Unit 3 : Network Addresses

NETWORK ADDRESSES

More commonly known as IP Address. It is any logical or physical address that uniquely distinguishes a network node or device over a computer or telecommunications network. It is also the numeric address of a computer connected to the network. 

192.168.1.1 is an example of a Network Address

In addition to that, it is a set of numbers called as "octets" or "dotted decimal" notation, that identifies any network device. 

Note : "octets" comprise of 8 digit number

IP VERSIONS

1. IPV4 

- stands for IP version 4 or The Standard Version. IPv4 addresses are canonically represented in dotted-decimal notation, which consist of four decimal notations, each ranging from 0 to 255, separated by dots. Each part represents a group of 8 bits (octets) of the address.

ex. 

172.16.254.1

2. IPV6

- stands for IP version 6 or The Advanced Version. An IPv6 address is 128 bits long and is arranged in eight groups, each of which is 16 bits. Each group is expressed as four hexadecimal digits and the groups are separated by colons.

ex. 

FE80:CD00:0000:0CDE:1257:0000:211E:729C

BINARY DIGITS

- A binary digit, or bit, is the smallest unit of information in a computer. It is used for storing information and has a value. An individual bit has a value of either 0 or 1, which is generally used to store data and implement instructions in groups of bytes. A computer is often classified by the number of bits it can process at one time or by the number of bits in a memory address. Many systems use four eight-bit bytes to form a 32-bit word.

CLASSES OF IP ADDRESS

1. Class A

- Class A IP address is an IP address in which the first bit of the octet is set to zero, which provides values from 1 to 126. It is also known as the largest IP Address.

ex. 1.37.255.255 

2. Class B

- Class B IP address is an IP address which provides values from 128 to 191. 

ex. 152.32.64.0

3. Class C

- Class C IP address is an IP address which provides values from 192 to 223. 

ex. 198.32.172.89 

4. Class D

- Class D IP address is an IP address which provides values from 224 to 239. It is also used for multi-casting.

5. Class E

- Class E IP address is an IP address which provides values from 240 to 255. Class E is reserved for experimental purposes or for future purposes. 

Note : 127 - Loop Back Function of a network.

Note : Typical home network uses IP Address that starts with 192.168. IP Address such as....192.168.1.1. or 192.168.2.1.

CREATING IP ADDRESS

1. Right click, "My Network Places"
2. Click, "Properties"
3. Right click, "Local Area Connections"
4. Click, "Properties"
5. Click, "TCP/IP"
6. Click, "Properties"

• Obtain an IP Address automatically
• Use the following IP Address : 

            

7. Click, "Ok"

IP CONFIGURATIONS

1. Click, "Start Button"
2. Click, "Run"
3. Type cmd
4. Type ipconfig
5. Type ping [IP address]








https://www.techopedia.com/definition/20969/network-address
https://internetofthingsagenda.techtarget.com/definition/IPv6-address 
techopedia.com/definition/2678/binary-digit-bit
https://www.techopedia.com/definition/17067/class-a-ip-address

What are the Types of Cable?

What is a Cable?

            - It is a medium that connects computer in a network. Alternatively referred to as a cord, connector or plug, a cable is one or more wires covered in a plastic covering that allows for the transmission of power or data between devices. Cable is called a rollover because the pins on one end are all reversed on the other end as though one end of the cable was rotated or rolled over

Types of Cables :

1. Twisted-Pair Cable

           - It is the most common type of cable. It has 8 individual copper wires bundled together and covered with an insulting material. A type of cable that consists of two independently insulated wires twisted around one another. The use of two wires twisted together helps to reduce crosstalk and electromagnetic induction. Most networks contain some twisted-pair cabling at some point along the network. A Twisted-Pair Cable has two types : 

      a. STP (Shielded Twisted Pair)

                 - Often used in "noisy" environments where a shield of metallic foil is wrapped around each of the wire pairs, with an additional overall shielding to protect against excessive electromagnetic interference.

      b. UTP (Unshielded Twisted Pair)

                 - Is the most common form of twisted pair wiring. It is less expensive and easier to work with than STP. Due to its low cost, UTP cabling is used extensively for local-area networks (LANs) and telephone connections. UTP cabling does not offer as high bandwidth or as good protection from interference as coaxial or fiber optic cables, but it is less expensive and easier to work with.

The copper wire is always color-coded with an insulations and they are twisted in pairs for a total of four pairs. 

2. Coaxial Cable 

           - The standard media used by Cable TV Operators. It consist of a plastic insulator that separates the solid copper inner conductor and the woven, copper braid outer conductor. The term coaxial comes from the inner conductor and the outer shield sharing a geometric axis. Coaxial cable was invented by English engineer and mathematician Oliver Heaviside, who patented the design in 1880. Coaxial cable differs from other shielded cables because the dimensions of the cable are controlled to give a precise, constant conductor spacing, which is needed for it to function efficiently as a transmission line.

  

3. Fiber-optic Cable

           - has a reflective coating that allows light beans to travel without outer interference. It  is a high-speed data transmission medium. Because it transmit data via light waves, they can transfer information at the speed of light. Not surprisingly, fiber optic cables provide the fastest data transfer rates of any data transmission medium. They are also less susceptible to noise and interference compared to copper wires or telephone lines. However, fiber optic cables are more fragile than their metallic counterparts and therefore require more protective shielding.

Sources : 

https://techterms.com/definition/fiber_optic_cable

http://networking.layer-x.com/p070300-1.html

https://en.wikipedia.org/wiki/Coaxial_cable

https://www.webopedia.com/TERM/U/UTP.html

https://www.webopedia.com/TERM/T/twisted_pair_cable.html

What are Types of Network Topologies

All About Network Topologies

What are Network Topologies?

Fig 3.1 : How devices are connected to each other

- Network topology is the arrangement of the elements (links, nodes, etc.) of a communication network. Network topology is the topological structure of a network and may be depicted physically or logically. It is an application of graph theory wherein communicating devices are modeled as nodes and the connections between the devices are modeled as links or lines between the nodes.

What are Types of Network Topologies?

1. Linear Bus Topology

Fig 3.2 : Linear Bus Topology has a backbone, a terminator, and nodes

- 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.

Fig 3.3 : Linear Bus Network Topology

2. Star Topology

Fig 3.4 : Star Topology connects devices using a hub

- A Star network is one of the most common computer network topologies. In its simplest form, a star network consists of one central hub which acts as a conduit to transmit messages. In star topology, every host is connected to a central hub. A star network is an implementation of a spoke–hub distribution paradigm in computer networks. The hub and hosts, and the transmission lines between them, form a graph with the topology of a star. Data on a star network passes through the hub before continuing to its destination. The star topology reduces the impact of a transmission line failure by independently connecting each host to the hub. Each host may thus communicate with all others by transmitting to, and receiving from, the hub. The failure of a transmission line linking any host to the hub will result in the isolation of that host from all others, but the rest of the network will be unaffected.

Fig 3.5 : Star Network Topology

3. Ring Topology

Fig 3.6 : Ring Topology 

- A ring network is a network topology in which each node connects to exactly two other nodes, forming a single continuous pathway for signals through each node - a ring. Data travels from node to node, with each node along the way handling every packet. Rings can be unidirectional, with all traffic travelling either clockwise or anticlockwise around the ring, or bidirectional. Because a unidirectional ring topology provides only one pathway between any two nodes, unidirectional ring networks may be disrupted by the failure of a single link. A node failure or cable break might isolate every node attached to the ring. In response, some ring networks add a "counter-rotating ring" (C-Ring) to form a redundant topology: in the event of a break, data are wrapped back onto the complementary ring before reaching the end of the cable, maintaining a path to every node along the resulting C-Ring.

Fig 3.7 : Ring Network Topology

4. Mesh Topology

Fig 3.8 : Mesh is the best topology to use

-  Mesh network (or simply Meshnet) is a local network topology in which the infrastructure nodes (i.e. bridges, switches and other infrastructure devices) connect directly, dynamically and non-hierarchically to as many other nodes as possible and cooperate with one another to efficiently route data from/to clients. This lack of dependency on one node allows for every node to participate in the relay of information. Mesh networks dynamically self-organize and self-configure, which can reduce installation overhead. The ability to self-configure enables dynamic distribution of workloads, particularly in the event that a few nodes should fail. This in turn contributes to fault-tolerance and reduced maintenance costs. Mesh topology may be contrasted with conventional star/tree local network topologies in which the bridges/switches are directly linked to only a small subset of other bridges/switches, and the links between these infrastructure neighbours are hierarchical.

Fig 3.9 : Mesh Network Topology

5. Hybrid Topology

Fig 3.10 : Linear, Star, and Ring Topologies

- Hybrid topology is an integration of two or more different topologies to form  a resultant topology which has many advantages (as well as disadvantages) of' all the constituent basic topologies rather than having characteristics of' one specific topology. This combination of'topologies is done according to the requirements of' the organization.

Sources : https://en.wikipedia.org/wiki/Network_topology (network topology)https://www.computerhope.com/jargon/l/linear-bus-topology.htm (linear bus topology)https://en.wikipedia.org/wiki/Star_network (star topology)https://en.wikipedia.org/wiki/Ring_network (ring topology)https://en.wikipedia.org/wiki/Mesh_networking (mesh topology)https://blossoms.mit.edu/sites/default/files/video/download/Notes-on-Hybrid-topology.pdf (hybrid)

4 Types of Computer Network

All About Computer Networking

What is the definition of Computer Networks?

- A computer network is a set of computers connected together for the purpose of sharing resources. The most common resource shared today is connection to the Internet. Other shared resources can include a printer or a file server. The Internet itself can be considered a computer network.

4 Types of Computer Network

1. PAN (Personal Area Network)

- is a computer network for interconnecting devices centered on an individual person's workspace. A PAN provides data transmission amongst devices such as computers, smartphones, tablets and personal digital assistants. PAN ranges typically within a range of 10 meters.

- Portable Devices

2. LAN (Local Area Network)

- is a computer network that interconnects computers within a limited area such as a residence, school, laboratory, university campus or office building. LAN is a group of computers and associated devices that share a common communication lines or wireless link to server.

- Room to Room; Building to Building

3. MAN (Metropolitan Area Network)

- is a computer network that interconnects users with computer resources in a geographic area or region. The term is applied to the interconnection of networks in a city into a single larger network. The latter usage is also sometimes referred to as a campus network.

- Town to Town; City to City

4. WAN (Wide Area Network)

- is a telecommunications network or computer network that extends over a large geographical distance/place. Wide area networks are often established with leased telecommunication circuits. Consists of plenty of LANs. 

- Country to Country

Sources : 

https://study.com/academy/lesson/what-is-a-computer-network-types-definition-quiz.html (networks)

https://en.wikipedia.org/wiki/Personal_area_network (pan)

https://en.wikipedia.org/wiki/Local_area_network (lan)

https://en.wikipedia.org/wiki/Metropolitan_area_network (man)

https://en.wikipedia.org/wiki/Wide_area_network (wan)

How to be a Responsible Netizen?

How to be a Responsible Netizen

Some of us nowadays, are prone to computers, they praise their computers too much for surfing, communicating, and playing. Though. computers can be helpful, with our homeworks, projects, and activities. But sometimes, it can be dangerous for children, especially teenagers, it is too risky for their health condition.

Some of us flutz too much infront of our computers, others even stay for hours and days living their lives hailing their computers, becoming introvert or anti-social towards people. It is dangerous for ourselves because it kills us silently, especially our nerves our nerves are connected with the other systems so it can spread faster. Some use it as transaction, cyber-problems, and many more.

On the other hand, it can also help us, like communicating with other people from afar, helping you get through your homeworks, and projects, you can also use it to find friends, surf the internet, and enhance your brain capacity.

Being a netizen is a big responsibility. Therefore we need to use it right. By avoiding all forms of cyber-problems like cyber-bullying, etc. By showing your good netiquette. By posting some inspiring things, so that people will idolize you. By using it often, I'm not against Internet, but it's just that, it is more fun outside the computer, more lively and sociable. By thinking first before clicking, before you share other posts, you need to know the "story-behind" to that, this also includes, all about sharing fake news. By telling the truth about everything. Lastly, by keeping your surroundings safe, you do not post anything that can ruin your life, especially when you tell everything to the person you just met in the internet, it is better to know him first before sharing some part of your life.

Through this, I can inspire people so they can innovate on how to be a responsible or good netizen. And through these words, I can initiate people that it is truly a big responsibility being a netizen, that they may realize that this is not a little thing. 

Yes, computers can be helpful in many ways, but then again, they are also our root of sadness and sorrow, if we use it too much. As they say "Life is as facile as a rose", if you do not take good care of it, it'll wipe out. As Filipino people say, "Ang lahat ng sobra ay nakakasama". If we do this things, we can avoid the illness that we can obtain. Furthermore, "Live your life to the fullest for YOLO, you only live once". Remember, it is better to be a RESPONSIBLE netizen, than an IRRESPONSIBLE one.