Monday, 1 October 2018

What are the types of cable?

What are the types of cable?

A. Twisted Pair
    a. STP
    b. UTP

STP

Often abbreviated STP, a type of copper telephone wiring in which each of the two copper wires that are twisted together are coated with an insulating coating that functions as a ground for the wires. The extra covering in shielded twisted pair wiring protects the transmission line from electromagnetic interference leaking into or out of the cable. STP cabling often is used in Ethernet networks, especially fast data rate Ethernets.

                                                                                                         UTP

Unshielded twisted pair (UTP) is a ubiquitous type of copper cabling used in telephone wiring and local area networks (LANs). There are five types of UTP cables -- identified with the prefix CAT, as in category -- each supporting a different amount of bandwidth.

STRAIGHT THROUGH CABLE

A straight-through cable is a type of twisted pair cable that is used in local area networks to connect a computer to a network hub such as a router. This type of cable is also sometimes called a patch cable and is an alternative to wireless connections where one or more computers access a router through a wireless signal.
 CROSSOVER CABLE

A crossover cable is a type of cable installation that is used for the interconnection of two similar devices. It is enabled by reversing the transmission and receiving pins at both ends, so that output from one computer becomes input to the other, and vice versa.

Monday, 17 September 2018

What are the types of computer network?

LAN
A local area network (LAN) is a group of computers and associated devices that share a common communications line or wireless link to a server. Typically, a LAN encompasses computers and peripherals connected to a server within a distinct geographic area such as an office or a commercial establishment. Computers and other mobile devices use a LAN connection to share resources such as a printer or network storage.
A local area network may serve as few as two or three users (for example, in a small-office network) or several hundred users in a larger office. LAN networking comprises cables, switches, routers and other components that let users connect to internal servers, websites and other LANs via wide area networks.
WAN
A wide area network (WAN) is a network that exists over a large-scale geographical area. A WAN connects different smaller networks, including local area networks (LANs) and metro area networks (MANs). This ensures that computers and users in one location can communicate with computers and users in other locations. WAN implementation can be done either with the help of the public transmission system or a private network.
MAN

metropolitan area network (MAN) is a computer network that interconnects users with computer resources in a geographic area or region larger than that covered by even a large local area network (LAN) but smaller than the area covered by a wide area network (WAN). The term MAN is applied to the interconnection of networks in a city into a single larger network which may then also offer efficient connection to a wide area network. The term is also used to describe the interconnection of several local area networks in a metropolitan area through the use ofpoint-to-point connections between them.[1][2]
PAN
personal area network (PAN) is a computer network for interconnecting devices centered on an individual person's workspace. A PAN provides data transmission amongst devices such as computerssmartphonestablets and personal digital assistants. PANs can be used for communication amongst the personal devices themselves, or for connecting to a higher level network and the Internet (an uplink) where one master device takes up the role as gateway. A PAN may be carried over wired computer buses such as USB.

https://en.wikipedia.org/wiki/Local_area_network
https://en.wikipedia.org/wiki/Wide_area_network
https://en.wikipedia.org/wiki/Metropolitan_area_network
https://en.wikipedia.org/wiki/Personal_area_network

What are the types of network topology?

Network Topology refers to the layout of a networkand how different nodes in a network are connected to each other and how they communicate. 


                                                          MESH TOPOLOGY

A network setup where each computer and network device is interconnected with one another, allowing for most transmissions to be distributed, even if one of the connections go down. It is a topology commonly used for wireless networks. Below is a visual example of a simple computer setup on a network using a mesh topology.
Mesh topology
A mesh topology can be a full mesh topology or a partially connected mesh topology.
In a full mesh topology, every computer in the network has a connection to each of the other computers in that network. The number of connections in this network can be calculated using the following formula (n is the number of computers in the network): n(n-1)/2
In a partially connected mesh topology, at least two of the computers in the network have connections to multiple other computers in that network. It is an inexpensive way to implement redundancy in a network. In the event that one of the primary computers or connections in the network fails, the rest of the network continues to operate normally.

Advantages of a mesh topology

  • Can handle high amounts of traffic, because multiple devices can transmit data simultaneously.
  • A failure of one device does not cause a break in the network or transmission of data.
  • Adding additional devices does not disrupt data transmission between other devices.

Disadvantages of a mesh topology

  • The cost to implement is higher than other network topologies, making it a less desirable option.
  • Building and maintaining the topology is difficult and time consuming.
  • The chance of redundant connections is high, which adds to the high costs and potential for reduced efficiency.                                                                                                                                                HYBRID TOPOLOGY                                   
                                                                                                           A
     hybrid topology is a type of network topology that uses two or more differing network topologies. These topologies include a mix of bus topology, mesh topology, ring topology, star topology, and tree topology.

Linear bus topology

Updated: 04/26/2017 by Computer Hope
A linear bus network topology.Linear bus topology is a type of network topologyin which each device is connected one after the other in a sequential chain (shown right). In this case, the bus is the network connection between the devices, and if any link in the network chain is severed, all network transmission is halted. It works well for small networks because it is simple to set up and utilizes shorter cables since each device is connected to the next. It is a poor solution for larger networks, however since the entire network relies on each connection, and network speed is reduced as more devices are added.


Star Topology

Updated: 01/24/2018 by Computer Hope
Star topologyAlternatively referred to as a star networkstar topology is one of the most common network setups. In this configuration, everynode connects to a central network device, like a hubswitch, or computer. The central network device acts as a server and the peripheral devices act as clients. Depending on the type ofnetwork card used in each computer of the star topology, a coaxial cable or a RJ-45 network cable is used to connect computers together.
The picture to the right shows how this network setup gets its name, as it is shaped like a star.

Ring topology

Updated: 01/24/2018 by Computer Hope
Ring topologyring topology is a network configuration in which device connections create a circular data path. Each networked device is connected to two others, like points on a circle. Together, devices in a ring topology are referred to as a ring network.
In a ring network, packets of data travel from one device to the next until they reach their destination. Most ring topologies allow packets to travel only in one direction, called a unidirectional ring network. Others permit data to move in either direction, called bidirectional.
The major disadvantage of a ring topology is that if any individual connection in the ring is broken, the entire network is affected.
Ring topologies may be used in either local area networks (LANs) or wide area networks (WANs). Depending on the type of network card used in each computer of the ring topology, acoaxial cable or a RJ-45 network cable is used to connect computers together.

Additional information

In the past, the ring topology was most commonly used in schools, offices, and smaller buildings where networks were smaller. However, today, the ring topology is seldom used, having been switched to another type of network topology for improved performance, stability, or support.

https://www.computerhope.com/jargon/m/mesh.htm
https://www.computerhope.com/jargon/l/linear-bus-topology.htm
https://www.computerhope.com/jargon/s/startopo.htm
https://www.computerhope.com/jargon/r/ringtopo.htm

Wednesday, 25 July 2018

How to be a responsible netizen?

 Do not engage in cyberbullying and other internet crimes.   


      It's okay to act cool in social media , but getting involved in serious crimes like cyberbullying or stealing someone's identity is not good. Never criticize a particular person without knowing the real reason behind the issue.

   


                                                                                                                                                          Be a human





       It can easy to forget that you are talking to real people and not computers when you're behind the screen. So always remember that there is another person on the other side. They also have feelings so be careful what you say , don't be judgmental , and respect each others point of view.


Don't abuse your power



           Some people online have more power or influence than others , like those who have a lot of followers. Whatever they post online will surely reach a lot of netizens since they have a lot of fans. However , being more influential or powerful does not give you the right to hurt others.