Download Planning the Addressing Structure

Planning the
Addressing Structure
Working at a Small-to-Medium Business or ISP –
Chapter 4
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Objectives

Describe how IP Addressing is implemented in the
LAN

Subnet a given network to allow for efficient use of IP
address space

Explain how Network Address Translation (NAT) and
Port Address Translation (PAT) are used in a
network
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Running out of Space?
 As we learned in the first course IP addresses are in
short supply due to an initial design that just did not
anticipate the number of Internet users we have today.
 Subnetting, the dividing of a network into smaller
networks, provides us with a short-term solution to the
long-term problem of not enough IP addresses.
 How serious is the problem of not enough addresses?
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Running out of Space?
 China, for example, has fewer addresses than Stanford
University. Why?
When addresses were first being distributed, Stanford
(one of the original universities) kept large numbers for
themselves.
 What will be the long-term solution?
IPv6 - an addressing scheme with 128 bits versus the
current 32-bit addresses we have today. Asia may be
the first continent to adopt IPv6 on a large scale. Asia
has the most severe shortage, a growing population,
and no way to get additional IPv4 addresses.
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And Now for Something Completely
Different!
 Convert these numbers to Decimal
1. 00011011
2. 10101010
3. 01101111
4. 11000000
5. 01010101
6. 00100000
7. 11101101
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IP Addressing Structure
 Practice converting 8-bit binary to decimal
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IP Addressing Structure
 Convert decimal to 8-bit binary
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IP Addressing Structure
 Practice converting decimal to 8-bit binary
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Section 4.1 Implementation of IP Addressing in
the LAN
 Review the purpose of an IP address
 Review IP address hierarchical structure
 Review the classes of IP addresses
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IP Addressing Structure
 Describe the dotted decimal structure of a binary IP
address and label its parts
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IP Addressing Structure
 Describe the general role of 8-bit binary in network
addressing and convert 8-bit binary to decimal
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Classify and Define IPv4 Addresses
 Name the three types of addresses in the network and
describe the purpose of each type
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Classify and Define IPv4 Addresses
 Determine the network, broadcast and host addresses
for a given address and prefix combination
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Classify and Define IPv4 Addresses
 Determine the network, broadcast and host addresses
for a given address and prefix combination
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Classify and Define IPv4 Addresses
 Name the three types of communication in the Network
Layer and describe the characteristics of each type
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Classify and Define IPv4 Addresses
 Define public address and private address
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Classify and Define IPv4 Addresses
 Name the three types of communication in the Network
Layer and describe the characteristics of each type
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Classify and Define IPv4 Addresses
 Identify the historic method for assigning addresses
and the issues associated with the method
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Determine the network portion of the host address and
the role of the subnet mask
 Describe how the subnet mask is used to create and
specify the network and host portions of an IP address
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Determine the network portion of the host address and
the role of the subnet mask
 Use the subnet mask and ANDing process to extract
the network address from the IP address
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Determine the network portion of the host address and
the role of the subnet mask
 Use ANDing logic to determine an outcome
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Determine the network portion of the host address and
the role of the subnet mask
 Observe the steps in the ANDing of an IPv4 host
address and subnet mask
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Calculating Addresses
 Use the subnet mask to divide a network into smaller
networks and describe the implications of dividing
networks for network planners
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Calculating Addresses
 Use the subnet mask to divide a network into smaller
networks and describe the implications of dividing
networks for network planners
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A Subnetting Example
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Implementation of IP Addressing in the LAN
 Describe classful subnetting including how subnet
masks are used in calculations for addressing and
routing, and IP address notation for subnet masks
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Implementation of IP Addressing in the LAN
 Identify the number of subnet bits required for a given
network implementation
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Classless Subnetting
 CIDR
 VLSM
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Creating Custom Subnet Masks
 Communicating between subnets
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Calculating Addresses
 Extract network addresses from host addresses using
the subnet mask
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Assigning Addresses
 Assigning Addresses can help separate functions
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Calculating Addresses
 Calculate the number of hosts in a network range given
an address and subnet mask
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Using Network Address Translation in a
Network
 Describe the purpose and function of network address
translation (NAT) and how it is implemented
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Using Network Address Translation in a
Network
 Define the terms used to describe how packets are
transported across a NAT configuration
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Using Network Address Translation in a
Network
 Compare static and dynamic IP NAT and describe
when each should be used
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Using Network Address Translation in a
Network
 Describe the purpose and function of Port-based
Address Translation (PAT) within a NAT configuration
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Using Network Address Translation in a
Network
 Identify possible issues within a network due to NAT
configuration implementation
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Implementation of IP Addressing in the LAN
 Describe the origin, purpose, and function of IPv6
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Assigning Addresses
 Identify several changes made to the IP protocol in
IPv6 and describe the motivation for migrating from
IPv4 to IPv6
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Summary
 IP addressing can be tailored to the needs of the
network design through the use of custom subnet
masks.
 Classless subnetting gives classful IP addressing
schemes more flexibility through the use of variable
length subnet masks.
 Network Address Translation (NAT) is a way to shield
private addresses from outside users.
 Port Address Translation (PAT) translates multiple local
addresses to a single global IP address, maximizing the
use of both private and public IP addresses.
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