (NCP), the Internet's predecessor. It was designed to facilitate indirect exchanges across the network--those exchanges in which data or programs were transmitted to a different system to be executed or worked on.
Uses
FTP was originally designed for large bulk transfers of data, so it's ideally suited for file downloads. This is particularly true across the Internet, where FTP is used commonly as the mechanism for downloading patches, songs and purchased programs.
Function
At a technical level, FTP uses an out-of-band control mechanism. This means the data moves between client and server using one communication path. Control messages that govern the flow of that data move between the systems on a different communication channel. Because FTP was designed for file transfers, it leverages the TCP as an underlying protocol, which includes more robust packet delivery assurance.
Identification
Much like most other client/server relationships, the FTP client is the system that makes a request for data, and the FTP server provides that data. It is a common Internet practice to reserve a specific machine or even a set (or 'farm') of machines to function as FTP servers for an enterprise. Their purpose is to listen for client requests and (assuming security checks allow for it) quickly and accurately transmit large files to those clients. If your web browser suddenly reads 'ftp://
' you'll know you're leveraging the FTP protocol in your download.
Benefits
Web pages, which commonly download through the HyperText Transfer Protocol (HTTP), are usually comprised of many small files that must be simultaneously downloaded to a wide variety of clients in small degrees. Any given web page may make dozens or even hundreds of information requests just to populate a single page. This is a fundamentally different style of work than one request that results in several dozen megabytes of continuous data download. It is precisely because of this difference that FTP servers have continued to have their place amid the many web servers on the Internet.
Design
Because FTP servers are designed for large file transfers, they are best used as a part of an overall Internet server strategy. It's common, for instance, to have general informational pages hosted by web (HTTP) servers and include links in these pages to separate servers used to host large files for download--such as music, videos, large PDF documents, computer code and patches. Because security can be an issue with FTP (originally designed to send usernames and passwords in clear text), it is typical to see FTP servers host files that do not require specific permission for download--or to use a federated security model that leaves authentication and authorization to other systems.
In Feburary 2016 12,
Thursday, 11 February 2016
The Advantages of Java AppletsIn Feburary 2016 11,
In Feburary 2016 11,
Java applets have increased interactivity for users. This is possible because the applets are actually software programs that are being ran from a browser. This means that the designer has an array of programs that can be created and turned into online applications. Increased interactivity is commonly found in the form of a game or a visual presentation.
Cross Platform Ability
Java is designed to be cross-platform compatible, meaning the same program can be used on multiple operating systems. Programmers do not have to design separate applications for separate operating systems; allowing their program to be used by nearly anyone using a web browser. This also permits applets to run on certain mobile phones.
Safety
Before downloading and running on your computer, Java applets must have the user's approval. This protects your computer by not allowing unwanted applets to download. Java also has built-in security that protects applets from doing anything harmful to your computer. A Java applet must also go through a verification process as it downloads to ensure the applet does not violate any access restrictions.
Server and Client Communication
Unlike most web programming languages, Java allows for dynamic server and client communication. This means that once the applet loads, it can consistently transfer information to and from the server. The constant line of communication can allow Java to update information in the applet as the program runs.
Database Integration
Java makes it easy to integrate the use of a database in an applet. This is mostly due to the ability for communication with the server. Java also has built-in functions for communicating with popular databases such as SQL, MySQL and Oracle.
In Feburary 2016 11,
Java applets have increased interactivity for users. This is possible because the applets are actually software programs that are being ran from a browser. This means that the designer has an array of programs that can be created and turned into online applications. Increased interactivity is commonly found in the form of a game or a visual presentation.
Cross Platform Ability
Java is designed to be cross-platform compatible, meaning the same program can be used on multiple operating systems. Programmers do not have to design separate applications for separate operating systems; allowing their program to be used by nearly anyone using a web browser. This also permits applets to run on certain mobile phones.
Safety
Before downloading and running on your computer, Java applets must have the user's approval. This protects your computer by not allowing unwanted applets to download. Java also has built-in security that protects applets from doing anything harmful to your computer. A Java applet must also go through a verification process as it downloads to ensure the applet does not violate any access restrictions.
Server and Client Communication
Unlike most web programming languages, Java allows for dynamic server and client communication. This means that once the applet loads, it can consistently transfer information to and from the server. The constant line of communication can allow Java to update information in the applet as the program runs.
Database Integration
Java makes it easy to integrate the use of a database in an applet. This is mostly due to the ability for communication with the server. Java also has built-in functions for communicating with popular databases such as SQL, MySQL and Oracle.
In Feburary 2016 11,
Tuesday, 9 February 2016
The Differences Between a Business Analyst a Data AnalystIn Feburary 2016 09,
In Feburary 2016 09,
A business analyst's understanding of an organization's operating and technological environments enables him to serve as an intermediary between the organization's user community and its information technology staff. The analyst documents a planned system's functional requirements, creates a business case that supports the IT project, conveys the requirements to the information technology staff, and confirms by a review of system project documentation that approved and documented business requirements are correctly represented in a system project plan. In addition, the analyst confirms through system testing that a developed or revised system meets the functional, performance and security requirements that are defined for the system.
Data Analyst
The focus of a data analyst is the collection, organization and analysis of data. Data management and reporting systems are used by the analyst to collect and organize data that may be extracted from multiple databases. In addition, the analyst determines the data collection protocols to be used that will best support the subsequent extrapolation and interpolation of values required to meet business objectives. The data analyst selects the reporting tools required to create graphs, charts and other report formats necessary to support the user community. Analysts also possess the technical expertise required to troubleshoot data extraction and data storage issues.
Data Analyst Expertise
The data analyst skill set includes mathematical skills as well as experience with the use of reporting tools including Microsoft Access, Excel and Crystal Reports. Expertise with relational database design and development tools including MySQL and SQL Server is also useful. Frequently, data analysts have earned a four-year statistics, computer science or business administration degree.
Business Analyst Expertise
The skills of a business analyst may include expertise in the implementation of particular software such as SAP or PeopleSoft applications, in addition to experience working with data extraction and testing tools. Educational credentials frequently include a business degree. An MBA is not unusual. Analysts' work experience may be focused in a particular industry in that many business processes are industry specific. Professional experience that reflects support of change management, customer service and supply chain initiatives is also common.
In Feburary 2016 09,
A business analyst's understanding of an organization's operating and technological environments enables him to serve as an intermediary between the organization's user community and its information technology staff. The analyst documents a planned system's functional requirements, creates a business case that supports the IT project, conveys the requirements to the information technology staff, and confirms by a review of system project documentation that approved and documented business requirements are correctly represented in a system project plan. In addition, the analyst confirms through system testing that a developed or revised system meets the functional, performance and security requirements that are defined for the system.
Data Analyst
The focus of a data analyst is the collection, organization and analysis of data. Data management and reporting systems are used by the analyst to collect and organize data that may be extracted from multiple databases. In addition, the analyst determines the data collection protocols to be used that will best support the subsequent extrapolation and interpolation of values required to meet business objectives. The data analyst selects the reporting tools required to create graphs, charts and other report formats necessary to support the user community. Analysts also possess the technical expertise required to troubleshoot data extraction and data storage issues.
Data Analyst Expertise
The data analyst skill set includes mathematical skills as well as experience with the use of reporting tools including Microsoft Access, Excel and Crystal Reports. Expertise with relational database design and development tools including MySQL and SQL Server is also useful. Frequently, data analysts have earned a four-year statistics, computer science or business administration degree.
Business Analyst Expertise
The skills of a business analyst may include expertise in the implementation of particular software such as SAP or PeopleSoft applications, in addition to experience working with data extraction and testing tools. Educational credentials frequently include a business degree. An MBA is not unusual. Analysts' work experience may be focused in a particular industry in that many business processes are industry specific. Professional experience that reflects support of change management, customer service and supply chain initiatives is also common.
In Feburary 2016 09,
Monday, 8 February 2016
How to Set Up a Proxy ServerIn Feburary 2016 08,
In Feburary 2016 08,
Set up WinProxy. WinProxy is widely used for windows-based servers which also provides Network Address Translation (NAT) and also supports HTTP, Real Audio, Real Video, FTP, Telnet, Secure Sockets and DNS. The system is popularity because it doesn't need to have any software loaded on the client's end, thereby saving time and effort.
Ensure that all the systems, including the client's systems, have been configured with TCP/IP (Transmission Control Protocol/Internet Protocol). TCP/IP is the basic communication language or protocol used by Internet, as well as private networks, to access the intranet (internal sites) or extranet (external sites).
Run the installation wizard for the WinProxy. You would need to initially enter the product key on the initial screen to register the product.
Select the type of Internet connection and choose the name of your connection.
Enter the user name and password of your Internet connection.
Let the automactic configuration scripts of the WinProxy run. This allows WinProxy to assign IP (Internet Protocol) addresses automatically to each device within the LAN (Local Area Network), meaning the internal connections. Each IP is unique on each device.
Follow the prompt to disconnect from your network, if you are already connected. WinProxy will then go through the verifications of each operation.
Verify if your proxy server works by having a tester or client computer test the system. The person should be allowed to get through the selected sites. Also, the proxy server should be able to check the URL (Uniform Resource Locator) of outgoing requests made for Web pages. This is done by inspecting HTTP GET and POST messages. Lastly, the system should also be able to see incoming data traffic, including filtering content of incoming messages.
In Feburary 2016 08,
Set up WinProxy. WinProxy is widely used for windows-based servers which also provides Network Address Translation (NAT) and also supports HTTP, Real Audio, Real Video, FTP, Telnet, Secure Sockets and DNS. The system is popularity because it doesn't need to have any software loaded on the client's end, thereby saving time and effort.
Ensure that all the systems, including the client's systems, have been configured with TCP/IP (Transmission Control Protocol/Internet Protocol). TCP/IP is the basic communication language or protocol used by Internet, as well as private networks, to access the intranet (internal sites) or extranet (external sites).
Run the installation wizard for the WinProxy. You would need to initially enter the product key on the initial screen to register the product.
Select the type of Internet connection and choose the name of your connection.
Enter the user name and password of your Internet connection.
Let the automactic configuration scripts of the WinProxy run. This allows WinProxy to assign IP (Internet Protocol) addresses automatically to each device within the LAN (Local Area Network), meaning the internal connections. Each IP is unique on each device.
Follow the prompt to disconnect from your network, if you are already connected. WinProxy will then go through the verifications of each operation.
Verify if your proxy server works by having a tester or client computer test the system. The person should be allowed to get through the selected sites. Also, the proxy server should be able to check the URL (Uniform Resource Locator) of outgoing requests made for Web pages. This is done by inspecting HTTP GET and POST messages. Lastly, the system should also be able to see incoming data traffic, including filtering content of incoming messages.
In Feburary 2016 08,
Saturday, 6 February 2016
How Does a Server Work?In Feburary 2016 06,
In Feburary 2016 06,
The basic function of a server is to listen in on a port for incoming network requests, and a good demonstration of this is the interaction between a Web server and browser. Although to a user the process is instantaneous, or nearly so, when he clicks a link while surfing the Web, several things are taking place behind the scenes: the request for the Web page is transmitted to the corresponding Web server, the server fetches and assembles the Web page and retransmits it using a protocol like HTTP, and, finally, the user's browser receives the data, converts it, and displays the page to him.
Understanding the Technology
Depending on the type of server being set up, a server-class machine with specialized hardware is usually needed. Rather than a hard drive like most desktops have, servers use a data storage system known as Redundant Array of Inexpensive Disks, or RAID for short. As the name implies, RAID systems are actually several disk drives configured to act like one. This improves efficiency, and if one disk fails, the array continues to function with little or no loss of data. Commercial servers also need fast processors, enough RAM to service the estimated number of requests, and an uninterrupted power supply. Many organizations have redundancies built into their system to accommodate failover; that is, if one server goes down, the standby server takes over immediately.
Types of Servers
Some of the most common servers in use today are database servers, application servers, mail servers and Web servers. As the name indicates, a database server provides the services and connections for storing, organizing and searching enterprise data. An application server, also called middleware, is the glue that holds the entire system together; it provides the runtime environment for applications and seamlessly coordinates things between the applications and database. Without mail servers, email would not get delivered; as bad or worse to go down would be Web servers, which are what allow people to surf the Web. Other types of critical servers in use are FTP servers, print servers, proxy servers, file servers and domain-name servers, to name a few.
Setting Up a Server
Almost any computer can be set up as a server. Many people use slightly obsolete computers to set up their own network servers at home using operating systems like Linux that aren't resource-intensive -- some don't even have graphical user interfaces -- and know that you don't need newer machines to make good servers. Some folks even set up Web servers and use it to host their own site, and the remarkable thing is that this can be done on a shoestring budget given that most of the software you will need is open source and free. Also, unless you're planning on having Web traffic approaching that of Amazon or Google, an old computer should be powerful enough for your server needs. There are some good, easy to understand tutorials on the Web to help you get started (see links in Resources).
In Feburary 2016 06,
The basic function of a server is to listen in on a port for incoming network requests, and a good demonstration of this is the interaction between a Web server and browser. Although to a user the process is instantaneous, or nearly so, when he clicks a link while surfing the Web, several things are taking place behind the scenes: the request for the Web page is transmitted to the corresponding Web server, the server fetches and assembles the Web page and retransmits it using a protocol like HTTP, and, finally, the user's browser receives the data, converts it, and displays the page to him.
Understanding the Technology
Depending on the type of server being set up, a server-class machine with specialized hardware is usually needed. Rather than a hard drive like most desktops have, servers use a data storage system known as Redundant Array of Inexpensive Disks, or RAID for short. As the name implies, RAID systems are actually several disk drives configured to act like one. This improves efficiency, and if one disk fails, the array continues to function with little or no loss of data. Commercial servers also need fast processors, enough RAM to service the estimated number of requests, and an uninterrupted power supply. Many organizations have redundancies built into their system to accommodate failover; that is, if one server goes down, the standby server takes over immediately.
Types of Servers
Some of the most common servers in use today are database servers, application servers, mail servers and Web servers. As the name indicates, a database server provides the services and connections for storing, organizing and searching enterprise data. An application server, also called middleware, is the glue that holds the entire system together; it provides the runtime environment for applications and seamlessly coordinates things between the applications and database. Without mail servers, email would not get delivered; as bad or worse to go down would be Web servers, which are what allow people to surf the Web. Other types of critical servers in use are FTP servers, print servers, proxy servers, file servers and domain-name servers, to name a few.
Setting Up a Server
Almost any computer can be set up as a server. Many people use slightly obsolete computers to set up their own network servers at home using operating systems like Linux that aren't resource-intensive -- some don't even have graphical user interfaces -- and know that you don't need newer machines to make good servers. Some folks even set up Web servers and use it to host their own site, and the remarkable thing is that this can be done on a shoestring budget given that most of the software you will need is open source and free. Also, unless you're planning on having Web traffic approaching that of Amazon or Google, an old computer should be powerful enough for your server needs. There are some good, easy to understand tutorials on the Web to help you get started (see links in Resources).
In Feburary 2016 06,
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