How do I find out my ISP's IP address?

By treetops ยท 11 replies
Jan 18, 2012
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  1. No I am not doing anything crafty I wouldn't know how to anyways. Yes it is for school, I am reviewing questions for my final but I can't figure this one out. Are they talking about their website cause thats easy. Or do I have to find out like what their mega computers ip address is spamming me my sweet bandwidth? If so how?

    p.s. hu ray i get to write in bad grammer for a change who learned you how to spoke?
  2. Leeky

    Leeky TS Evangelist Posts: 3,797   +117

    Your ISP will have multiple IP addresses.

    If what your asking is how do you find out YOUR IP address:

    If you want to know the IP address of a particular site, fire up cmd.exe in Windows (start run/search box, type cmd and hit enter.

    Then type: ping (or whatever website you need to know).

    Pinging [] with 32 bytes of data:
    Reply from bytes=32 time=18ms TTL=244
    Reply from bytes=32 time=15ms TTL=244
    Reply from bytes=32 time=14ms TTL=244
    Reply from bytes=32 time=35ms TTL=244
    Ping statistics for
        Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
    Approximate round trip times in milli-seconds:
        Minimum = 14ms, Maximum = 35ms, Average = 20ms
    That will reveal their IP address for you.
  3. treetops

    treetops TS Evangelist Topic Starter Posts: 2,044   +206

    I will clarify one review question is what is your ISP's ip address? How did you attain it?

    Yeah I know I can find websites and my ip very easy. They must mean my ISP website based on your response.
  4. Leeky

    Leeky TS Evangelist Posts: 3,797   +117

    I would ask for clarification on that question if I was you.

    The way it is worded could be considered confusing, and to my mind it could mean your ISP IP address, or the IP address of your ISP, both of which will be different.

    It could be the website of your ISP, e.g. in my case Virgin Media, but that is purely the public website IP address, and not the IP address of my ISP -- they will use hundreds of different IP's on nodes, exchanges, local service points, switches and dynamic IP's connecting to customers.

    For example, my IP address is dynamic. I share it with others in my area and we all run off the same local node. When my modem connects to the network, it leases it an IP address from a pool of available IP addresses. If I turn it off, then back on, it will usually re-lease me a new IP address different to my previous one. The IP has registered these blocks of IP addresses specifically for their companies usage, so it would not be uncommon for one large ISP to literally have hundreds of blocks of IP addresses.

    It is definitely a question you should clarify.
  5. jobeard

    jobeard TS Ambassador Posts: 10,835   +894

    The problem with the question is from what perspective do we evaluate what is meant by 'the ISP?'
    • my gateway to the ISP? (which is my view of the ISP)
    • the DNS addresses by the ISP?
    • or the ISP's connection to the Internet (ie their input)?

    Leeky makes a good point: "The IP has registered these blocks of IP addresses".

    Without much effort, you can use TRACERT GOOGLE.COM to find a path from you
    (when at home or at school) to the google website. This will have some information that will allow you find some answers
    First, verify you known a valid address for using nslookup
    Server:    << the DNS used to find
    Non-authoritative answer:
    Name:    [B][/B]
    Addresses:,,, [B][/B],
    now - - here's mine example of tracert:
    Tracing route to[B] [][/B]
    over a maximum of 30 hops:
      1    <1 ms    <1 ms    <1 ms  localrouter []
      2    20 ms    39 ms    13 ms [[COLOR="Blue"][/COLOR]]
      3     9 ms     9 ms     9 ms
      4    18 ms    21 ms    23 ms []
      5    22 ms    23 ms    23 ms
      6    11 ms    13 ms    12 ms []
      7    14 ms    12 ms    12 ms []
      8    14 ms    40 ms    13 ms
      9    13 ms    12 ms    13 ms
     10    14 ms    11 ms    12 ms
     11    12 ms    13 ms    14 ms [B][][/B]
    Trace complete.
    • Line 1 is always your router
    • Line 2 is your gateway address as announced by DHCP (also seen in ipconfig /all)
    • the last line should be as seen above by nslookup

    my gateway address is line 2 = =

    Using that IP address, we can discover the block of addresses as described by Leeky using a tool like Win32WhoiS which reports a ton of stuff including
    NetRange:       [COLOR="Blue"] -[/COLOR]
    CIDR:        [COLOR="Blue"][/COLOR]
    OriginAS:       AS11955, AS20001, AS21522
    NetName:        RRWE
    NetHandle:      NET-50-113-0-0-1
    [U]OrgName:        Road Runner HoldCo LLC[/U]
    OrgId:          RRWE
    Address:        13820 Sunrise Valley Drive
    City:           Herndon
    StateProv:      VA
    PostalCode:     20171
    Road Runner owns the block -

    Now here's a suprise when we ask what is line 3?
    [COLOR="Blue"]NetRange: -
    CIDR: [/COLOR]
    NetName:        RRACI
    NetHandle:      NET-76-166-0-0-1
    [U]OrgName:        Road Runner HoldCo LLC[/U]
    OrgId:          RRWE
    Address:        13820 Sunrise Valley Drive
    City:           Herndon
    StateProv:      VA
    PostalCode:     20171
    Road Runner also owns -
    In fact, continuing down the list, lines 2-5 are all Road Runner
    which demonstrates the admin's choice to control bandwidth and routing while
    within Road Runner and line 8 is Google.
    NetRange: -
    NetName:        GOOGLE
    NetHandle:      NET-72-14-192-0-1
    [U]OrgName:        Google Inc.[/U]
    OrgId:          GOGL
    Address:        1600 Amphitheatre Parkway
    City:           Mountain View
    StateProv:      CA
    PostalCode:     94043
  6. treetops

    treetops TS Evangelist Topic Starter Posts: 2,044   +206

    Thanks for the responses, I'm going to email my instructor and see whats what. I thought it would be something simple that I overlooked which it probably is but the wording like you all said is so wishy washy.
  7. treetops

    treetops TS Evangelist Topic Starter Posts: 2,044   +206

    Update they just meant my ISP website, I got 175\175 on my final woot, that was one of about 50 questions. Now I have to do my hard class Local Area Network Planning and Design.

    Software Installation - MS Windows was so much easier
  8. Shynash21

    Shynash21 TS Rookie

    go to
  9. jobeard

    jobeard TS Ambassador Posts: 10,835   +894

    oops; when accessing this from your own computer, it shows you YOUR ip address, not that of any other ISP (which is the question being discussed).
  10. PromiseKun

    PromiseKun TS Rookie

    I have an ethernet connection in home (I didn't paid anything,it's not used wire but whenever I plug it,pc shows no internet access),the office of ISP is in the ground floor.they have few server device
    using wireshark and netcut I found IP addresses and put 'em in IPv 4 ,but didnt work.those software didnt showed ip gateway.I tried to use ipconfing didn't work.
    how can I gain access to internet? I saw in wireshark that that isp use tp link router
    this isp is small one,so it'd use to get access over net,I think
  11. PromiseKun

    PromiseKun TS Rookie

    Tried gateway addresses according to ip I found didn't worked
    but the network number changes,pc shows Network 8/10 or unindentified and no internet access,
    but sometimes it shows "internet access" but sites doesnt load
  12. cliffordcooley

    cliffordcooley TS Guardian Fighter Posts: 9,396   +3,410

    You should start your own thread for help, instead of hijacking this 5 year old thread.
    learninmypc likes this.

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