Which of the following statements about IP route summarization is FALSE?

IP route summarization, also known as route aggregation or supernetting, is the process of combining multiple contiguous IP network prefixes into a single, more general prefix advertisement. This is done to reduce the number of routes in routing tables across a network. The statement in option A describes subnetting, which is the inverse process of dividing a large, contiguous IP address block into multiple smaller, more specific sub-networks. Therefore, the statement is false as it misrepresents the function of route summarization.

B. Summarization's primary purpose is to advertise one route instead of many, which directly reduces the size of routing tables on downstream routers.
C. By reducing routing table size and the amount of routing protocol traffic, summarization decreases router processing load, thus improving network scalability.
D. Summarization contains the advertisement of individual link failures. If a specific subnet within a summary flaps, the change is not propagated as long as the summary route remains valid.

1. Nokia 7750 SR OS R19.10.R1 OSPF and IS-IS Guide: In the "OSPF Route Summarization" section, it states, "Route summarization is the consolidation of multiple routes into a single advertisement. This is done at the area border routers (ABRs)... Summarization reduces the amount of routing information that is advertised between areas..." This supports that summarization combines routes (opposite of A) and reduces routing table size (B), which improves scalability (C) and stability (D). (Reference to general concept within OSPF configuration).

2. Nokia SRC-PE (Policy Engine) 12.0 CDRouter Guide, Section: Route Aggregation: "Route aggregation (also called route summarization or supernetting) is a method to minimize the number of routing tables in an IP network. It works by consolidating selected multiple routes into a single route advertisement." This definition directly contradicts option A and supports option B.

3. Kurose, J. F., & Ross, K. W. (2017). Computer Networking: A Top-Down Approach (7th ed.). Pearson. Chapter 5, Section 5.2.3, "The Internet Control Message Protocol (ICMP)," and related routing protocol sections describe how route aggregation (summarization) is a key technique for achieving scalability in the Internet. It explicitly states that aggregation combines prefixes to reduce the size of forwarding tables in routers. This supports options B and C.