Networking Tips


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Reference: Cisco: Internetworking Basics



IP addresses are divided into address classes that broadly allocate groups of IP addresses, so that an address that begins with the byte 191, for example, belongs to a class B network. CIDR is no addressing problems such as class B exhaustion by grouping contiguous class C addresses into a single network allocation.

IP Address Classes

IP Address Classes
Class Address Range Allocation
Class A 1-126.xx.xx.xx 16 million host network
Class B 128-191.xx.xx.xx 65536 host network
Class C 192-223.xx.xx.xx 256 host network
Class D 224-239.xx.xx.xx multicast
Class E 240-255.xx.xx.xx reserved

About the Author

Jeffrey Hunter is an Oracle Certified Professional, Java Development Certified Professional, Author, and an Oracle ACE. Jeff currently works as a Senior Database Administrator for The DBA Zone, Inc. located in Pittsburgh, Pennsylvania. His work includes advanced performance tuning, Java and PL/SQL programming, developing high availability solutions, capacity planning, database security, and physical / logical database design in a UNIX / Linux server environment. Jeff's other interests include mathematical encryption theory, tutoring advanced mathematics, programming language processors (compilers and interpreters) in Java and C, LDAP, writing web-based database administration tools, and of course Linux. He has been a Sr. Database Administrator and Software Engineer for over 20 years and maintains his own website site at: Jeff graduated from Stanislaus State University in Turlock, California, with a Bachelor's degree in Computer Science and Mathematics.

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