Folks: I am wondering why I always get the same IP address even after I do ipconfig /release and ipconfig /renew several times. Is my IP info stored somewhere as cache? If so, is there any way to clean it up? I need to have a different IP for some testing purpose. Could anybody help me please? gangchen

perhaps you can answer the question of how you are getting your ip address? Are you autoassigned or do you have a static entry [tcp/ip protocol properties in network properties]

Yes your IP address assignment is stored somewhere else off your PC. If you access the internet directly through a modem or broadband modem, your IP is "leased" from your ISP, usually for 48 hours up to about 6 months, some more, some less. So when you perform ipconfig/release and /renew, you are probably going to get the same IP address, unless you stay off your ISP for a week or more. If you use a home router, your IP is assigned by the router and you can control how long that IP address is assigned to you, and what IP to assign your PC. HTH

Two possible reasons, asuming you are configured as a DHCP client to start: * Lease duration-You maintain the same numneric ip assignment for the length of the lease, even if you release & renew which leasds to reason two * MAC address. The ip address assignment is linked to your MAC address. For example, if you are set for DHCP and move your PC to a different subnet (assuming for the moment you are on a subnetted network) you will then receive a different ip address representing the scope/pool/range of addresses on that subnet. If you get your assignment from an ISP the answer may be slightly different depending on how they issue addresses and what ranges they manage.

If you have a "static" IP address set up in your TCP/IP configuration your PC will always try to connect using that IP address. If instead you select "Assign IP addresses automatically" every time you connect to the DHCP server your machine will request the first available IP address. Releasing this IP address may not get you a new one: Once an address is released it's returned to the table of available IP addresses and usually winds up at the top of the list. If no one else requests an IP between your /release and /renew you'll get the same IP address back. You have no way on your end of rejecting an IP assignment: You can set up a script to /release and /renew until you get another assignment but that depends on someone else connecting during the interim. With some servers you may have to wait a LOOOOONNNNNNGGGGGG TIIIIMMMMEEEEE. If you're just trying to mask your IP address to avoid admin blocks or fool people into thinking you're someone else in an online discussion (a) shame on you and (b) use a proxy server.

The DHCP client process is basicaly in 4 steps. When it start, it first verify if there is already a known dhcp server in memory. Then it verify if an IP address in already assigned. Before sending a "dhcp discover" it will try to reach the last dhcp server and will try to renew a known IP before asking for a new one. In order to force a complete dhcp cycle, disconnect the network before you do a release/renew. plug it back and redo a release/renew. Danny Larouche, cwna ciw