27 timer t1 and t2 start when client is bound client

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Unformatted text preview: and sends a DHCPREQUEST to the server If server accept, a DHCPACK contains a new lease time (C) Herbert Haas 2005/03/11 28 After the client enters the BOUND state, both timers start. If the client still in the network after T1 expired, the client sends out an DHCPREQUEST message, because he wants to renew the lease. 28 Timer If the lease could not be RENEWED after T1, the client makes another try after T2 Client try to connect other DHCP server DHCP server can answer with DHCPACK and RENEWING the lease DHCPNACK to force the client to reinitialize (C) Herbert Haas 2005/03/11 29 T2 is only a 2nd try. If something go wrong at the first time, the client still have the chance to renew his lease after T2 expired. In this try he also connect other DHCP servers. If the client receipt a DHCPACK his lease is renew. If the client gets a DHCPNACK message the lease expired and the client starts from the beginning (he sends out a DHCPDISCOVER to all DHCP servers). 29 Subnets DHCP is related to BootP DHCP messages are broadcast based Not forwarded by routers Or routers are configured as BOOTP Relay Agent (C) Herbert Haas 2005/03/11 30 DHCP and BOOTP sends out his packets via IP broadcast. But routers not forwarded broadcasts -> broadcast storm in the whole network. But there is a special function on routers called “BOOTP Relay Agent” which allows the routers to forward this special BOOTP/DHCP messages. 30...
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This document was uploaded on 02/12/2014.

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