An Internet Service Provider (ISP) has the following chunk of CIDR-based IP addresses available with it: 245.248.128.0/20. The ISP wants to give half of this chunk of addresses to Organization A, and a quarter to Organization B, while retaining the remaining with itself. Which of the following is a valid allocation of addresses to A and B?

An Internet Service Provider (ISP) has the following chunk of CIDR-based IP addresses available with it: 245.248.128.0/20. The ISP wants to give half of this chunk of addresses to Organization A, and a quarter to Organization B, while retaining the remaining with itself. Which of the following is a valid allocation of addresses to A and B? Correct Answer 245.248.136.0/21 and 245.248.128.0/22

The correct answer is Option 1.

Key Points

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Since Half of 4096 post addresses must be given organization A, we can set the 12th bit to 1, include that bit into the network path of organization A. So the valid allocation of address to A is 245.248.136.0/21.

The 12th bit is set to 0, but we need only half of the 2048 address, 13th bit can be set to be 0 addresses to B is 245.248.128.0/22.

Hence the correct answer is 245.248.136.0/21 and 245.248.128.0/22.

Related Questions

In each question below is given a statement numbered I, II and III. An assumption is something supposed or taken for granted. You have to consider the following assumption and decide which of the assumption is implicit in the statement. Statement: The June 2018 quarter results of Infosys reflect that the investors waiting for the company to perform as good, if not better, than its largest peer Tata Consultancy Services (TCS) may have to wait a little longer. Infosys, the country’s second-largest software exporter reported slower sequential growth in revenue and profit than TCS for the June quarter (Q1). It also lagged on the fronts of employee attrition and growth in the banking, financial services, and insurance (BFSI) vertical.  Assumptions: I. On the positive side, Infosys continued to add large clients – four in the above $100-million billing category compared with the previous quarter. It continued to retain guidance of 6-8% revenue growth for FY19 while retaining the operating margin band of 22-24%. II. In the near term, the stock performance of TCS is likely to overshadow Infosys given the difference in their growth trajectories. III. The growth momentum of Infosys has slowed relative to TCS. The year-on-year growth in trailing 12-month (TTM) revenue of Infosys in each of the four quarters up to the June 2018 quarter has lagged TCS after leading in the previous five quarters.