CompTIA Network+ Practice Test 2026 - Free Network+ Practice Questions and Exam Prep Guide

CIDR (Classless Inter-Domain Routing) block notation contributes to efficient allocation of IP addresses by allowing for more flexible subdivision of IP address space compared to traditional classful addressing. It enables networks to specify subnet masks in a more precise way through the use of a suffix that indicates the number of bits used for the network portion of the address. This flexibility reduces wasted IP addresses in subnets, allowing organizations to assign IP ranges according to their actual needs rather than being constrained to fixed class sizes.

Using CIDR, network administrators can aggregate routes, which leads to a smaller and more manageable routing table on routers, making routing more efficient and conserving IP address space. This is especially important given the limited availability of IPv4 addresses. CIDR also facilitates easier network management and supports more hierarchical and scalable network architectures, making it essential in modern Internet routing practices.