How often IP phone request information from DHCP server?

[webstd.design]

How often IP phone requests information from DHCP server?

[timurbayazitov]

Obviously, it depends on DHCP server settings, including lease time, renewal time, rebinding time. IP phone just operates according these settings and DHCP protocol. See http://www.tcpipguide.com/free/t_DHCPLeaseRenewalandRebindingProcesses-2.htm for detailed description.

[webstd.design]

My windows admin said that IP phone should have some parameters that doesn't depend on DHCP server. Is it right?

[timurbayazitov]

No, you can only manually release IP address acquired from server or completely disable DHCP using phone configuration menu.

[Nicholas Matthews]

The phone will ask for a DHCP renew once half the lease time has gone by. Depending upon your lease time you'll have different results.

An IP address and TFTP address are all the phone really needs to register, and both of these are delivered by the DHCP server. You can statically set this on the phone, but it's not scalable.

hth,

nick