cable modem/router question

Discussion in 'Mac Basics and Help' started by atari1356, Feb 19, 2007.

  1. atari1356 macrumors 68000


    Feb 27, 2004
    The company I work for just got cable modem service today... but it seems to only work for one person on the network.

    We have the cable modem connected to an old Linksys EEHUB16 hub, which runs cables out to all of the computers. I had thought that each computer would be able to obtain an IP address using DHCP through the cable company (Brighthouse).... but maybe they only allow one ip address?

    Do we need a new router that assigns DHCP addresses itself?

    I haven't contacted the cable company about the issue yet, because I don't want them to try and sell me some extra service that we don't really need... although I'll probably end up calling them in a little while anyways.

    Thanks for any advice.
  2. Mac the knife macrumors member

    Jul 6, 2006
    Sounds to me that you do need a new router. I don't know about the cable in your area but many (like where I am) only allow one address. The router should be the only thing the cable is "seeing". Then the router assigns addresses to all the computers for it's own communications.
  3. aristobrat macrumors G4

    Oct 14, 2005
    Right, right.

    The one public IP address assigned by the cable company should go the router (for the WAN side).

    The router then handles sharing that one address with everyone on the LAN side (using a range of private IP addresses). It'd be a lot easier for you if you let the router use DHCP to give out and manage those private addresses. I haven't seen a router that can't handle that.
  4. eluk macrumors 6502a


    Dec 14, 2006
    East London, UK
    The Linksys EEHUB16 is a hub rather than a router and so doesn't have DHCP. Therefore can assign IPs to the workstations.
  5. Sun Baked macrumors G5

    Sun Baked

    May 19, 2002
    Yep, time to get a NAT router to replace the hub.

    If he asks the cable company to assign addresses -- it might cost more money. The NAT router would likely be the cheapest solution.
  6. atari1356 thread starter macrumors 68000


    Feb 27, 2004
    Right... I didn't understand the naming difference when I wrote the first post, but understand now. Thanks for the clarification.
  7. atari1356 thread starter macrumors 68000


    Feb 27, 2004
    Here's an idea... do you think this will work?

    In the office we also have a D-Link 624 wireless router (that also has four ethernet ports). I've used it in the past to connect a computer via ethernet to one of the four ports - and it assigns the computer an IP address via DHCP. (obviously I can also use it wirelessly, but not all of our computers have wireless cards in them)

    What if I hooked the cable modem to the D-Link wireless router, then ran an ethernet cable from one of it's four ports to the Linksys hub (which then runs cables to all of the computers)?

    Would the D-link router be able to assign all those IP addresses (around 8 computers) via DHCP from that one ethernet cable?
  8. SMM macrumors 65816


    Sep 22, 2006
    Tiger Mountain - WA State
    You might also consider a getting a combination Firewall, Router, DHCP Server. Gives you a little more peace of mind at a very reasonable entry point. I personally like the Netgear, others like Linksys better. Both are good choices. For a little more, you can connect the router into a 12/24 port Gigabyte switch, with a wireless access point.
  9. aristobrat macrumors G4

    Oct 14, 2005
    That should work fine.

    The only problem you might run into is if the old Linksys hub can't figure out that you're using one of the ports for an upstream link. Sometime's there's a switch on the box that needs to get set (or a special port that must be used).
  10. atari1356 thread starter macrumors 68000


    Feb 27, 2004
    I set it up this way today and so far everything is working great:

    [cable modem] <----> [d-link 624 wireless router] <----> [linksys hub]

    At the moment we have 6 computers on the network, and it's much quicker than the old antiquated ISDN line.

    Thanks for the advice everybody. :)

Share This Page