Uniform Resource Identifier (URI)

Uniform Resource Identifier (URI) is a string of characters used to identify a name of a web resource. Such identification enables interaction with representations of the web resource over a network (typically the World Wide Web) using specific protocols. Schemes specifying a concrete syntax and associated protocols define each URI.

Relationship to URL and URN

URIs can be classified as locators (URLs), as names (URNs), or as both. A uniform resource name (URN) functions like a person's name, while a uniform resource locator (URL) resembles that person's street address. In other words: the URN defines an item's identity, while the URL provides a method for finding it.

The ISBN system for uniquely identifying books provides a typical example of the use of URNs. ISBN 0-486-27557-4 (urn:isbn:0-486-27557-4) cites unambiguously a specific edition of Shakespeare's play Romeo and Juliet. To gain access to this object and read the book, one needs its location: a URL address. A typical URL for this book on a Unix-like operating system would be a file path such as file:///home/username/books/RomeoAndJuliet.pdf, identifying the electronic book library saved on a local disk drive. So URNs and URLs have complementary purposes.

History About URI (Uniform Resource Identifier)

• Refinement of specifications

In December 1994, RFC 1738 formally defined relative and absolute URLs, refined the general URL syntax, defined how to resolve relative URLs to absolute form, and better enumerated the URL schemes then in use. The agreed definition and syntax of URNs had to wait until the publication of RFC 2141 in May 1997.

The publication of RFC 2396 in August 1998 saw the URI syntax become a separate specification and most of the parts of RFCs 1630 and 1738 relating to URIs and URLs in general were revised and expanded by the IETF. The new RFC changed the significance of the "U" in "URI": it came to represent "Uniform" rather than "Universal". The sections of RFC 1738 that summarized existing URL schemes migrated into a separate document. IANA keeps a registry of those schemes, RFC 2717 first described the procedure to register them.

In December 1999, RFC 2732 provided a minor update to RFC 2396, allowing URIs to accommodate IPv6 addresses. Some time later, a number of shortcomings discovered in the two specifications led to the development of a number of draft revisions under the title rfc2396bis. This community effort, coordinated by RFC 2396 co-author Roy Fielding, culminated in the publication of RFC 3986 in January 2005. This RFC, as of 2009 the current version of the URI syntax recommended for use on the Internet, renders RFC 2396 obsolete. It does not, however, render the details of existing URL schemes obsolete; RFC 1738 continues to govern such schemes except where otherwise superseded – RFC 2616 for example, refines the 'http' scheme. Simultaneously, the IETF published the content of RFC 3986 as the full standard STD 66, reflecting the establishment of the URI generic syntax as an official Internet protocol.

In August 2002, RFC 3305 pointed out that the term 'URL' has, despite its widespread use in the vernacular of the Internet-aware public at large, faded into near obsolescence. It now serves only as a reminder that some URIs act as addresses because they have schemes that imply some kind of network accessibility, regardless of whether systems actually use them for that purpose. As URI-based standards such as Resource Description Framework make evident, resource identification need not suggest the retrieval of resource representations over the Internet, nor need they imply network-based resources at all.

On November 1, 2006, the W3C Technical Architecture Group published 'On Linking Alternative Representations To Enable Discovery And Publishing', a guide to best practices and canonical URIs for publishing multiple versions of a given resource. For example, content might differ by language or by size to adjust for capacity or settings of the device used to access that content.

The Semantic Web uses the HTTP URI scheme to identify both documents and concepts in the real world: this has caused confusion as to how to distinguish the two. The Technical Architecture Group of W3C (TAG) published an e-mail in June 2005 on how to solve this problem. The e-mail became known as the httpRange-14 resolution. To expand on this (rather brief) email, W3C published in March 2008 the Interest Group Note Cool URIs for the Semantic Web. This explains the use of content negotiation and the 303-redirect code in more detail.

• Name, address, and identify resources

URIs and URLs have a shared history. In 1994, Tim Berners-Lee’s proposals for HyperText implicitly introduced the idea of a URL as a short string representing a resource that is the target of a hyperlink. At the time, people referred to it as a 'hypertext name' or 'document name'.

Over the next three and a half years, as the World Wide Web's core technologies of HTML (the HyperText Markup Language), HTTP, and web browsers developed, a need to distinguish a string that provided an address for a resource from a string that merely named a resource emerged. Although not yet formally defined, the term Uniform Resource Locator came to represent the former, and the more contentious Uniform Resource Name came to represent the latter.

During the debate over defining URLs and URNs it became evident that the two concepts embodied by the terms were merely aspects of the fundamental, overarching notion of resource identification. In June 1994, the IETF published Berners-Lee's RFC 1630: the first RFC that (in its non-normative text) acknowledged the existence of URLs and URNs, and, more importantly, defined a formal syntax for Universal Resource Identifiers — URL-like strings whose precise syntaxes and semantics depended on their schemes. In addition, this RFC attempted to summarize the syntaxes of URL schemes in use at the time. It also acknowledged, but did not standardize, the existence of relative URLs and fragment identifiers.

Example Of Absolut URI

http://example.org/absolute/URI/with/absolute/path/to/resource.txt

 

 

Wi-fi (Wireless Fidelity)

Wi-fi (Wireless Fidelity) is a well-known technology that utilizes electronic equipment to exchange data wirelessly (using radio waves) through a computer network, including high-speed Internet connection. Wi-Fi Alliance Wi-Fi defines as "the product of wireless local area networks (WLAN) based on any standard Institute of Electrical and Electronics Engineers (IEEE) 802.11". Even so, since most WLANs today are based on these standards, the term "Wi-Fi" is used in common English as a synonym for "WLAN".

A tool that can use Wi-Fi (such as a personal computer, video game console, smart phone, tablet, or digital audio player) can be connected to a network resource such as the Internet via a wireless network access point. Access point (or hotspot) as it has a range of around 20 meters (65 feet) indoors and broader outdoors. Hotspot coverage can cover an area of ​​a room with walls that block radio waves or a few square miles - This can be done by using multiple access points overlap.

"Wi-Fi" is a trademark of Wi-Fi Alliance and the brand name for products using the IEEE 802.11 family of standards. Only products that complete the Wi-Fi interoperability certification testing Wi-Fi Alliance that may use the name and trademark "Wi-Fi CERTIFIED".

Wi-Fi has a history of security changes. First encryption systems, WEP, proved easily penetrated. Higher quality protocols, WPA and WPA2, then added. However, an optional feature that was added in 2007 called Wi-Fi Protected Setup (WPS), has loopholes that allow attackers to get WPA or WPA2 password router remotely within a few hours. A number of companies advised to turn off the WPS feature. Wi-Fi Alliance since the update test plans and certification program to ensure all new equipment certified AP PIN immune from harsh attacks.

Wi-fi History

802.11 technology history began at the U.S. Federal Communications Commission's decision in 1985 to release a GSM bands for unlicensed use. In 1991, NCR Corporation with AT & T find predecessors 802.11 intended for cashier systems. The first wireless products under the name WaveLAN.

Vic Hayes dubbed the "Father of Wi-Fi". He was involved in the design of the first IEEE standard.

A large number of patents by many companies using the 802.11 standard. In 1992 and 1996, CSIRO Australia organization obtained a patent for a method that would be used in the Wi-Fi signal to remove interference. In April 2009, 14 technology companies agreed to pay $ 250 million to CSIRO for violating their patents. This push Wi-Fi is touted as Australia's findings, although it has been a topic of some controversy. CSIRO won a lawsuit worth $ 220 million for patent infringement in 2012 Wi-Fi is asking global firms in the United States pay for the privilege to CSIRO's license valued at $ 1 billion.

In 1999, the Wi-Fi Alliance was formed as a trade association to hold the Wi-Fi trademark is used by many products.

Name

The term Wi-Fi, first used commercially in August 1999, coined by a brand consulting firm called Interbrand Corporation. Wi-Fi Alliance hired Interbrand to specify the name of the "easier said than 'IEEE 802.11b Direct Sequence'". Belanger also stated that Interbrand creates a Wi-Fi as a play on the Hi-Fi (high fidelity), they also designed the Wi-Fi logo.

Wi-Fi Alliance initially used the advertising slogan for Wi-Fi, "The Standard for Wireless Fidelity", but later removed from their marketing. Even so, a number of documents from the Alliance in 2003 and 2004 still use the term Wireless Fidelity. There has been no official statement regarding the removal of this term.

Logo yin-yang Wi-Fi interoperability certification indicates a product.

Technology non-Wi-Fi is required to keep the points such as Motorola Canopy are usually called fixed wireless. Alternative wireless technologies include mobile phone standards such as 2G, 3G, or 4G.

Wi-Fi Certification

IEEE does not test equipment to meet their standards. Nonprofit Wi-Fi Alliance was founded in 1999 to fill this gap - to establish and encourage standards of interoperability and backward compatibility, and to promote wireless local area network technology. In 2010, the Wi-Fi Alliance consisted of more than 375 companies around the world. Wi-Fi Alliance encourages the use of Wi-Fi brand to technologies based on the IEEE 802.11 standards from the Institute of Electrical and Electronics Engineers. This includes wireless local area network connection (WLAN) connectivity tool-to-tool (such as Wi-Fi Peer to Peer or Wi-Fi Direct), personal area network (PAN), local area network (LAN), and even the number of connections wide area network (WAN) is limited. Manufacturing companies with membership Wi-Fi Alliance, whose products successfully passed the certification process, the right to mark those products with the Wi-Fi logo.

Specifically, the certification process requires compliance with IEEE 802.11 radio standards, the WPA and WPA2 security standdar, and the EAP authentication standard. Includes optional certification testing IEEE 802.11 draft standards, interaction with cellular phone technology in converged devices, and security features, multimedia, and power savings.

Not all Wi-Fi equipment is sent to get the certification. The lack of Wi-Fi certification does not mean that a device is not compatible with other Wi-Fi devices. If the appliance is eligible or semi-compatible, Wi-Fi Alliance does not need to comment on their mention as a Wi-Fi device, though technically only certified devices are approved. Terms such as Super Wi-Fi, which was initiated by the Federal Communications Commission (FCC) to describe the U.S. plan UHF TV band network in the United States, may be approved or not.

(FTP) File Transfer Protocol

File Transfer Protocol (FTP) is a standard network protocol used to transfer files from one host to another host over a TCP-based network, such as the Internet.

FTP is built on a client-server architecture and uses separate control and data connections between the client and the server. FTP users may authenticate themselves using a clear-text sign-in protocol, normally in the form of a username and password.

But can connect anonymously if the server is configured to allow it. For secure transmission that hides (encrypts) the username and password, and encrypts the content, FTP is often secured with SSL/TLS ("FTPS"). SSH File Transfer Protocol ("SFTP") is sometimes also used instead, but is technologically different.

The first FTP client applications were command-line applications developed before operating systems had graphical user interfaces, and are still shipped with most Windows, Unix, and Linux operating systems. Dozens of FTP clients and automation utilities have since been developed for desktops, servers, mobile devices, and hardware, and FTP has been incorporated into hundreds of productivity applications, such as Web page editors.

The History From FTP (File Transfer Protocol)

The original specification for the File Transfer Protocol was written by Abhay Bhushan and published as RFC 114 on 16 April 1971. Until 1980, FTP ran on NCP, the predecessor of TCP/IP. The protocol was later replaced by a TCP/IP version, RFC 765 (June 1980) and RFC 959 (October 1985), the current specification. Several proposed standards amend RFC 959, for example RFC 2228 (June 1997) proposes security extensions and RFC 2428 (September 1998) adds support for IPv6 and defines a new type of passive mode.

Communication and  transfer

FTP may run in active or passive mode, which determines how the data connection is established. In active mode, the client creates a TCP control connection. In situations where the client is behind a firewall and unable to accept incoming TCP connections, passive mode may be used. In this mode, the client uses the control connection to send a PASV command to the server and then receives a server IP address and server port number from the server, which the client then uses to open a data connection from an arbitrary client port to the server IP address and server port number received. Both modes were updated in September 1998 to support IPv6. Further changes were introduced to the passive mode at that time, updating it to extended passive mode.

The server responds over the control connection with three-digit status codes in ASCII with an optional text message. For example "200" (or "200 OK") means that the last command was successful. The numbers represent the code for the response and the optional text represents a human-readable explanation or request (e.g. <Need account for storing file>). An ongoing transfer of file data over the data connection can be aborted using an interrupt message sent over the control connection.

While transferring data over the network, four data representations can be used:

• ASCII mode: used for text. Data is converted, if needed, from the sending host's character representation to "8-bit ASCII" before transmission, and (again, if necessary) to the receiving host's character representation. As a consequence, this mode is inappropriate for files that contain data other than plain text.
• Image mode (commonly called Binary mode): the sending machine sends each file byte for byte, and the recipient stores the bytestream as it receives it. (Image mode support has been recommended for all implementations of FTP).
• EBCDIC mode: use for plain text between hosts using the EBCDIC character set. This mode is otherwise like ASCII mode.
• Local mode: Allows two computers with identical setups to send data in a proprietary format without the need to convert it to ASCII

For text files, different format control and record structure options are provided. These features were designed to facilitate files containing Telnet or ASA

Data transfer can be done in any of three modes:

• Stream mode: Data is sent as a continuous stream, relieving FTP from doing any processing. Rather, all processing is left up to TCP. No End-of-file indicator is needed, unless the data is divided into records.
• Block mode: FTP breaks the data into several blocks (block header, byte count, and data field) and then passes it on to TCP.
• Compressed mode: Data is compressed using a single algorithm (usually run-length ecording).

Email (Electronic Mail)

Email (Electronic Mail) is a means of sending a letter sent through a computer network (eg Internet). By regular mail senders usually need to pay per delivery (by buying stamps), but electronic mail is generally the cost is the cost to pay for the Internet connection. But there are exceptions such as electronic mail to cell phones, sometimes payment is billed per delivery.

Email History

Email (Electronic mail) has started to be used in the 1960's. At that time the Internet has not been established, there is only a collection of 'mainframe' is formed as a network. Beginning in the 1980s, electronic mail can be enjoyed by the general public. Nowadays many companies heading in different countries due to decreased income communities are not using postal services anymore.

Ratel anatomy, for example:

     Dheniez_007@Yahoo.Com

Description:

• My Email : mailbox name (mailbox) or user name (username) you want to target in the mailserver.
• Makassar.vibriel.net.id : mailserver name where the intended users, the details is :

1. Makassar : subdomain (owned by the holder of the domain name), typically refers to a computer within the domain owner.
2. vibriel : domain name, usually indicates the name of the company / organization / individual (Vibriel)
3. net : second-level domain, indicating that this domain including networking category (net)
4. id : top level domain, indicating that this domain is registered in the domain authority of Indonesia (id)

Method Of Delivery

To send an e-mail we require a mail-client program. Electronic mail that we send will go through a few points before arriving at the destination. For more details see Aaya dog → Internet → POP3 e-mail server provider → recipient e-mail client (on the computer of the recipient) → read the letter recipient.

Visible electronic mail sent only through 5 points (other than the sending computer and receiving). Actually more than that because after leaving the POP3 mail server then it will go through a lot of other servers. There is a possibility that we send electronic mail intercepted others. Therefore when we send e-mails containing sensitive content we should take precautions, to randomize (encrypt) data in the electronic mail (eg using PGP, digital certificates, etc.)

 Ethical use of electronic mail

Ethics in electronic mail with ethics in ordinary writing. There is a formal contents of electronic mail that there are informal. Some important points:

• Do not send electronic mail with attachment (attachment) that is too large (more than 512 kB). Not everyone has fast Internet access, and there is the possibility of the attachment exceeds the capacity of receiving electronic mail, so the recipient mail server will be rejected. In addition, note also that some e-mail providers also apply restrictions on the quantity, type, and size of electronic mail can be received (and sent) users,
• Do not send up (forward) without thinking usability of electronic mail to the intended person.
• Always fill in the subject, do not be left blank.
• In citing the writings of others, always try to quote as needed, do not be so easily that people quote the whole article:

1. In reply electronic mail of others, major parts of which we respond to it, in addition to more clearly also does not take / ration access receiver,
2. writing in the third person quote, remember copyright: quote as little as possible and refer to the original article.

• Do not use all capital letters because it can give the impression you are SHOUTING.
• Use polite words. Sometimes we write something different will be impressed with what we really mean.

 

How To Read Email (electronic Mail)

Electronic mail was originally stored in a mailserver. Usually when someone wears ISP connection for connection to the internet, he will be given a free electronic mail. Electronic mail received will be stored in the ISP mail server.

There are two ways to access electronic mail:

• By using a web browser, such as Mozilla Firefox. This method is referred to as a web-based, meaning that we use the web as an intermediary media to electronic mailboxes. Example: Yahoo! Mail and Gmail. To use it, users must be online. Web-based email service is usually provided by a free email service.
• The access program using electronic mail (e-mail client), such as: Eudora Mail, Outlook Express, Windows Mail, Mozilla Thunderbird, Mutt. By using a program such as this, one must know the configuration that can be obtained from the ISP. The advantage is that it can read e-mail without the need to be constantly connected to the internet and dozens of e-mails can be sent and received simultaneously at once. Other advantages are that this software provides editing functions and reading email offline. Thus the cost of connection to the internet can be saved.

ARPANET (Advanced Research Project Agency Network)

 

ARPAnet (Advanced Research Projects Agency Network)

ARPANET (Advanced Research Projects Agency Network) is a computer network made ​​by ARPA (Advanced Research Project Agency) of the America Department of Defense in 1969.

ARPANET functioned as a means of trial latest computer network technology of his day, such as packet switching technology and into the beginning of the establishment of the current Internet.

Network Control Protocol (NCP) is the first standard network protocols on the ARPANET. NCP perfected and launched in December 1990 by the Network Working Group (NWG) led by Steve Crocker, who is also the inventor of Request for Comments.

ARPANET History

In 1957 the U.S. Department of Defense (DoD - Department of Defense) formed ARPA (Advanced Research Projects Agency) in response to the launch of the Soviet Sputnik. ARPA charge of improving technological capabilities that can be utilized by the military. ARPA actually do not have expert knowledge or laboratory. Owned only a small office and budget (for standard Pentagon) alone. ARPA carry out their duties to provide assistance and perform contracts with universities and companies that have ideas that are considered promising for its operations.

In the mid 1960s, the height of the Cold War, DoD would like to have a command and control network that can defend itself in the event of nuclear war. Traditional telephone networks are considered unsafe. Because if one path is lost, then this may result in the cessation of all conversations that use the network or even the only use part of the network suddenly. To resolve this issue change the direction of DoD research, ARPA.

In cooperation with several universities, ARPA decided that the required DoD network is packet-switching form consisting of a subnet and host computers. In December 1968, the ARPA gave the contract to BBN, a consulting firm in Cambridge, Massachusetts to build the network and make the supporting software.

Although there are flaws in the software problems, in December 1969 successfully launched an experimental network connecting the four vertices are UCLA, UCSB, SRI and Utah University. The fourth node does have various contracts with ARPA, and each node has a host computer that is completely different and incompatible with each other. ARPANET network is growing rapidly soon covers the whole of the U.S. in its first three years.

In addition to helping the growth of the ARPANET is still premature, ARPA also funded research satellite network and mobile packet radio networks. These experiments also showed that the ARPANET protocols that have been there do not suitable to operate on multiple networks. These observations are encouraging more and more research on protocols, culminating in the discovery of the model and the TCP / IP protocol. TCP / IP is specifically designed to handle communication through the internetwork, something that is becoming increasingly important as more networks and LANs that are connected to the ARPANET.

To encourage the use of these new protocols, ARPA entered into several contracts with BBN and the University of California at Berkeley to integrate these protocols into Berkeley UNIX. Researchers at Berkeley developed a program interface (interface) to the network (socket) that makes it easy and write some utility programs, applications and network management to make the system easier to operate.

In 1983, the ARPANET has a large network and it can be considered stable and successful. Until this situation, ARPA network management handed over to the Defense Communications Agency (DCA) to run the ARPANET as an operational network. DCA first thing to do is separate the military network into separate subnets, MILNET, gateway-gateway which has a very strict distinction between MILNET with the rest of the subnet other research.

During the 1980s, additional networks, especially LANs, the more that is connected to the ARPANET. In line with the increased breadth of the network, host-even more expensive. Because the DNS (Domain Naming System) was formed to organize machines into domain-specific and domain mapping host names into IP addresses. Since then, the DNS be generalized systems and distributed databases to store a variety of information related to naming.

In 1990, ARPANET had been composed by the new networks, which is actually born by the ARPANET. After the ARPANET ceased operations and dismantled. Until now, MILNET still operating.

 

ARPAnet History

Softwere And Protocol

 

The starting point for host-to-host communication on the ARPANET in 1969 was the 1822 protocol, which defined the transmission of messages to an IMP. The message format was designed to work unambiguously with a broad range of computer architectures. An 1822 message essentially consisted of a message type, a numeric host address, and a data field. To send a data message to another host, the transmitting host formatted a data message containing the destination host's address and the data message being sent, and then transmitted the message through the 1822 hardware interface. The IMP then delivered the message to its destination address, either by delivering it to a locally connected host, or by delivering it to another IMP. When the message was ultimately delivered to the destination host, the receiving IMP would transmit a Ready for Next Message (RFNM) acknowledgement to the sending, host IMP.

Unlike modern Internet datagrams, the ARPANET was designed to reliably transmit 1822 messages, and to inform the host computer when it loses a message; the contemporary IP is unreliable, whereas the TCP is reliable. Nonetheless, the 1822 protocol proved inadequate for handling multiple connections among different applications residing in a host computer. This problem was addressed with the Network Control Program (NCP), which provided a standard method to establish reliable, flow-controlled, bidirectional communications links among different processes in different host computers. The NCP interface allowed application software to connect across the ARPANET by implementing higher-level communication protocols, an early example of the protocol layering concept incorporated to the OSI model.

In 1983, TCP/IP protocols replaced NCP as the ARPANET's principal protocol, and the ARPANET then became one component of the early Internet.

Network applications

NCP provided a standard set of network services that could be shared by several applications running on a single host computer. This led to the evolution of application protocols that operated, more or less, independently of the underlying network service. When the ARPANET migrated to the Internet protocols in 1983, the major application protocols migrated with it.

• E-mail: In 1971, Ray Tomlinson, of BBN sent the first network e-mail (RFC 524, RFC 561). By 1973, e-mail constituted 75 percent of ARPANET traffic.

• File transfer: By 1973, the File Transfer Protocol (FTP) specification had been defined (RFC 354) and implemented, enabling file transfers over the ARPANET.

Voice traffic: The Network Voice Protocol (NVP) specifications were defined in 1977 (RFC 741), then implemented, but, because of technical shortcomings, conference calls over the ARPANET never worked well; the contemporary Voice over Internet Protocol (packet voice) was decades away.

The Terms in the Internet

The Terms in the Internet For those of you who are new to the Internet, of course, a lot of terms that you may come across and read the still unfamiliar to you. Well, in order to make it easier for you to learn, presented the following list of terms that will often encounter if you're surf-ria. Mandatory to know in order to become more aware and do not miss the info on the internet about the world. Especially for those of you who want to deepen their knowledge in the field on this one and wanted to jump in it. Hopefully useful for you all. Please be listened to.

• ADN (Advanced Digital Network) - Usually refers to a 56Kbps speed leased lines.

• ADSL (Asymetric Digital Subscriber Line) - A type of DSL where the upstream and downstream runs at different speeds. In this case, the downstream is usually higher. A common configuration allows up to 1.544 mbps downstream (megabits per second) and 128 kbps (kilobits per second) upstream. In theory, ASDL can serve speeds up to 9 Mbps downstream and 540 kbps upstream.

• Anonymous FTP - FTP site that can be accessed without having to have a specific login. Standard rules in Anonymous FTP access is by entering "Anonymous" in the Username field and your email address as the password.

• ARPANet - Advanced Research Projects Agency Network. Network that became the forerunner of the formation of the Internet. Built in the late 60s to the early decades of the 70's by the U.S. Department of Defense as an experiment to establish a large-scale network (WAN) that connects computers in different locations with different systems, but can also be accessed as a unit to be able to mutually utilize each resource.

• ASCII - American Standard Code for Information Interchange. Standards that apply throughout the world for a code number that represents the characters, either letters, numbers, and symbols used by the computer. There are 128 standard ASCII characters, each represented by a seven-digit binary numbers ranging from 0000000 to 1111111.

• ASP (Active Server Pages) - is a specification for making dynamic Web pages using ActiveX script. When the browser opens an ASP page, the Web server creating a page with HTML code and then sends it to the browser.

• Backbone - a high-speed line or series of connections that a major pathway within a network.

• Bandwidth - The amount that indicates the number of data that can be passed in a channel of communication in the network in a given time unit.

• Binary - Binary. Information that is entirely composed of 0 and 1. The term usually refers to non-formatted text files, as well as graphics files.

• Bit - Binary Digit. The smallest unit in computing, consisting of a magnitude that has a value between 0 or 1.

• Blog - services on the web that is used to write a journal which is usually updated every day. Blogs are usually used free of charge. But some are paid. Through the blog, we can post our writings about various topics that make us interesting to be read by the public. Activity update the information in the blog is called blogging, while the blog owner is called a blogger.

• bps - Bits Per Seconds. Measure that states how fast data is moved from one place to another.

• Broadband - channel data transmission at high speeds and greater bandwidth capacity than conventional phone lines.

• Browser - is the abbreviation for the term Web Browser. A browser is a program used to access the World Wide Web (or the Internet), and other facilities. Currently there are a number of popular browsers, like Internet Explorer, Netscape Navigator, Opera, and Mozilla, etc..

• Byte - A set of bits that represent a single character. Usually 1 byte will consist of 8 bits, but it could be more, depending on the amount used.

• CGI - Common Gateway Interface. Set of rules that direct how a web server communicates with most software on the same machine, and how some of the software (CGI program) communicates with the web server. Any software can be a CGI program if the software can handle input and output based on a standard CGI.

• cgi-bin - common name used for the directory on the web server where CGI programs are stored.

• Chat - chat can be interpreted as the chatter, but in the Internet world, this term refers to the communication between the members of the Internet users who are on-line. Communication can be text, voice (voice chat) using the headset, and visual (video call) using Web Cam (camera).

• DNS - Domain Name Service. A service on the Internet for a network using TCP / IP. This service is used to identify a computer by name instead of using the IP address (IP address). In short DNS to convert from names to numbers. DNS are decentralized, with each area or level of organization has its own domain. Each providing DNS service for managed domain. A database system that allows TCP / IP applications to translate host names into a single IP address. DNS (Domain Name Service) is a service on the Internet for a network that uses TCP / IP. This service is used to identify a computer by using numbers instead of names (Internet addresses). Computers on the Internet is identified by a number, ie IP numbers. For example, a computer has an IP number 192.168.1.1 {}. Computers easier to work with numbers, while humans more easily remember the name. Computer in this example can be named {Gareng}, for example. In short DNS names to make the conversion from angka.DNS are decentralized, with each area or level of organization has its own domain. Each providing DNS service for managed domain. To find the IP address of a machine (computer) on the Internet can be used several programs.

• DSL - Digital Subscriber Line. A method of data transfer over regular phone lines. DSL circuit is configured to connect two specific locations, such as in connection Leased Line (DSL different from the Leased Line). Connections via DSL is much faster than the connections over regular phone lines even though they both use copper wires. Configuration allows the upstream and downstream DSL running at different speeds (see ASDL) and the same speed (see SDSL). DSL offers a cheaper alternative compared to ISDN.

• Domain - In the world of internet or web, domain is the name used to identify a computer address.

• Download - The term for the activities of copying the data (usually a file) from a computer that is connected in a network to a local computer. In other words, the transfer of data via the digital communication of a larger system or central (host or server) to a smaller system (client). The download process is the opposite of upload.

• Downstream - The term that refers to the speed of the flow of data from another computer to a local computer via a network. This term is the opposite of the upstream.

• E-coomerce (electronic commerce) is a business transaction carried out with the help of online computer networks. The transaction is the seller and the purchase of goods and services as well as payments made through the digital communication. The technologies used include Internet and electronic data interchange (EDI).

• E-mail - Electronic Mail. Messages sent from one address to another via a local area network (LAN) or the Internet. If the first, the data is sent only in the form of text, now with the e-mail may contain images, sound, and even video clips. An email address that represents a lot of email addresses at once called a mailing list. An email address username@host.domain usually have some sort of format, for example: myname@mydomain.com.

• FAQ - Frequently Asked Questions Shorthand or "frequently asked questions? . FAQ feature is one website that provides answers to a list of frequently asked questions relating to the service or use of the information presented by the website. Highly recommended read FAQ before you explore any further pages of a web, so you get a general idea of ​​the website.

• Firewall - A combination of hardware and software that separates a network into two or more parts for security reasons.

• FTP - File Transfer Protocol. Standard protocol for traffic activity files (upload or download) between two computers connected to the Internet network. Most FTP system requires to be accessed only by those who have a right to it with a certain login mengguinakan. Partly accessible to the public anonymously. FTP sites are called anonymous FTP.

• Gateway - In a technical sense, the term refers to the hardware and software settings that translate between two different protocols. More general sense of this term is a mechanism that provides access to a different system which is connected in a network.

• GPRS - General Packet Radio Service. One of the wireless communication standard (wireless). Compared with the protocol WAP, GPRS has advantages in speed that can reach 115 kbps and support broader applications, including graphics and multimedia applications.

• Home Page / Homepage - homepage of a website. Another notion is that in setting the default page for a web browser.

• Host - A computer in a network that provides services to other computers that are connected in the same network.

• HTML - Hypertext Markup Language, is a variant of SGML that is used to exchange documents via the HTTP protocol.

• HTTP - Hyper Text Transfer Protocol, a protocol designed to transfer HTML documents used in the World Wide Web.

• HTTPD - is viewed World Wide Web.

• IMAP - Internet Message Access Protocol. Protocol designed for accessing e-mail. Another commonly-used protocol is POP.

• Internet - A large number of networks that make up the inter-connection networks (Inter-connected network) are connected through TCP / IP. Internet is a continuation of ARPANet.dan probably the biggest WAN networks that exist today.

• Intranet - A private network with a hierarchical system and the same with the Internet but is not connected to the Internet network and only used internally in abundance.

• IP Address - The IP address (Internet Protocol), which is addressing in the network system which is represented by a series of numbers in the form of a combination of 4 rows of numbers between 0 s / d 255, each separated by a period (.), Ranging from 0.0.0.1 to 255,255 .255.255.

• ISDN - Integrated Services Digital Network. Basically, ISDN is a way to serve the data transfer at higher speeds over regular phone lines. ISDN allows data transfer speeds up to 128,000 bps (bits per second). Unlike DSL, ISDN can be connected with other locations such as telephone lines, all the locations are also connected to the ISDN network.

• ISP - Internet Service Provider. Designation for internet service providers.

• Leased Line - A telephone line or fiber optic cable that rented for use 24 hours a day to connect one location to another. High-speed internet typically use this channel.

• Login - identifier to access a closed system, consisting of a username (also called the login name) and passwords (passwords).

• Mailing List - It is also often termed as the mailing list, which is an email address that is used by a group of Internet users to engage in exchange of information. Any messages sent to a mailing address, it will automatically be forwarded to the email address of all members. Mailing lists are generally used as a means of discussion or exchange of information among its members.

• MIME - Multi-Purpose Internet Mail Extensions. Email extension that was created to facilitate the attachment file delivery via email.

• MTA - Mail Transport Agent. Software that works to deliver e-mail to the user. The program for reading e-mails known as MUA (Mail User Agent).

• Network - In the terminology of computers and the Internet, the network is a set of two or more computer systems are coupled and form a network. Internet is actually a network with a very large scale.

• NNTP - Network News Transfer Protocol. Protocol used to access or transfer articles posted in Usenet news. News reader program (news reader) use this protocol to access the news. NNTP protocol works on top of TCP / IP using port 119.

• Node - A single computer that is connected to a network.

• Packet Switching - A method used to move data in the Internet network. In packet switching, all the data packets sent from a node will be split into multiple parts. Each section has a description of the origin and destination of the packet data. This allows a large number of pieces of data from multiple sources simultaneously transmitted through the same channel, and then sorted and directed to different routes through the router.

• PERL - A programming language developed by Larry Wall is often used to implement CGI scripts on the World Wide Web. Implemented in a Perl language interpreter is available for various operating systems, including Windows, Unix to Macintosh.

• PHP - is short for HyperText Preprocessor, originally an acronym for Personal HomePage. PHP is a programming language that is usually written with HTML code. Unlike HTML which is sent directly to the browser, PHP parsing scripts used by the PHP binary in the server computer. HTML element is left but the PHP code is executed first and the results in an HTML form is sent to the user's browser. PHP code is able to run the database commands, create images, read and write files, as well as other capabilities that have no limits.

• POP - Post Office Protocol. Standard protocol used to retrieve or read e-mail from a server. POP protocol is the last and most popular use is POP3. Other protocols are also often used is IMAP. As for sending an email to an SMTP server to use.

• PPP - Point to Point Protocol. A TCP / IP protocol that is commonly used to connect a computer to the Internet through a phone line and modem.

• PSTN - Public Switched Telephone Network. Designation for a conventional phone line cables.

• RFC - Request For Comments. Designations for the results and the process for creating a standard on the Internet. A new standard was proposed and published on the internet as a Request For Comments. These proposals will then be reviewed by the Internet Engineering Task Force (IETF), a body that regulates standards on the internet. If the standards are applied, then it will remain known as RFCs with a reference number or specific name, for example, a standard format for email is RFC 822.

• Router - A computer or software package that is devoted to dealing with the connection between two or more networks are connected through packet switching. Router works by looking at the destination address and the source address of the packets of data that pass through it and decide the route to be used by the data packets to a destination.

• SDSL - Symmetric Digital Subscriber Line. One type of DSL that allows the transfer of data to the upstream and downstream runs at the same speed. SDSL generally work at a speed of 384 kbps (kilobits per second).

• SGML - Standard Generalized Markup Language. Popular name of the ISO Standard 8879 (1986) which is a standard ISO (International Organization for Standardization) to exchange documents electronically in the form of hypertext.

• SMTP - Simple Mail Transfer Protocol. Standard protocol used to transmit

• email to a server on the Internet. For the purposes of making an email, use the POP protocol.

• Spam - refers to the practice of sending commercial messages or advertisements to a large number of news groups or email that is actually not willing or are not interested in receiving such messages.

• TCP / IP - Transmission Control Protocol / Internet Protocol. A set of standard protocols used to connect computer networks and put traffic in the network. This protocol set allowable data formats, error handling (error handling), message traffic, and other communications standards. TCP / IP must be able to work on all types of computers, without being influenced by differences in hardware and operating system used.

• Telnet - The software is designed to access a remote host with a text-based terminals, for example with VT100 emulation.

• UDP - User Datagram Protocol. One of the protocols for data transfer purposes that is part of the TCP / IP. Referring to the UDP data packets that do not provide information about their home address when a data packet is received.

• Upload - To transfer of data (a file) from a local computer connected to other computers in a network. The opposite of this activity is called downloading.

• Upstream - The term that refers to the speed of the flow of data from the local computer to other computers connected via a network. This term is the opposite of the downstream.

• URI - Uniform Resource Identifier. An address that points to a resource on the internet. URIs typically consist of a section called the scheme (scheme), which followed an address. URI format accessible to the scheme :/ / alamat.resource or scheme: alamat.resource. For example, resource URI address yahoo.com http://yahoo.com show that the scheme is via HTTP While HTTP is a scheme that is often used, but still available other schemes, such as telnet, FTP, News, and so on.

• URL - Uniform Resource Locator. This term is basically the same as the URI, but URI is more widely used term to replace the URL in technical specifications.

• Usenet - Usenet news, or also known as "net news" or "news" only, is a very large bulletin board and spread all over the world that can be used to exchange articles. Anyone can access the Usenet news with specific programs, which is usually called a newsreader. Access to a news server can be done using the NNTP protocol or by reading directly to the spool directory to the directory where the news article was (way past is rarely done).

• UUENCODE - Unix to Unix Encoding. A method for mengkonfersikan file in binary format to ASCII in order to be sent via email.

• VoIP - Voice over IP. VoIP is a mechanism to make phone calls (voice) conversation with the laying of the data over the Internet or Intranet (which uses IP technology).

• VPN - Virtual Private Network. This term refers to a network that some of them are connected to the Internet network, but the data traffic over the Internet from this network has undergone a process of encryption (scrambling).

• WAP - Wireless Application Protocol. Standard protocols for wireless applications (such as those used in cell phones). WAP is the result of collaboration between the industry to create an open standard (open standard). WAP is based on Internet standards, and some of the protocols that have been optimized for wireless environments. WAP works in text mode with a speed of about 9.6 kbps. Later also developed the GPRS protocol which has several advantages over WAP.

• Webmail - Facilities sending, receiving, or reading email via the web means.

• Wi-Fi - Wireless Fidelity. Is the industry standard for the wireless transmission of data (LAN) standard being developed by the IEEE 802.11 specification.

• World Wide Web - Often abbreviated as WWW or "web", namely a system whereby the information in the form of text, images, sounds, and others presented in the form of hypertext and can be accessed by software called a browser. Information on the web is generally written in HTML format. Other information presented in graphical form (in the format of GIF, JPG, PNG), voice (in AU format, WAV), and other multimedia objects (such as MIDI, Shockwave, Quicktime Movie, 3D World). WWW is run in a server called HTTPD.

• XML - Extensible Markup Language. Further development of the HTML format used in the World Wide Web. XML has a number of advantages over HTML, including more structured documents, allowing manipulation of data display without having to deal with the webserver, and the exchange of data between documents.

Modem (Modulator Demodulator)

 

Eksternal Modem 

Modem  (Modulator Demodulator) comes from. Modulator is the part that converts the signal information into the carrier signal (carrier) and ready to be delivered, while the demodulator is the part that separates signaling information (that contain data or messages) of the received carrier signal so that the information can be received well. Modem is a combination of both, meaning that the modem is a two-way communication tool. Each remote communication devices generally use a two-way section called "modem", such as VSAT, Microwave Radio, and so forth, but generally the term is better known as the modem hardware that is often used for communication on the computer.

Data from the computer in the form of digital signals given to the modem to be converted into an analog signal, when the modem receives data from the outside in the form of an analog signal, turn the modem back into a digital signal that can be further processed by a computer. Analog signals can be transmitted through multiple media such as telephone and radio telecommunications.

Upon arrival at the destination modem, analog signals are converted into digital signals and transmitted back to the computer. There are two types of modems are physical, ie an external modem and an internal modem.

 

Internal Modem

Kind Of Modem (ModulatorDemodulator)

There are 6 Type Modem we are Recognize it  is :

1. ISDN modem
2. GSM modem
3. Analog modem is a modem that makes analog signals into digital signals
4. ADSL modem

• Modem ADSL technology (Asymetric Digital Subscribe Line) which allows surfing the internet and using analog phones simultaneously. It's easy, for ADSL is given a device called a splitter or divider line. Splitter position when placed in front of the incoming phone line. That is, not recommended for forking line to ADSL modem with voice directly. Splitter tool is useful to remove nuisance when using the ADSL modem. With Splitter both can run simultaneously, so that users can answer and someone with a regular phone call. On the other hand, users can still connect to the Internet via the ADSL modem.

    5. Cable modem is a modem that receives data directly from the service provider through cable TV

    6. CDMA modem

• CDMA modem is a modem that uses a frequency of 800 MHz CDMA or CDMA 1x. And most recently using frequency-EVDO Rev A (3G equivalent) and the latest technology is CDMA EVDO Rev-B.