Lesson 5C Flashcards
What is a VLAN?
A VLAN (Virtual LAN) is a way to create separate groups within a single switch. Each VLAN acts like its own small network, so devices in different VLANs don’t mix their messages, even if they are on the same physical switch.
How does a VLAN help with network performance?
VLANs reduce network congestion by splitting a large network into smaller, manageable sections. Each VLAN has its own broadcast domain, which means broadcast messages only go to devices in the same VLAN, not all devices on the switch.
What is a subnet?
A subnet is a smaller, separate network within a larger network. It divides the main network into smaller sections, each with its own unique range of IP addresses. This helps organize and manage the network more efficiently.
What is classful addressing?
Classful addressing is an old method of assigning IP addresses based on address ranges:
Class A: For very large networks with up to 16 million devices.
Class B: For medium-sized networks with up to 65,000 devices.
Class C: For smaller networks with up to 254 devices.
How do you identify an IP address class?
Check the first number of the IP address:
1 to 126: Class A
128 to 191: Class B
192 to 223: Class C
What is a public IP address?
A public IP address is an address that can be used to reach a device over the internet. It is unique across the entire internet and allows devices to communicate with each other globally.
What is a private IP address?
A private IP address is used within a local network (like home Wi-Fi) and is not visible on the internet. It allows devices to communicate within the same network without using up public IP addresses.
What does NAT do?
NAT (Network Address Translation) changes private IP addresses to a public IP address when sending data to the internet. It allows multiple devices on a local network to share a single public IP address.
What is a proxy server?
A proxy server is an intermediary that retrieves data from the internet on behalf of a device. It has a public IP address and can provide privacy and control over internet usage by acting as a go-between.
What is APIPA?
APIPA (Automatic Private IP Addressing) is used when a device can’t find a DHCP server to get an IP address. It automatically assigns an address in the range 169.254.1.1 to 169.254.254.254 so the device can still communicate on the local network.
What does APIPA stand for and what does it do when a computer can’t find a DHCP server?
APIPA stands for Automatic Private IP Addressing. When a computer can’t find a DHCP server, it automatically assigns itself an IP address from the range 169.254.1.1 to 169.254.254.254. This allows the computer to still communicate with other devices on the same local network even though it can’t connect to the internet.
What are two important factors to consider when planning an IPv4 network addressing scheme?
1) Number of Subnets: Decide how many smaller networks (subnets) you need.
2) Number of Hosts: Determine how many devices (hosts) each subnet must support.
From which ranges should your network ID be chosen, and which ranges should be avoided?
Your network ID should come from a valid public IP address range or a private IP address range. Avoid using IP ranges reserved for loopback addresses, link-local addresses, multicast addresses, or experimental addresses.
Why is it important that network and host IDs cannot be all 1s or all 0s in binary?
All 1s in binary are reserved for broadcast messages that go to all devices on the network. All 0s are used to represent “this network,” so they cannot be assigned to individual devices.
How do you determine the number of bits to add to your subnet mask if you need a specific number of subnets?
Find the nearest power of 2 that is equal to or greater than the number of subnets you need. For example, if you need 12 subnets, the next power of 2 is 16. This means you need to add 4 bits to your default subnet mask.
