Subnetting (obj 1.7) Flashcards
(11 cards)
What is subnetting?
Involves dividing a large network into smaller networks for better management and optimization
It’s crucial for efficient use of IP addresses, both public and private.
What do subnet masks do?
Modify network sizes by borrowing bits from the host portion and adding them to the network portion
Default classful subnet masks are rarely optimal for network sizes, so custom subnet masks are used for better efficiency.
What is the formula for the number of subnets?
2^S where S is the number of borrowed bits
This formula calculates how many subnets can be created based on the bits borrowed.
How do you calculate assignable IP addresses per subnet?
2^h - 2 where h is the number of host bits
The ‘- 2’ accounts for the network ID and broadcast ID that cannot be assigned to hosts.
What are classful networks?
Networks with fixed sizes (e.g., /8, /16, /24)
Classful networks have predetermined boundaries and do not allow for flexibility in subnetting.
What is the difference between classful and subnetted networks?
Subnetted networks allow flexibility in network size by borrowing bits from the host portion
This flexibility enables more efficient use of IP addresses.
What is CIDR notation?
A shorthand for expressing subnet masks
CIDR consolidates multiple subnets under a single route for more efficient routing.
What does Variable Length Subnet Mask (VLSM) allow?
Allows subnets of various sizes to be used within a larger network
VLSM enhances flexibility in subnetting by accommodating different network requirements.
What should you memorize for subnetting exams?
The chart correlating subnet mask notation (/24, /25, etc.) with the number of subnets and assignable IP addresses
This helps quickly answer subnetting questions by understanding the relationship between subnet size and IP allocation.
Why is it important to practice subnetting problems?
Especially in the Class C range (/24 to /30)
Familiarity with these ranges helps in mastering subnetting calculations.
What should you familiarize yourself with to excel in subnetting questions on exams?
CIDR notation and subnetting calculations
Understanding these concepts is crucial for solving subnetting problems effectively.
