by Dinesh Thakur

Guided means are those that provide a conductor from one device to the other and include twisted-pair cables, coaxial cables, and fiber optic cables. A signal traveling by any of these means is directed and contained by the physical limits of the medium. Twisted pair and coaxial cable use metallic (copper) conductors that accept and carry electrical current signals. Fiber optic is a glass or plastic cable that accepts and transports signals in the form of light.

 
by Dinesh Thakur

Server: A server is a computer program or device in the network that provides resources, data, services, or programs to the client computer such as login requests processing, files access and storage, internet access, printing access and many other types of services. This architecture is called the client-server model. Servers are often referred to as dedicated.



 
by Dinesh Thakur

FDDI stands for Fiber Distributed Data Interface. It is a high-speed, high-bandwidth network based on optical transmissions. It is most often used as a network backbone, for connecting high-end computers (mainframes, minicomputers, and peripherals), and for LANs connecting high-performance engineering, graphics, and other workstations that demand a rapid transfer of large amounts of data. It can transport data at a rate of 100 Megabits per second and can support up to 500 stations on a single network. FDDI was designed to run through fiber cables, transmitting light pulses to convey information between stations, but it can also run on copper using electrical signals. It is relatively expensive to implement, although the mixing of fiber-optic with copper cabling can hold down the cost.



 
by Dinesh Thakur

Digital Equipment Corporation (DEC) has given support to network connectivity for networks of its own and networks of other vendors also. DEC has its own architecture known as Digital Network Architecture (DNA) the product that implements the architecture is known as DEC net. The DNA was developed during 1974, to provide communication facility between various DEC systems.

 
by Dinesh Thakur

The Systems Network Architecture (SNA) from IBM uses a 7 layer architecture similar to the OSI model.

 
by Dinesh Thakur

Definition:  General Packet Radio Service is a packet-based wireless communication service. It promises data rate up to 114 kbps. It is a standard technology which extends the Global system. It abbreviated as GPRS. It is designed to replace the current circuit-switched services.

General Packet Radio Service is a non-voice and high-speed technology which is useful for the GSM networks. We make use of GPRS so that we can enable connections which depend on the internet protocol. As we know, IP supports a wide variety of applications. We can send and receive the compressed data and large volume data over the mobile network by using GPRS as the packet switching system used. So, before sending the data, it breaks the whole data into packets and then shifts them through the network. Now the data again assembled at the recipient side.



 
by Dinesh Thakur

Cluster computing or High-Performance computing frameworks is a form of computing in which bunch of computers (often called nodes) that are connected through a LAN (local area network) so that, they behave like a single machine. A computer cluster help to solve complex operations more efficiently with much faster processing speed, better data integrity than a single computer and they only used for mission-critical applications.



 
by Dinesh Thakur

The TCP / IP layer set corresponds to the OSI reference model levels as follows:

This correspondence is theoretical because, as the TCP / IP protocols developed before the OSI reference model, there are substantial differences, such as:



 
by Dinesh Thakur

In 1969, the Advanced Research Projects Agency (ARPA), belonging to the United States Department of Defense, funded a project. ARPA established a network of switching packets of computers connected through rented point-to-point lines called the Network of the Agency for Advanced Research Projects (ARPANET), which provided the basis for the first investigations in network interconnection. The conventions developed by ARPA to specify how individual computers could communicate over the network became TCP / IP.

The TCP / IP protocol, acronym for Transmission Control Protocol / Internet Protocol, protocols used to control Internet transmission. It allows different types of computers or computers to communicate through heterogeneous networks.



 
by Dinesh Thakur

Multiplexing or (muxing) - To combine multiple signals (analog or digital) for transmission over a single line or media. A common type of multiplexing combines several low-speed signals for transmission over a single high-speed connection. In other words, we can say that Muxing used for sharing of a medium and its link by two or more devices. It can provide both Efficiency and Privacy.

 
by Dinesh Thakur

Modulation has defined as the process of combining an input signal m (t) and a frequency carrier FC to produce an S (t) signal whose bandwidth is (usually) centred around FC. In the case of digital data, the justification of the modulation must be clear: it is necessary when there is only the possibility of analogue transmission, to convert the digital data into analogues. However, when the data is analogue, the justification is not so apparent. After all, voice signals are transmitted through telephone lines using their original spectrum (this is called baseband transmission). There are two main reasons:

 
by Dinesh Thakur

The term variable-length subnet mask (VLSM) refers to the fact that a network can configure with different masks. The basic idea behind VLSM is to offer more flexibility by dividing a network into multiple subnets while optimizing the allocation of varying amounts of host space between subnets. Without VLSM, only one subnet mask can apply to an entire network. It would restrict the number of hosts given the number of subnets required. If you select the mask so that it has enough subnets, you might not be able to assign enough host numbers in each subnet. The same is true for hosts; A mask that allows enough hosts may not provide enough subnet space. VLSM provides the ability to assign subnets with varying numbers of hosts, allowing the network administrator to use the address space better.

 
by Dinesh Thakur

In order to provide computer to computer communication via Internet, we need a global addressing scheme. Such an addressing is provided by Internet Protocol (IP) at the network layer.
It is a 32-bit address This is called an IP address or logical address. Which is made up of the network ID, plus a unique host ID. This address is typically represented with the decimal value of each octet separated by a period (for example, 192.168.7.27).   Every Host and router on the internet has an IP Address. This IP address is unique and no two devices on the Internet can have the same address at the same time.



 
by Dinesh Thakur

An intranet is a private computer network that uses Internet Protocol technologies to securely share any part of an organization's information or operational systems within that organization. The term is used in contrast tointernet,a network between organizations, and instead refers to a network within an organization.



 
by Dinesh Thakur

ADSL stands for Asymmetric Digital Subscriber Line. ADSL is a type of DSL line and is one of the technologies vying to replace ISDN. It consists of the transmission of digital data supported by the symmetric pair of copper carried by the conventional telephone line or subscriber line, as long as the range does not exceed 5.5 km measured from the Telephone System, or there are no other services on the same cable that may interfere. It is a broadband Internet access technology, which implies a higher rate of data transmission in the data transfer, and supports simultaneous Internet browsing and phone use.

 
by Dinesh Thakur

Dynamic Host Configuration Protocol (DHCP) is a protocol used by networked devices or clients to obtain the parameters necessary for operationin an Internet Protocol network. This protocol reduces system administration workload, allowing devices to be added to the network with little or no manual configurations. Dynamic Host Configuration Protocol is a way to administrator network parameter assignment from a single DHCP server, or a group of DHCP servers arranged in a fault-tolerant manner. Even in small networks,



 
by Dinesh Thakur

Before discussing about Domain Name Server: we are going to explain some factor and simple difference between Domain Name Server and Domain Name System.

 
by Dinesh Thakur

What is http: HTTP full form HyperText Transfer Protocol used mainly to access data on the World Wide Web. HTTP is a Server and Client communication Protocol, which is primarily set of rules for formating and transferring webpage data (text, images, video and Multimedia files) over the world wide web. This is the Protocol used to create communication between Web Servers and Web Users. HTTP is an application layer Protocol that works on the top of the TCP/IP suite of Protocols.

 
by Dinesh Thakur

VPN (Virtual Private Network) Definition: VPN meaning that it is a private point-to-point connection between two machines or networks over a shared or public network such as the internet. A Virtual Private Network is a combination of software and hardware. VPN (Virtual Private Network) technology, can be use in organization to extend its safe encrypted connection over less secure internet to connect remote users, branch offices, and partner private, internal network. VPN turn the Internet into a simulated private WAN.



 
by Dinesh Thakur

The INSERT statement is used to add new row to a table. To insert new row(s) into a table, the table must be in your own schema or you must have INSERT privilege on the table. Only one row is inserted at a time with this syntax. You can insert literal values (26.5, 'DINESH), expres­sions containing operators and functions, null values etc. only.

 

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About Dinesh Thakur

Dinesh ThakurDinesh Thakur holds an B.SC (Computer Science), MCSE, MCDBA, CCNA, CCNP, A+, SCJP certifications. Dinesh authors the hugely popular blog. Where he writes how-to guides around Computer fundamental , computer software, Computer programming, and web apps. For any type of query or something that you think is missing, please feel free to Contact us.