Subnetting Flashcards
What is a subnet?
A subnet is a subdivision of a larger network, capable of operating as an independent WAN or LAN.
What parts make up a typical IP address?
Network ID: Identifies the overall network (e.g., 137.207.0.0).
Host ID: Identifies a specific machine within the network (e.g., 0.0.32.2).
How does subnetting modify an IP address?
Part of the Host ID is used to represent the Subnet ID, dividing the network into smaller sub-networks.
How do you create 4 subnets from a Class B address?
Use 2 bits from the host portion. This results in 18 bits for the subnet (16 for the network + 2 for the subnet).
What is the role of internal and external routers in subnetting?
External Routers: Subnetting is transparent and not processed.
Internal Routers: Use the Subnet ID to determine the correct route within the network.
What is multi-level subnetting?
Subnets are further divided into sub-subnets, creating hierarchical layers, with additional host bits used at each level.
How is a Subnet ID calculated?
By using a subnet mask, which divides the network and host portions of an IP address.
What are standard subnet masks for Classes A, B, and C?
Class A: 255.0.0.0.
Class B: 255.255.0.0.
Class C: 255.255.255.0.
What does the subnet mask 255.255.192.0 represent?
It is a non-standard mask, where 192 (binary: 11000000) divides the host portion further for subnetting.
Give examples of common subnet masks for Class B networks.
255.255.192.0 (/18): 4 subnets.
255.255.240.0 (/20): 16 subnets.
255.255.252.0 (/22): 64 subnets.
What is CIDR Notation?
A method to represent subnet masks using the format <IP>/<Number>.</Number></IP>
Provide examples of CIDR Notation.
137.207.32.2/16: Class B address with 16 bits for the network portion.
24.1.2.3/8: Class A address with 8 bits for the network portion.
137.207.177.81/20: Combines 16 bits for the network ID and 4 bits for subnetting.
