windows – 为什么DHCP服务器需要静态IP地址？

My understanding of DHCP is,a client broadcasts a DHCP Discovery
request on the network,and any device on the network can respond.

客户端也可以发出单播DHCP请求,更新请求以单播方式进行,因此客户端直接请求DHCP服务器.
如果DHCP更改了原始IP地址怎么办？续订将失败,下一个请求将以广播形式进行.这不是一种可以优化网络流量的行为.

微软：

Renewing a Lease The DHCP client first attempts to renew its lease
when 50 percent of the original lease time,known as T1,has passed.
At this point the DHCP client sends a unicast DHCPRequest message to
the DHCP server that originally granted its lease. If the server is
available,and the lease is still available,the server responds with
a unicast DHCPAck message and the lease is renewed.

Source

ISC：

Internet Systems Consortium DHCP Client 4.2.2
Copyright 2004-2011 Internet Systems Consortium.
All rights reserved.
For info,please visit https://www.isc.org/software/dhcp/

Listening on LPF/eth0/00:0c:29:ac:18:75
Sending on   LPF/eth0/00:0c:29:ac:18:75
Sending on   Socket/fallback
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 7 << First request
DHCPREQUEST on eth0 to 255.255.255.255 port 67
DHCPOFFER from 10.0.0.253
DHCPACK from 10.0.0.253
bound to 10.0.0.6 -- renewal in 133 seconds.



DHCPREQUEST on eth0 to 10.0.0.253 port 67 << Renewal
DHCPACK from 10.0.0.253
bound to 10.0.0.6 -- renewal in 119 seconds.
DHCPREQUEST on eth0 to 10.0.0.253 port 67
DHCPACK from 10.0.0.253
bound to 10.0.0.6 -- renewal in 118 seconds.

Once the lease has been granted,however,future DHCP
DHCPREQUEST/RENEWAL messages are unicast directly to the DHCP
Server

Source