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Day 21. Networking Fundamentals > Network Topologies - Pg. 83

Day 21 83 Really Big Numbers All the addressing and subnet masks we have used so far are called Internet Protocol Version 4 (IPv4). It contains 2 to the 32 total number of addresses. In other words, these are 128-bit address- es. That is pretty big number, right? You better sit down. We are moving to IPv6 with 2 to the 128 number of addresses. Now that is a big number. The A+ exam asks you to identify valid IPv6 addresses only. More if-thens: If the number contains groups of four hexadecimal digits (0­9 and a­f) separated by colons, then it is probably a valid IPv6 address. If there is only one instance of a double colon (::), then it is probably a valid IPv6 address. If the number contains any letter besides a­f or has more than one double colon, then it is probably not a valid IPv6 address. If you're taking your career seriously, then you will not let fear of really big numbers limit you. If you still do not understand IP addressing, subnet masks, or how to identify a valid IPv6, then do not give up. Own your learning and get on Google, ask current geeks, ask your teacher, ask your friends. This number stuff is really important.