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Addressing the Network – IPv4

Network Fundamentals – Chapter 6

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Assigning Addresses Structured process to assign IP addresses to

hosts..why?

•Preventing duplication of addresses

• Each host in an internetwork must have a unique address

•Providing and controlling access

• Some hosts, such as servers, provide resources to the internal network as well as to the external network

•Monitoring security and performance

• identify the device on the network that has a problematic address.

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Assigning Addresses End user devices can obtain addresses either statically

through an administrator or dynamically through DHCP

Static

With a static assignment, the network administrator must manually configure the network information for a host. At a minimum, this includes entering the host IP address, subnet mask, and default gateway.

Dynamic

DHCP enables the automatic assignment of addressing information such as IP address, subnet mask, default gateway, and other configuration information.

The configuration of the DHCP server requires that a block of addresses, called an address pool, be defined to be assigned to the DHCP clients on a network.

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Assigning Addresses

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Assigning Addresses Internet Assigned Numbers Authority

(IANA)

IANA (http://www.iana.net) is the master holder of the IP addresses. The IP multicast addresses and the IPv6 addresses are obtained directly from IANA

IANA allocated IPv4 address space to various other registries to manage for particular purposes or for regional areas. These registration companies are called Regional Internet Registries (RIR).

The following are the major registries:

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IPv6 IPv6 creating expanded addressing capabilities was the initial

motivation for developing this new protocol. Other issues were also considered during the development of IPv6, such as these:

• Improved packet handling

• Increased scalability and longevity

• Quality of service (QoS) mechanisms

• Integrated security

To provide these features, IPv6 offers the following:

128-bit hierarchical addressing to expand addressing capabilities

Header format simplification to improve packet handling

Improved support for extensions and options for increased scalability/longevity and improved packet handling

Flow-labeling capabilities as QoS mechanisms

Authentication and privacy capabilities to integrate security

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Assigning Addresses IPv6

4x4x8

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Subnet

Subnetting allows creating multiple logical networks from a single address block.

27 -128

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Subnet

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Subnet

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Subnet mask

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Testing the Network Layer Ping command can be used to determine if the IP

protocol is operational on a local host

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Testing the Network Layer Ping can be used to verify that a local host can

communicate with a gateway across a local area network

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Testing the Network Layer Ping can be used to verify that a local host can

communicate via a gateway to a device in remote network

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Testing the Network Layer Ping can be used to verify that a local host can

communicate via a gateway to a device in remote network

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Testing the Network Layer Tracert / traceroute can be used to observe the path

between two devices as they communicate and trace the steps of tracert / traceroute's operation

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Testing the Network Layer Tracert/traceroute can be used to observe the path

between two devices as they communicate and trace the steps of tracert/traceroute's operation

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Summary

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