Antwort mit KI erzeugt
Subnet Allocation Problem
In this problem, we are given a major network \(123.456.0.0/16\), and we need to allocate subnets to four customers A, B, C, and D with specified address requirements. The main objective is to fulfill each customer's address requirements while using minimal-sized subnets.
Step-by-step Solution:
1.
Determine the smallest power of 2 greater than or equal to each customer's address requirement:
- For Customer A (4000 addresses): \(2^{12} = 4096\) addresses
- For Customer B (7000 addresses): \(2^{13} = 8192\) addresses
- For Customer C (9000 addresses): \(2^{14} = 16384\) addresses
- For Customer D (2500 addresses): \(2^{12} = 4096\) addresses
2.
Determine the subnet mask for the required addresses:
The number of addresses needed determines the subnet mask:
\(
\text{Subnet Mask} = 32 - \log_2 (\text{Number of addresses})
\)
- For Customer A: 4096 addresses means \(2^{12}\), hence \(32 - 12 = 20\) => Subnet mask /20
- For Customer B: 8192 addresses means \(2^{13}\), hence \(32 - 13 = 19\) => Subnet mask /19
- For Customer C: 16384 addresses means \(2^{14}\), hence \(32 - 14 = 18\) => Subnet mask /18
- For Customer D: 4096 addresses means \(2^{12}\), hence \(32 - 12 = 20\) => Subnet mask /20
3.
Allocate the subnets from the major network:
- Major network: \(123.456.0.0/16\)
Start allocating from the beginning of the address space, ensuring that each subnet allocation fits within the original /16 network and does not overlap with the previous allocations:
- Customer C (/18): Largest at first: \(123.456.0.0/18\) (16,384 addresses)
- Customer B (/19): Second largest: \(123.456.64.0/19\) (8,192 addresses)
- Customer A (/20): Next: \(123.456.96.0/20\) (4,096 addresses)
- Customer D (/20): Last: \(123.456.112.0/20\) (4,096 addresses)
4.
Calculate remaining address space:
- Originally available addresses in /16: \(2^{16} = 65,536\)
- Allocated:
\(
2^{14} (= 16,384) \text{ (Customer C)} + 2^{13} (= 8,192) \text{ (Customer B)} + 2^{12} (= 4,096) \text{ (Customer A)} + 2^{12} (= 4,096) \text{ (Customer D)}
\)
- Total allocated addresses: \(16384 + 8192 + 4096 + 4096 = 32768\)
- Remaining unallocated addresses:
\(
65536 - 32768 = 32768
\)
Summary
-
Customer A: \(123.456.96.0/20\) (4096 addresses)
-
Customer B: \(123.456.64.0/19\) (8192 addresses)
-
Customer C: \(123.456.0.0/18\) (16384 addresses)
-
Customer D: \(123.456.112.0/20\) (4096 addresses)
-
Remaining Address Block: \(123.456.128.0/17\) (32,768 addresses)
This allocation ensures that each customer receives the required number of IP addresses and the addresses are allocated as efficiently as possible, leaving a substantial block unallocated.
