Why is dhcp request broadcast

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Community Bot 1. But that could have been done by multicasting to those DHCP servers. Why broadcast everyone for it? A multicast response would be assuming the servers are listening for a multicast group address, which isn't part of the standard. I would guess that broadcasting is less complex and therefore more reliable, even if it is noisier. Further, consider the case where DHCP relays are used. The router would have to be 'DHCP multicast' aware, adding an additional dependency into the network.

The DHCP relay function could've been designed this way, but it's possible that mandating multicast support for something as basic as DHCP creates unnecessary overhead.

Zac67 Zac67 YLearn YLearn Why would that imply that broadcast would need to be used? The reason for the broadcast is to let other DHCP servers if any know that the client is declining their offers.

You can source a L3 broadcast from 0. In many instances, the client will get the same address but may not. The lease time defines how long the client can use the DHCP-assigned information. When the lease reaches certain milestones, the client will attempt to renew its DHCP information.

Feedback will be sent to Microsoft: By pressing the submit button, your feedback will be used to improve Microsoft products and services. Privacy policy. Skip to main content. This browser is no longer supported. See the netmasks 4 man page for information on netmasks. After the DHCP servers determine the client's network, the servers select an appropriate IP address and verify that the address is not already in use.

The DHCP servers then respond to the client by broadcasting an offer message. The offer message includes the selected IP address and information about services that can be configured for the client. Each server temporarily reserves the offered IP address until the client determines whether to use the IP address. The client selects the best offer, based on the number and type of services offered.

The client broadcasts a request that specifies the IP address of the server that made the best offer. The broadcast ensures that all the responding DHCP servers know that the client has chosen a server.