https://www.manning.com/livevideo/ccna-exam-part-2-routing-fundamentals-and-subnetting
In this eight-part course you will learn the fundamentals of networking to pass the Cisco Certified Network Associate (CCNA) exam.
ccnaexampartroutingfundamentals
https://www.itpro.com/network-internet/31770/what-is-subnetting
Knowing what subnetting is and when to use it can boost network efficiency
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https://www.nybi.org/subnet-1.php
Free online subnetting questions.
subnettingquiz
https://www.ccnaacademy.com/2022/12/subnetting.html
A subnetwork or subnet is a logical subdivision of an IP network. The practice of dividing a network into two or more networks is called subnetting. C
subnetting
https://subnettingpractice.com/
The most extensive subnetting practice site on the Internet. The best place to practice for your networking career and the CCNA and Network+.
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