Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie

Two IP addresses to keep to myself

Options
  • 16-01-2008 3:17pm
    #1
    thehegdes
    Registered Users Posts: 76 ✭✭


    Hi Networking Gurus,

    I may sound a little crazy, but believe me this is my requirement.

    I need two IP address to two interfaces on two different devices to commmunicate, which are not commonly used either in private or public address space. Can you suggest any such two addresses?

    Can I use the reserved Class E addresses for this?

    Cheers,
    TheHegdes


Comments

  • Options
    #2
    monkey tennis
    Closed Accounts Posts: 583 ✭✭✭monkey tennis


    thehegdes wrote: »
    Can I use the reserved Class E addresses for this?

    Depends on the TCP/IP stack, but I wouldn't be surprised if it didn't work.

    Surely there can't be a reason why you can't use a /30 subnet in a private address range?


  • Options
    #3
    Spear
    Moderators, Computer Games Moderators, Technology & Internet Moderators, Help & Feedback Category Moderators Posts: 25,349 CMod ✭✭✭✭Spear


    thehegdes wrote: »
    Hi Networking Gurus,

    I may sound a little crazy, but believe me this is my requirement.

    I need two IP address to two interfaces on two different devices to commmunicate, which are not commonly used either in private or public address space. Can you suggest any such two addresses?

    Can I use the reserved Class E addresses for this?

    Cheers,
    TheHegdes

    172.16.*.* to 172.32.*.* are private addresses that are rarely used.


  • Options
    #4
    thehegdes
    Registered Users Posts: 76 ✭✭thehegdes


    Yeah, but they can still be used right?

    I need two IP addreses (if possible) to communicate between 2 devices all the time irrespective of what the user configures for his LAN machines.


  • Options
    #5
    Spear
    Moderators, Computer Games Moderators, Technology & Internet Moderators, Help & Feedback Category Moderators Posts: 25,349 CMod ✭✭✭✭Spear


    thehegdes wrote: »
    Yeah, but they can still be used right?

    I need two IP addreses (if possible) to communicate between 2 devices all the time irrespective of what the user configures for his LAN machines.

    Yes, they're still available for use. Why not use SMB/Netbios names instead then, and let them be resolved to IPs?


  • Options
    #6
    thehegdes
    Registered Users Posts: 76 ✭✭thehegdes


    Sorry Spear, I do not understand what you are saying. Can you explain please..


  • Advertisement
  • Options
    #7
    Spear
    Moderators, Computer Games Moderators, Technology & Internet Moderators, Help & Feedback Category Moderators Posts: 25,349 CMod ✭✭✭✭Spear


    thehegdes wrote: »
    Sorry Spear, I do not understand what you are saying. Can you explain please..

    Use machine names and allow the local machines to resolve them to IP's, rather than rely on hardcoded IP's.


  • Options
    #8
    thehegdes
    Registered Users Posts: 76 ✭✭thehegdes


    Hmm.. is this still possible if the LAN interface (for which the addresses are served by a DHCP server) and the other interface (which I'm saying needs a unique ip - the IP may be static or may be served by another DHCP server)


  • Options
    #9
    Spear
    Moderators, Computer Games Moderators, Technology & Internet Moderators, Help & Feedback Category Moderators Posts: 25,349 CMod ✭✭✭✭Spear


    thehegdes wrote: »
    Hmm.. is this still possible if the LAN interface (for which the addresses are served by a DHCP server) and the other interface (which I'm saying needs a unique ip - the IP may be static or may be served by another DHCP server)

    I need to clarify what you're attempting to do. Is the traffic meant to be over a LAN only, or does it need to transit the net as well?


  • Options
    #10
    thehegdes
    Registered Users Posts: 76 ✭✭thehegdes


    ok.. what I exactly need is this..

    Internet/WAN <
    > [(public IP) DSL Modem (unique IP)] <
    > [(unique IP) Hub (private IP)] <
    > [(private IP's) LAN]

    I want 2 unique IP addresses which I can use all the time to communicate between DSL Modem and Hub without restricting the HUB user to use desired IP address ranges on the LAN

    Hope this explains my requirement.. let me know if you need more info

    Thanks!


  • Options
    #11
    Spear
    Moderators, Computer Games Moderators, Technology & Internet Moderators, Help & Feedback Category Moderators Posts: 25,349 CMod ✭✭✭✭Spear


    thehegdes wrote: »

    I want 2 unique IP addresses which I can use all the time to communicate between DSL Modem and Hub without restricting the HUB user to use desired IP address ranges on the LAN

    Hope this explains my requirement.. let me know if you need more info

    Thanks!

    If the hub runs DHCP this should be easy enough to arrange.


  • Advertisement
  • Options
    #12
    thehegdes
    Registered Users Posts: 76 ✭✭thehegdes


    HUB runs DHCP only on the LAN side. On the other side, its a DHCP client and the address is served by the DSL modem.


  • Options
    #13
    Spear
    Moderators, Computer Games Moderators, Technology & Internet Moderators, Help & Feedback Category Moderators Posts: 25,349 CMod ✭✭✭✭Spear


    thehegdes wrote: »
    HUB runs DHCP only on the LAN side. On the other side, its a DHCP client and the address is served by the DSL modem.

    Then statically assign two IP's of choice from a private address range to the DSL modem and hub side that faces it. Set DHCP on the hub so that it excludes the addresses used previously. Hence no machines on the LAN side will get those addresses and no clashes should occur.


  • Options
    #14
    thehegdes
    Registered Users Posts: 76 ✭✭thehegdes


    Yeah.. this is the last resort. But, we did not want to do this. So you say there is no other way of doing this?


  • Options
    #15
    Spear
    Moderators, Computer Games Moderators, Technology & Internet Moderators, Help & Feedback Category Moderators Posts: 25,349 CMod ✭✭✭✭Spear


    thehegdes wrote: »
    Yeah.. this is the last resort. But, we did not want to do this. So you say there is no other way of doing this?

    The LAN addresses and the static ones can be from two different ranges if that helps. If nothing else the modem and hub should have their own netbios names. Regardless of what IP's they have they should be resolvable.


  • Options
    #16
    thehegdes
    Registered Users Posts: 76 ✭✭thehegdes


    Say choosing from two different ranges option is ruled out. So, what is the other option you are suggesting... netbios?? I do not know anything about this... I will look up the web on this. In the mean while, can you give me some hint please?

    Thanks!


  • Options
    #17
    Spear
    Moderators, Computer Games Moderators, Technology & Internet Moderators, Help & Feedback Category Moderators Posts: 25,349 CMod ✭✭✭✭Spear


    thehegdes wrote: »
    Say choosing from two different ranges option is ruled out. So, what is the other option you are suggesting... netbios?? I do not know anything about this... I will look up the web on this. In the mean while, can you give me some hint please?

    Thanks!

    A machines hostname can be resolved to an IP as well, this will allow the names to resolved to dynamically allocated IP's, since the names will be set statically.


  • Options
    #18
    thehegdes
    Registered Users Posts: 76 ✭✭thehegdes


    ok... but this has to be supported on what both the DSL modem and the Hub? So, there will be a netbios server running on DSL Modem and a client on the Hub?

    How is this different from DNS?

    Thanks!


  • Options
    #19
    Spear
    Moderators, Computer Games Moderators, Technology & Internet Moderators, Help & Feedback Category Moderators Posts: 25,349 CMod ✭✭✭✭Spear


    thehegdes wrote: »
    ok... but this has to be supported on what both the DSL modem and the Hub? So, there will be a netbios server running on DSL Modem and a client on the Hub?

    How is this different from DNS?

    Thanks!

    Not a Netbios/SMB server, there's no need for one. Probably best to forget the mention of netbios it'll only confuse things as netbios name and hostname aren't quite the same.

    http://en.wikipedia.org/wiki/NetBIOS

    The DSL modem and hub will probably have TCP/IP hostnames which can be used. If you're running a DNS server it's probably registered these names.


  • Options
    #20
    thehegdes
    Registered Users Posts: 76 ✭✭thehegdes


    ok.. thanks Spears.. I'll check this out!

    In the mean while, if you have some brainwave, please let me know.

    Cheers!


  • Options
    #21
    Spear
    Moderators, Computer Games Moderators, Technology & Internet Moderators, Help & Feedback Category Moderators Posts: 25,349 CMod ✭✭✭✭Spear


    thehegdes wrote: »
    ok.. thanks Spears.. I'll check this out!

    In the mean while, if you have some brainwave, please let me know.

    Cheers!

    I still don't see what's wrong with the earlier suggestion about changing the DHCP range. It seems the easiest option and keeps everything easily managed.


  • Advertisement
  • Options
    #22
    thehegdes
    Registered Users Posts: 76 ✭✭thehegdes


    I agree. We might eventually end up doing this :)

    Thanks for all your inputs; really appreciate your help

    Cheers!


  • Options
    #23
    Webmonkey
    Registered Users Posts: 9,579 ✭✭✭Webmonkey


    Just wondering why Spear's suggestion regarding the DHCP is a last offer? - I can't think of anything more straight forward than it and you only loose two IP's ?


Advertisement