This document discusses DHCP (Dynamic Host Configuration Protocol). It describes DHCP's function of automated IP address assignment and allowing clients to obtain configuration information quickly. It outlines DHCP modes including manual assignment of static addresses, automatic assignment of static addresses, and automatic distribution of dynamic addresses. It also describes DHCP states a client can be in like initialize, select, request, bound, renew, and rebind. Key DHCP messages are discussed like discover, offer, request, and acknowledgment. Limitations of dynamic address assignment are also noted.

1. DHCP
NAJIRA SALAM
S1-CNS
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2. TABLE OF CONTENTS
• INTRODUCTION
• DHCP MODES
• ALGORITHM OF DYNAMIC ADDRESS ASSIGNMENT
• DHCP STATES
• DHCP MESSAGES
• LIMITATIONS OF DYNAMIC ADDRESS ASSIGNMENT
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3. INTRODUCTION
• Dynamic host configuration protocol.
• Function is to handle automated address
assignment.
• Allows to acquire configuration information.
• Allows to obtain IP address quickly and
dynamically.
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4. DHCP MODES
• Manual assignment of static addresses
• Automatic assignment of static addresses
• Automatic distribution of dynamic addresses
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5. MANUAL CONFIGURATION
• Administrator provides the pool of available
addresses.
• Supplies server with information to map IP
address to physical address.
• A manager can configure specific address for a
specific computer.
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6. AUTOMATIC CONFIGURATION
• No participation for administrator.
• DHCP server arbitrarily chooses an IP address
for the client.
• Address chosen from the pool of available
address.
• Constant mapping between clients IP address
and identifying information.
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7. DYNAMIC CONFIGURATION
• Assigns IP address for limited time-lease
duration.
• Allows future reuse of released address.
• Building of IP address in which number of nodes
exceeds number of available IP address.
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8. ALGORITHM OF DYNAMIC ADDRESS
ASSIGNMENT
• Administrator controls network configuration.
• Two parameters-
pool of address available
Lease duration
• Server must be within the same subnet as
clients.
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9. METHODS OF MUTUAL DISPOSITION
OF DHCP CLIENTS AND SERVERS
• Network 1- A redundant DHCP server in
network.
• Network 2- Server is replaced by a relay agent.
• Network 3- Redirects to server located in
another subnet.
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10. METHODS OF MUTUAL DISPOSITION
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11. DHCP STATES
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12. • INITIALIZE
• SELECT
• REQUEST
• BOUND
• RENEW
• REBIND
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13. DHCP MESSAGES
• DHCP discover-client broadcast this message.
• DHCP offer-servers respond using this message.
• DHCP request-information about server whose
offer has accepted.
• DHCP acknowledgment-server respond using
this message.
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14. LIMITATIONS OF DYNAMIC ADDRESS
ASSIGNMENT
• Translating domain name to IP address.
• Remote control and automatic monitoring.
• Packet filtering by IP address.
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