In the technological era, computer networks are everywhere. You will find them in homes, offices, factories, hospitals, leisure centres etc. In this Blog, you will learn the essential networking technologies, terms and concepts used in all types of wired and wireless networks, home and office.
Home and Office Networks
Your network at home uses the same networking technologies, protocols and services used in large corporate networks and on the Internet. The only difference between a home network and an extensive corporate network is the size. A home network will have between 1 and 20 devices, and a corporate network will have many thousands. If you are entirely new to networking, the introductory course will introduce you to the fundamental networking protocols used in small home/office networks and on the Internet. Setting up and building a home network will introduce some essential networking components and show you how to build a home network and connect it to the Internet.
Networking Types and Structures
Wired vs Wireless Networks
In early 2008 networks were mainly wired. Today, most networks will use a mixture of wired and wireless networks. Wired networks use Ethernet as the data link protocol. This is unlikely to change with the IoT, as IoT devices will be primarily wireless.
Advantages:
- Ethernet ports are found on almost all laptops/PCs and netbooks, even those eight years old.
- Wired networks are faster than Wireless. Data rates were periodically increased from the original ten megabits per second to 1gigabits per second. Most home networks use 10-100Mbps.
- More secure than wireless
Disadvantages
- Need to Use a cable which can be unsightly, difficult to run and expensive.
- It can’t be used easily between buildings.
- Note a new technology that uses mains cable overcomes many of these disadvantages.
- Not supported on Mobile phones and tablets.
On the other hand, Wireless networks use Wi-fi as the data link protocol. However, other wireless options are being developed for the IoT (Internet of things). Below are the advantages and disadvantages of wireless networks –
Advantages
- Generally easier to set up.
- It can be used both on home and public networks
- No cables are required.
- It can be used with mobile phones and tablets.
Wireless Networks Disadvantages
- Generally Slower than wired networks.
- Limited by range.
- Open to eavesdropping.
- Not as secure, depending on the setup.
Networking Topologies and Layout
There are many ways network nodes can be connected. This isn’t usually a consideration in small networks, but it becomes more critical as they get larger. There are many ways network nodes can be connected. Standard connection technologies like Wi-Fi, Bluetooth etc., are designed to work using particular network topology. When designing networks and choosing connection protocols, understanding these topologies is essential. Common are Bus, Ring, Mesh, Star, and Hybrid. Each of these topologies has advantages and disadvantages. Early Ethernet networks used a bus structure; modern Ethernet networks and Wi-Fi networks use a star bus (hybrid) structure. However, both Wi-Fi and Bluetooth are being upgraded to support mesh networking.
Networking Topology- Physical vs Logical
How the nodes communicate with each other can be very different. Most Home and small office networks use a physical bus topology. Common logical typologies are Peer to Peer and Client Server. The web (WWW) is a client-server network at the logical level.
Peer to Peer
in a peer-to-peer network, all nodes are equal, and any node can talk to any other node. No node has any particular role. This was the original networking model of windows networking. (windows for Workgroups)- Diagram below:
Advantages:
- Easier to setup
- Not dependent on a single node
- More resilient
- Better distribution of network traffic
- No central administrator required
- Less expensive hardware required
Disadvantages:
- Less secure and more difficult to secure
- More difficult to administer
- More difficult to backup
- More difficult to locate information.
This was the original networking model used in early Windows networks (windows for Workgroups). A Modern example of Peer to Peer networking is BitTorrent. Although this networking model isn’t currently popular, it could become more popular with the Internet of things (IoT).
Client Server
In a Client-Server network, a server has a unique role, e.g. file server, domain controller, web server etc. A client connects to a server to use the appropriate services. This is the networking model used on the web and the Internet and modern large Windows networks.-Diagram below:
Advantages:
- Easy to find resources as they are on a dedicated node, i.e. A server
- Easy to secure
- Easy to administer
- Easy to backup
Disadvantages:
- Servers are a single point of failure
- Expensive hardware required
- Network traffic gets concentrated
A Modern Example of Client-Server networking is the Web. Facebook, Twitter, Google search and many other web services use this networking model.
Network Size
Networks vary considerably in size. The following are commonly used terms:
- PAN -Personal Area Network – Linking local devices, e.g. PC to the printer
- LAN – Local Area Network- links devices in an office or offices
- MAN – Metropolitan Area network – links devices across multiple buildings like a campus
- WAN – Wide area network – links devices across a country/country.
Networking Levels and Layers and Protocols
A protocol defines a set of rules that govern how computers talk to each other. Ethernet and Wi-Fi are Data link protocols responsible for framing data on the media (cable or wireless). Users can use them for carrying higher-level protocols (IP etc.). Ethernet and Wi-Fi use a physical level address known as the MAC address which is 48 bits. EUI 64 addresses are MAC addresses, with 64 bits that will replace MAC addresses on IPV6. You can divide networking into distinct levels or layers. Each group or layer is responsible for a particular function. The OSI uses a seven-layer model, and TCP/IP networks use a four-layer model. Because TCP/IP networks are the most common, the TCP/IP model is the most important one to understand. The levels are:
- Data link level – e.g. Ethernet, Wi-Fi
- Networking, e.g. IP,
- Transport level, e.g.TCP, UDP
- Application level – e.g. HTTP
What Is An IP Address?
Every device is attached to a network, and the Internet has an IP address. An Internet Protocol address (IP address) is a numerical label assigned to each device (e.g., computer, printer) participating in a computer network that uses the Internet Protocol for communication. There are two versions of IP, they are IPv4 and IPv6. IPv4 has been in use since the start of the Internet and is deployed across the Internet and home/corporate networks. IPv4 uses 32 bits for addressing; however, due to the rapid growth of the Internet, all IPv4 addresses have been allocated. Techniques like NAT (Network Address Translation) have extended the life of IPv4 by allowing the use of private IP addresses inside networks. However, IPv4 will eventually be replaced by IPV6, which uses 128 bits for the address and can accommodate many more hosts (computers/devices). The rollout of IPv6 across the Internet is happening slowly, and IPv4 will be with us for many years, especially in home and small office networks. As IP6 rolls out, they will also need to operate with two addresses until the migration is complete and IP4 is discontinued. IP addresses are logical addresses assigned by a network administrator or can be auto-assigned using DHCP. The critical thing to note is that the IP address of a device isn’t fixed.
Public and Private IP Addresses
Both IPv4 and IPV6 have both public and private address ranges. The personal addresses are used for home/business networks, and the lessons aren’t routable on the Internet, i.e. they don’t travel across the internet. For IP4, the private addresses start with 10. or 192.168. or 172.16. Public lectures are reachable from anywhere on the internet and are routable.
IP Address Assignment
Most modern networks use automatic IP address assignment via DHCP, with manual selection only done in exceptional cases. For home networks, the Internet router or hub usually provides DHCP services for the web. For more extensive networks, a dedicated DHCP server is generally used. Most windows machines will auto-assign their address if they fail to find a DHCP server.
