Static IP vs. Reserve a DHCP address

Discussion in 'Mac Accessories' started by Le Big Mac, Apr 14, 2008.

  1. Le Big Mac macrumors 68020

    Le Big Mac

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    #1
    On Airport/TC, what is the difference between these two? In either case, the device will always get the same IP address, right? So is "reserve a DHCP" mean that all the network settings (subnet, dns server, etc.) will get automatically entered?
     
  2. kalex macrumors 65816

    Joined:
    Oct 1, 2007
    #2
    Static ip means it doesn't change and entered manually.

    Reserved DHCP means that same ip address is assigned to same device all the time, this is usually done by MAC address of each device.

    With reserved DHCP address all info is served by DHCP server. if you have static ip you have to enter it manually
     
  3. Sesshi macrumors G3

    Sesshi

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    #3
    Reserved DHCP is useful when you want your router to have full control over how IP addresses are assigned, and for other IP details to be sent to your devices while having manual control of the specific IP address. It's more organised and can make troubleshooting, etc easier. However, although it's very rare some devices don't play nice with reserved DHCP addresses.
     
  4. Le Big Mac thread starter macrumors 68020

    Le Big Mac

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    #4
    Thanks, so it's basically what I expected. Seems like reserved DHCP is the best of both worlds, unless the device doesn't play nice for some reason.

    Follow-up--in TC menu you can assign DHCP by Mac Address or device name. How can I find out the device name? The TC doesn't seem to show attached devices or allow one to assign a name, even to something like a Macbook.
     
  5. Sesshi macrumors G3

    Sesshi

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    #5
    Best to go by MAC address IMO. In a small home network it's unlikely to be a problem (MAC addresses are generally supposed to be unique, but because of the length of the address and how many devices there are out there with a MAC address, it is not unique in practice. But it's very unlikely you'll experience a dupe for home use).
     
  6. jeremy.king macrumors 603

    jeremy.king

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    #6
    I've never heard of this. Care to support that statement?

    At 48 bits, there are 281 TRILLION+ possible values - is this just the case of a lazy manufacturer or are you claiming that the world's has 281 trillion devices out there with MAC addresses?
     
  7. skorpien macrumors 68020

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    Jan 14, 2008
    #7
    I don't know about PC products, but my MBP has a place in the AirPort advanced prefs (I think) that allows you to specify a device name. I prefer the MAC address as well, as that will usually never change unless the hardware is swapped out.

    Another advantage that I've found to using reserved DHCP is if you travel with your computer, you don't have to change your IP settings to log on to another network. Before I used reserved DHCP, I was in a coffee shop and although I found the network and it was unsecured, I couldn't log in because my MBP was still trying to use the static IP from my home network.
     
  8. Le Big Mac thread starter macrumors 68020

    Le Big Mac

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    #8
    Okay. Only issue I found so far with that is there are separate MAC addresses for the wireless and wired connections, so it looks like I'd need to add both, right?

    (Since this isn't an office, if I have the really bad luck to get a duplicate MAC in the 5-10 devices we'll have connected I'll deal with the problem then. But with 281T+, I like my chances).
     
  9. skorpien macrumors 68020

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    Jan 14, 2008
    #9
    My old router gave the option to clone your PC's MAC address... And although it is highly unlikely, unless there was a database with all used MAC addresses to ensure you do not accidentally duplicate one (which there could very well be, in which case my argument doesn't stand), there's no guarantee that the one that's assigned to a device is unique.
     
  10. Le Big Mac thread starter macrumors 68020

    Le Big Mac

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    #10

    Yeah, that's a really good point and reminds me why I liked this option--you can leave the settings at DHCP and not muss with them. particularly good for my wife, who uses a notebook--I don't dare try to teach her how to change the IP settings . . . .:rolleyes:
     
  11. skorpien macrumors 68020

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    #11
    If you're going to be connecting by both, yes. I think you can reserve the same IP for two different MAC addresses, and since when you're wired you can't be wireless and vice versa, it shouldn't pose a problem.
     
  12. jeremy.king macrumors 603

    jeremy.king

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    #12
    It's not overridden at a hardware level.
     
  13. sblasl macrumors 6502a

    sblasl

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    Heber Springs, AR
    #13
    kingjr3, A little off topic. Is that a Rhodesian Ridgeback in your profile photo?

     
  14. jeremy.king macrumors 603

    jeremy.king

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    #14

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