Question

Compare NAT and DHCP. Both can solve the problem of a shortage of addresses in an organization, but by using different strategies. Then, Assume an ISP is granted the block 80.70.56.0/21. The ISP needs to allocate addresses for two organizations each with 500 addresses, two organizations each with 250 addresses, and three organizations each with 50 addresses. a. Find the number and range of addresses in the ISP block. b. Find the range of addresses for each organization and the range of unallocated addresses. c. Show the outline of the address distribution and the forwarding table.

Answer 1

NAT translates private IP addresses to public ones, conserving IPv4 addresses, while DHCP assigns dynamic IP addresses within a network. The ISP block 80.70.56.0/21 encompasses 2048 addresses, which are subdivided into specific CIDR blocks for each organization according to their needs, with a range of unallocated addresses remaining.

Step-by-step explanation:

Comparison of NAT and DHCP-

NAT (Network Address Translation) and DHCP (Dynamic Host Configuration Protocol) are both important mechanisms used to manage IP addresses in networked environments. NAT is used to convert private IP addresses to public IP addresses and vice versa, allowing multiple devices on a local network to share a single public IP address. This helps to conserve the limited number of IPv4 addresses available. On the other hand, DHCP is a protocol that dynamically assigns IP addresses to devices on a network, ensuring that each device has a unique IP address and can communicate on the network efficiently without manual configuration.

Address Allocation for the ISP Block-

An ISP block of 80.70.56.0/21 contains a total of 2048 IP addresses (2^11), ranging from 80.70.56.0 to 80.70.63.255. To allocate addresses to the organizations:

1. Organization 1: 500 addresses, 80.70.56.0/23 (512 addresses)
2. Organization 2: 500 addresses, 80.70.58.0/23 (512 addresses)
3. Organization 3: 250 addresses, 80.70.60.0/24 (256 addresses)
4. Organization 4: 250 addresses, 80.70.61.0/24 (256 addresses)
5. Organization 5: 50 addresses, 80.70.62.0/26 (64 addresses)
6. Organization 6: 50 addresses, 80.70.62.64/26 (64 addresses)
7. Organization 7: 50 addresses, 80.70.62.128/26 (64 addresses)

The unallocated range is: 80.70.62.192/26 - 80.70.63.255 (192 + 256 = 448 addresses).

Address Distribution and Forwarding Table-

The address distribution would allocate specific CIDR blocks to each organization based on their size requirements. The forwarding table would outline the routing paths packets would take based on their destination address, ensuring they are correctly directed to the assigned organization's network.