Re: STEP 2, fixing dhclient behaviour with multiple interfaces

From: Terry Lambert (tlambert2_at_mindspring.com)
Date: 07/31/03

  • Next message: Terry Lambert: "Re: gcc segfault on -CURRENT (cvs yesterday)"
    Date: Thu, 31 Jul 2003 01:17:16 -0700
    To: Tony Finch <dot@dotat.at>
    
    

    Tony Finch wrote:
    > Terry Lambert <tlambert2@mindspring.com> wrote:
    > >I can't wait for IPv6 stateless autoconfiguration plus SLPv2 so
    > >we can get rid of all this DHCP crap once and for all. 8-(.
    > >SLPv2 is used to find the gateway and DNS server, and after that,
    > >everything "magically works".
    >
    > I thought that the gateway address is (already) set up using
    > RFC 2461 router and prefix discovery.

    Won't work for any U.S. Cable modems or DSL, which is based on
    ATM (which is an NBMA-type link). It also doesn't work for
    ISDN ("iDSL"), which is an SDMS-type link and doesn't have full
    prefix information available.

    So basically, if you have broadband, it won't work.

    I think that any broadcast system, like 802.11a, 802.11b,
    802.11g, Motorolla Canopy, etc.. will also have issues, since
    the machines are implicitly multihomed for the nearest one.

    Finally, I haven't seen a router with ND turned on, if it was
    even supported, so it wouldn't advertise or respond to any
    solicitations to advertise (basically, you'd end up with an
    ability to use this to fire off indirect DOS attacks against
    third parties, so it tends to be disabled, or at least that
    was the explanation I was given). Basically, this leaves the
    client machine playing by the ND rules in the "INCOMPLETE"
    state, with no one to talk to.

    Microsoft actually solved this problem for IPv4 in link.local
    with their "Internet Connection Sharing" product at one time,
    but then went back to DHCP in later releases for reasons unknown
    (maybe because of 802.11 base-station-mode cards becoming
    available for Windows... who knows?).

    In any case, ND is kind of like DHCP, in that explicit support
    for the protocol is needed in order for both the client and
    server to communicate, which is kind of what I thought people
    needed to get away from when I was talking about losing DHCP.

    -- Terry
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  • Next message: Terry Lambert: "Re: gcc segfault on -CURRENT (cvs yesterday)"

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