Networking Fundamentals

Question 1

What do the following devices do? Routers, Switches, Modems, NICs, Access Points and Firewalls?

Answer 1

• Routers are devices that interconnect networks together and forwards network traffic between these networks.
• Swtiches are devices that forward data to devices within a LAN.
• Modems are devices that modulate and demodulate signals enabling communication over cable or telephone lines; ISP provides connection via these devices.
• NICS are hardware components that are able to provide a device with a connection to a network.
• Access Points are devices that create a wireless network which device connect to via wireless signals and in turn the wireless network connects to a LAN.
• Firewall is a device or software application that monitors and filters out incoming and outgoing network traffic to the LAN based on security rules or configurations.

Question 2

What is a computer network? What is a LAN and WAN?

Answer 2

• Computer network is complex system that interconnects devices with each other in a certain area or across the globe.
• LAN is a network that connects devices in a small area such as an office, home or multiple offices within close proximity.
• WAN is a network that connects devices across a large area, often connecting multiple LANs together. Often connects devices from city to city.

Question 3

Whats the difference between wired and wireless networks? What are strengths and weaknesses of both?

Answer 3

• Wired Networks often use physical components such as cables (RJ-45) to connect devices to a network and enable data transmission. Offers consistent and stable throughput and depending on shielding within offers protection against interefence.
• Wireless Networks use wireless signals to connect devices to a wireless network (wifi) which in turn connects to a LAN. Offers greater mobility for users but is often susceptible to interfence and often slower throughput than wired networks.

Question 4

What is TCP and IP? What’s the difference between the two?

Answer 4

• TCP is a protocol that connects two nodes together and ensures that data is transmitted reliably from one node to another.
• IP or internet protcol is responsible for data transmission between a source and destination device between networks. Does not guarantee delivery but offers best effort for delivery.

Question 5

What’s the difference between IP addresses and a MAC address?

Answer 5

• IP address is a unique numeric identifier provided to devices once they are connected to a network. Used in data transmission for devices between networks.
• MAC address is a unique numeric identifier that is encoded into a NIC by manufacturer. Enables data transmission between devices within a LAN.

Question 6

What role do MAC addresses? Address Resolution Protocol? and Switching play within LAN communications?

Answer 6

• MAC addresses within NIC enable nodes to be connected within a LAN, data can be transmitted between MAC addresses.
• ARP is used to identify a MAC address from a particular IP address by end devices within a LAN.
• Switches forwards data to devices that are connected to it, more specifically to a nodes MAC address.

Question 7

What role do IP addresses and Routing play in WAN communications?

Answer 7

• IP addresses are unique numeric identifiers that are assigned to devices once connected to a network.
• Routing is the transmission of data packets from source IP address to destination IP address by a router. Router determines the best path for forwarding data by consulting its routing table.

Question 8

What’s the difference between HTTP and HTTPS? Why is HTTPS better than HTTP?

Answer 8

• HTTP is a protocol that enables to access content of a website within a website server via URL entry.
• HTTPS is a secure version of HTTP that contains SSL and TLS encryption to establish a conenction between client and server, once that is done encryption keys will be exchanged to ensure that transmitted data is secured and not susceptible to eavesdroppers and unauthorised access.

Question 9

What’s DNS?

Answer 9

Is the conversion of a domain name (website name) to an IP address.

Question 10

What’s the difference between POP3, IMAP and SMTP email protocols?

Answer 10

• POP3 eliminates the email from the server once it has been accesed by the client.
• IMAP keeps emails stored in the email servers enabling multiple devices to access and manage emails in synchronization.
• SMTP transfers emails from one email server to recipient email server which can then be accessed by recipient.