DHCP Explained: How It Works and What to Look For
DHCP supplies hosts with IP configuration and leases.
Published by Protocol Explorer · Reviewed
How DHCP works
A common initial exchange is DISCOVER, OFFER, REQUEST and ACK. The server grants a lease with configuration such as an address and possibly router or DNS settings.
What to look for in an exchange
Compare transaction IDs and message types. A lease expires or is renewed; not every DHCP exchange follows the initial four-message pattern.
Follow an example step by step
- Identify the client transaction ID and its DISCOVER message.
- Follow the OFFER and client REQUEST, then match the server ACK to the same transaction.
- Read the assigned address, lease duration and configuration options offered by the server.
Common interpretation mistake
A DHCP offer is not itself proof that the client completed configuration; look for the rest of the exchange.
Key point to remember
Renewal and rebinding are different states and need not repeat the initial broadcast sequence.
Explore the protocol
The DHCP overview is free without an account. Its full interactive lesson is included in Protocol Explorer Pro, a one-time $4.99 purchase; an account is required to buy Pro and restore the licence across devices.
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Specification
Read the primary specification for DHCP for the authoritative protocol details. The interactive scenario is a simplified teaching model, not a capture of your network.
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