Re: IP address allocation

From: Adam Newhard (atnewhard_at_microstrain.com)
Date: 07/31/03

  • Next message: Adam Overlin: "RE: Cisco Workaround" 
    To: <security-basics@securityfocus.com>
Date: Thu, 31 Jul 2003 12:41:51 -0400

    Do those unused ip addresses point anywhere??? i.e. if you type them into a
    browser, to they load up a web page or do they just not go anywhere??? I
    would imagine if they sold you a block of ip addresses, they have a script
    that'll generate all the dns entries for them and someone just screwed up or
    they don't know that you're not using those ip addresses. If they don't
    point anywhere or do anything, it shouldn't really cause too much harm b/c
    they're not associated with anything. I do know a bunch of places that do
    still have dns entries for unused ip addresses they own, but simply to make
    their life easier and for descriptive purposes (like to associate the ip
    with a company or a location b/c they're too lazy to go look it up in their
    paper records). Shouldn't be a problem, but if you're concerned about it,
    why don't you call them and ask them why??? (not being rude, that was a
    serious question).
    adam
    ----------------------------------------------------
    Adam Newhard
    Microstrain, Inc.
    If vegetarians eat vegetables, watch out for humanitarians

    ----- Original Message -----
    From: "Terry" <tech@futurecourse.com>
    To: <security-basics@securityfocus.com>
    Sent: Thursday, July 31, 2003 5:41 AM
    Subject: IP address allocation

    > Hi,
    >
    > I've googled but haven't really come across anything that answers my
    > questions. Is it common practice for ISPs to allocate a block of
    > addresses to a customer and put in DNS records for ones that are
    > unused?
    >
    > For example, xxx.8-xxx.15 is assigned to the customer. Customer uses
    > xxx.9 for the router and xxx.10 for web server. xxx.11-14 are unused.
    > I would expect to see DNS records for xxx.9 and xxx.10 but not for the
    > rest of the block. Am I wrong? If there are DNS records for the rest
    > of the IPs, why is that? Is there some security reason for doing
    > this?
    >
    > --
    > Regards,
    > Terry
    >
    >
    > --------------------------------------------------------------------------
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    > -------------------------------------------------------------------------- 

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>
>
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  • Next message: Adam Overlin: "RE: Cisco Workaround"

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