Co pa e and contrast classful and classless Compare a d co as c ass u a d c ass ess IP addressing. Review VLSM and explain the benefits of classless IP addressing. Describe the role of the Classless Inter-Domain Inter Domain Routing (CIDR) standard in making efficient use of scarce IPv4 addresses In addition to subnetting, it became possible to summarize a large collection of classful networks into an aggregate route, or supernet. | I11111111 CISCO VLSM and CIDR Routing Protocols and Concepts - Chapter 6 ITE PC Chapter 1 2007 Cisco Systems Inc. All rights reserved. Cisco Public 1 Objectives Compare and contrast classful and classless IP addressing. Review VLSM and explain the benefits of classless IP addressing. Describe the role of the Classless Inter-Domain Routing CIDR standard in making efficient use of scarce IPv4 addresses In addition to subnetting it became possible to summarize a large collection of classful networks into an aggregate route or supernet. ITE PC Chapter 1 2007 Cisco Systems Inc. All rights reserved. Cisco Public 2 Introduction Prior to 1981 IP addresses used only the first 8 bits to specify the network portion of the address In 1981 RFC 791 modified the IPv4 32-bit address to allow for three different classes Class A addresses used 8 bits for the network portion of the address Class B used 16 bits Class C used 24 bits. -This format became known as classful IP addressing. IP address space was depleting rapidly the Internet Engineering Task Force IETF introduced Classless Inter-Domain Routing CIDR -CIDR uses Variable Length Subnet Masking VLSM to help conserve address space. -VLSM is simply subnetting a subnet ITE PC Chapter 1 2007 Cisco Systems Inc. All rights reserved. Cisco Public
