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IP configuration? how 2 do manually

  1. Oct 3, 2004 #1
    does anyone noe how to configure ur ip address manually via the local area connection (lan) properties?

    i can change it but so can anyone but how do u make one that works? thats my problem, can anyone help? i have a static connection with a cable company, and my ip is assigned by the dhcp (what is that) so can i manually configure it effectively? do u just mess around with the numbers until u get one or is there trick or specif rule or anything to it??

    wut can u put under the actual ip address box, the subnet mask, the default gateway, preferred dns server, alternate dns server??

    thx4 the help!!

    also if u wait until ur "lease" expires and u turn off ur modem at that point in time, dissallowing ur modem to renew ur current lease with that specific ip address, can u get a new one? any help appreciated
  2. jcsd
  3. Oct 4, 2004 #2
    static connection through a dhcp??
    u sure ??
    dhcp is dynamic host configuration protocol
    usually used for dynamic IP

    do u have a static IP or dynamic IP?

    if its a static IP then ....
    what do u need to actually configure the network??
    Ans :
    1> your IP address (ask ur ISP if u don't have it)
    should be something like or or something like that
    2> a subnet mask (ask ur ISP if u don't have it)
    should be something like or or something like that
    3> a gateway address (ask ur ISP if u don't have it)
    should be something like or or something like that
    4> a dns address (ask ur ISP if u don't have it)
    should be something like or something like that

    **alternate dns is not required but if ur ISP provides it then well and good**

    If its a dynamic IP then ....
    u don't have to almost do anything just click on
    Obtain IP address automatically and forget it

    if ur current IP address is not assigned to someone else by ur ISP then u prolly will have ur old IP address unless u demand it to be changed ... some ISP give that facility
    (Note whatever i said was with respect static IP)

    -- AI
  4. Oct 4, 2004 #3


    User Avatar

    Staff: Mentor

    Could you tell us what you are trying to accomplish? If its working, its best to leave it alone. Dynamic IP with a long lease is still dynamic and eventually will change.
  5. Oct 4, 2004 #4
    first off thanks for the replies.

    to tenaliraman: i was under the impression that a static ip is one that doesn't change, and mine's hasn't changed for a while. so i thought i might have a static ip. but u have recognized something, dynamic ip's are temporary, right? so does that mean that i have a dynamic ip that renews under the lease thus leaving me with the same ip as before? is that what's happening? :bugeye: :uhh:

    so if lets say i turn the cable modem off and unplug the cable cord from the modem let's say five minutes before my ip lease expires, and i plug it all back in and hook everything up let's say the next morning at around 7-8 am in the morning, would it change? do you think it would? :confused:

    ur right, it is working and all but i just wanted to understand/test how and when it would change. :smile: are you able to help me? :smile:
  6. Oct 5, 2004 #5
    if u are getting the same IP and u r working through DHCP then this prolly has 2 possible reasons
    1> its pure coincidence that u are getting same IPs or
    2> its how ur ISP has configured his server at his place

    U see in a DHCP, there is a first stage of remote login where a computer connects itself to a remote ISP computer. At this stage the user computer is provided with an IP by the ISP ....

    so it is entirely in the hands of the ISP server with regards to what IP u get ... it is possible for him to allocate the same IP to u whenever u login ... so that may be the case ....

    ofcourse as i said above , it may be pure coincidence (chance tho of this happening are less).

    -- AI
  7. Oct 5, 2004 #6


    User Avatar

    Staff: Mentor

    Probably not. For this reason:
    It really is tough to know what they are up to.
  8. Oct 5, 2004 #7
    ooohhhhhhhhh i c

    thank u both for the help :smile: :smile: :smile: :smile:

    however i will try my idea on the 8th and let u noe how it turned out and what happened. :wink: :wink: :smile: hopefully my hypothesis is correct. :cool: :wink: :smile:
  9. Oct 6, 2004 #8
    It most likely will not change on the 8th. Most cable providing ISPs will have your IP address tied to the MAC address of your cable modem. (every time your ISP sees a your MAC address it will allocate a reserved IP schema for it)

    If on an analog modem or DSL connection you would see the change of your IP quite often.

    Not to be anal here or anything but...

    10.x.y.z, and 192.x.y.z are private networks. No ISP will assign this kind of address from their DHCP servers because it is a bogus, non-valid address. Routers with NAT capability will assign this type of address and the translate it to the public address on the WAN side of the router.

    IP = 4 octets... left set of octets designates the network address and right side octets designates host address. Any host on the same network can communicate to another host on that network without a gateway/router. If 2 hosts are on separate networks they will need a router/gateway to communicate to each other.

    Subnet Mask = this was invented to create more network addresses by sacrificing host addresses. We can go into detail about this if you are interested.

    Default Gateway = This will be the address the closest router on your network. The router will have the ability to communicate with external networks.

    DNS = This is like a phone book. But instead of translating people's names into telephone numbers, it translates Website names into IP address...so when you type into your browser www.physicsforums.com your computer will ask your assigned DNS server what the IP of that site is and the DNS server will respond saying "" and then your browser will contact www.physicsforums.com

  10. Oct 6, 2004 #9
    One small addition I wanted to make that I don't think was brought up. First, I agree that most cable providers nowadays will tie your IP schema to a MAC address. This is to prevent someone from hooking all 10 of thier LAN PC's to 10 IP's in the DHCP pool without paying for them.

    Dynamic IP's in theory CAN change. your computer automatically grabs an IP address from a predetermined range of IP addresses called a DHCP pool, on the DHCP server. This might be something like to or something along those lines. A DHCP address lasts for 7 days typically, then requeries the DHCP server to see if that IP address is still valid. If it is, it will keep the same IP address. If not, it grabs another one. If you manually release and renew right away, it will typically grab the same one because it's still available. However, let's say you released then didn't renew your IP for like a month. During that timeframe your IP is in the "available" list, and might be grabbed by another PC. If that happens, then you'll get another IP. But any short releasing of the IP grabs the same one. That is why you always retain the same IP address when you're DHCP.
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