Computer Networking (Part - 2)

Introduction to Network Media, Topology and Protocol

Network Media

Network media refers to the physical infrastructure that carries data communications in a network. It can be either wired or wireless, and different types of media use different methods to transmit data.

Wired media use physical cables to transmit data. Common types of wired media include:

1. Copper cables: These include twisted pair cables and coaxial cables, which are used in many local area networks (LANs) and other networks. Copper cables are relatively inexpensive and provide good performance, but they are prone to interference and are not suitable for long distance communication.

2. Fiber optic cables: These use thin strands of glass or plastic to transmit data as pulses of light. Fiber optic cables are highly resistant to interference and can transmit data over long distances, but they are more expensive than copper cables.

Wireless media use radio frequency (RF) or infrared (IR) signals to transmit data. Some common types of wireless media include:

1. Wi-Fi: This is a wireless networking standard that uses RF signals to transmit data over short distances. It is commonly used to connect devices to the internet in homes and businesses.

2. Bluetooth: This is a wireless technology that uses short-range RF signals to transmit data between devices. It is commonly used to connect devices such as phones, tablets, and computers.

3. Cellular: This refers to the network of cells that transmit data using RF signals. It is used to connect mobile devices such as phones and tablets to the internet.

There are also hybrid media that use a combination of wired and wireless technologies. For example, a wireless access point (WAP) may be used to connect a group of wired devices to a wireless network.

In addition to the type of media used, the data transmission rate, or bandwidth, is also an important consideration when choosing network media. The bandwidth determines how much data can be transmitted in a given time period, and higher bandwidths can support faster data transfer rates.

Network Topologies

Network topology is the way that devices are connected within a computer network. It refers to the layout of the connections between devices, and it can have a significant impact on the performance and reliability of the network.

There are several different types of network topologies, including:

1. Bus topology: In a bus topology, all devices are connected to a single central cable. Data is transmitted along the cable, and all devices can listen and respond to the data. This type of topology is simple and inexpensive, but it can be prone to failure if the central cable is damaged or if there are too many devices connected to it.

2. Ring topology: In a ring topology, devices are connected in a circular arrangement, with each device connected to two other devices. Data is transmitted around the ring in a specific direction, and each device acts as a repeater, forwarding the data to the next device in the ring. This type of topology is reliable, but it can be slow and inflexible, as adding or removing devices requires reconfiguring the entire ring.

3. Star topology: In a star topology, all devices are connected to a central hub. The hub acts as a central point of communication, and all data is transmitted through it. This type of topology is easy to set up and expand, and it is less prone to failure than a bus topology. However, if the central hub fails, the entire network will be down.

4. Mesh topology: In a mesh topology, every device is connected to every other device. This allows for multiple paths between devices, so data can be transmitted along any available route. Mesh topologies are highly reliable, as there are multiple ways for devices to communicate with each other. However, they can be expensive and complex to set up and manage.

There are also hybrid topologies, which combine elements of multiple topologies. For example, a star-ring topology combines elements of both star and ring topologies. The choice of network topology depends on the specific requirements of the network, such as the number of devices, the amount of data that needs to be transmitted, and the level of reliability and fault tolerance that is required.

Network Protocol

A protocol is a set of rules that govern how devices on a network communicate with each other. Protocols define the format of the data being transmitted, as well as the rules for sending and receiving messages.

There are many different types of network protocols, and they can be grouped into several categories:

1. Link layer protocols: These protocols are responsible for transmitting data over a single link between two devices. Examples include Ethernet, which is a common protocol for LANs, and Point-to-Point Protocol (PPP), which is used for dial-up and DSL internet connections.

2. Internet layer protocols: These protocols are responsible for transmitting data between devices on different networks. The most important of these is the Internet Protocol (IP), which defines the format of the data packets used to transmit data over the internet.

3. Transport layer protocols: These protocols are responsible for providing reliable communication between devices. The most commonly used transport protocol is the Transmission Control Protocol (TCP), which provides error checking and retransmission of lost data.

4. Application layer protocols: These protocols define the specific rules for transmitting data used by a particular application or service. Examples include the Hypertext Transfer Protocol (HTTP) used by web browsers to request and receive web pages, and the Simple Mail Transfer Protocol (SMTP) used to send email.

Protocols are important because they allow different devices and systems to communicate with each other, regardless of their underlying hardware or software. They provide a common language that can be used by devices to exchange data and instructions.

Setting Up Microsoft Network

There are several steps you can follow to set up a Microsoft network:

1. Determine your network requirements: Consider the number of devices you will be connecting, the type of network you need (e.g., LAN, WAN, or VPN), and the types of services you will be using (e.g., file sharing, printing, internet access).
   

2. Gather the necessary hardware and software: You will need a router or switch to connect your devices, as well as cables or wireless access points to provide the physical connection. You will also need a copy of the Microsoft operating system (OS) to install on each device, as well as any additional software or services you will be using.

3. Install the Microsoft OS on each device: Follow the instructions provided by Microsoft to install the OS on each device. Make sure to set up any necessary user accounts and permissions.

4. Connect the devices: Use the router or switch to connect your devices according to your chosen topology. If you are using a wired connection, use Ethernet cables to connect the devices to the router or switch. If you are using a wireless connection, use a wireless access point to connect the devices to the network.

5. Configure the network settings: Use the network settings on each device to configure the IP addresses and other network settings. You may need to use a DHCP server to automatically assign IP addresses to the devices.

6. Set up any additional services or applications: Depending on your requirements, you may need to set up additional services or applications, such as file sharing, printing, or internet access. Follow the instructions provided by Microsoft or the relevant software vendors to set up these services.

Once you have completed these steps, your Microsoft network should be up and running. You may need to troubleshoot any issues that arise, but in general, the process of setting up a Microsoft network is fairly straightforward

Dial-Up Networking

Dial-up networking is a method of establishing a network connection using a telephone line. It was commonly used in the past to connect to the internet, but it has largely been replaced by faster and more reliable broadband technologies such as DSL and cable.

To set up a dial-up network connection, you will need a computer with a modem and a phone line. You will also need an account with an internet service provider (ISP) that offers dial-up service.

To establish a connection, you will need to use the dial-up networking software provided by your operating system (OS) to dial the number provided by your ISP. The modem will then send and receive data over the phone line, establishing a connection to the internet.

Dial-up networking is relatively slow, with speeds typically ranging from 56kbps to 128kbps. It is also prone to interference and other issues, such as dropped connections and slow performance. However, it is still used in some areas where broadband services are not available or are too expensive.

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