Why does my public IP change when I plug in different devices into the modem?
If I plug my router into my modem, I have one public IP address (as reported by https://www.whatismyip.com and the like). When I plug my computer directly into the modem, my public IP address changes. If I go back to using the router, my public IP address returns to its original value.
Why are my public IP addresses specific to the devices that plug into the modem, rather than staying with cable modem itself?
networking router ip modem isp
asked Feb 20 at 19:40
MaxBMaxB
1569
|
show 3 more comments
If I plug my router into my modem, I have one public IP address (as reported by https://www.whatismyip.com and the like). When I plug my computer directly into the modem, my public IP address changes. If I go back to using the router, my public IP address returns to its original value.
Why are my public IP addresses specific to the devices that plug into the modem, rather than staying with cable modem itself?
networking router ip modem isp
asked Feb 20 at 19:40
MaxBMaxB
1569
1
When a computer is connected directly to the modem, do you see the same public address in the computer's own network connection info? For example inipconfigorncpa.cplor the Windows' settings app?
– grawity
Feb 20 at 19:49
Are you sure you are not seeing a10.x.x.xor192.x.x.xaddress when you use your router?
– JakeGould
Feb 20 at 19:54
@JakeGould: It would be difficult for whatismyip.com etc to report such addresses...
– grawity
Feb 20 at 19:56
@grawity I guess it could be something like what this thread addresses.
– JakeGould
Feb 20 at 20:07
@JakeGould Thanks. Still unclear why the ISP is doing this instead assigning the IP address to the MODEM. But I'll delete since it's a dupe.
– MaxB
Feb 20 at 20:11
|
show 3 more comments
If I plug my router into my modem, I have one public IP address (as reported by https://www.whatismyip.com and the like). When I plug my computer directly into the modem, my public IP address changes. If I go back to using the router, my public IP address returns to its original value.
Why are my public IP addresses specific to the devices that plug into the modem, rather than staying with cable modem itself?
networking router ip modem isp
asked Feb 20 at 19:40
MaxBMaxB
1569
If I plug my router into my modem, I have one public IP address (as reported by https://www.whatismyip.com and the like). When I plug my computer directly into the modem, my public IP address changes. If I go back to using the router, my public IP address returns to its original value.
Why are my public IP addresses specific to the devices that plug into the modem, rather than staying with cable modem itself?
networking router ip modem isp
networking router ip modem isp
asked Feb 20 at 19:40
MaxBMaxB
1569
asked Feb 20 at 19:40
MaxBMaxB
1569
edited Feb 21 at 16:04
MaxB
asked Feb 20 at 19:40
MaxBMaxB
1569
asked Feb 20 at 19:40
MaxBMaxB
1569
asked Feb 20 at 19:40
MaxBMaxB
1569
1569
1
When a computer is connected directly to the modem, do you see the same public address in the computer's own network connection info? For example inipconfigorncpa.cplor the Windows' settings app?
– grawity
Feb 20 at 19:49
Are you sure you are not seeing a10.x.x.xor192.x.x.xaddress when you use your router?
– JakeGould
Feb 20 at 19:54
@JakeGould: It would be difficult for whatismyip.com etc to report such addresses...
– grawity
Feb 20 at 19:56
@grawity I guess it could be something like what this thread addresses.
– JakeGould
Feb 20 at 20:07
@JakeGould Thanks. Still unclear why the ISP is doing this instead assigning the IP address to the MODEM. But I'll delete since it's a dupe.
– MaxB
Feb 20 at 20:11
|
show 3 more comments
1
When a computer is connected directly to the modem, do you see the same public address in the computer's own network connection info? For example inipconfigorncpa.cplor the Windows' settings app?
– grawity
Feb 20 at 19:49
Are you sure you are not seeing a10.x.x.xor192.x.x.xaddress when you use your router?
– JakeGould
Feb 20 at 19:54
@JakeGould: It would be difficult for whatismyip.com etc to report such addresses...
– grawity
Feb 20 at 19:56
@grawity I guess it could be something like what this thread addresses.
– JakeGould
Feb 20 at 20:07
@JakeGould Thanks. Still unclear why the ISP is doing this instead assigning the IP address to the MODEM. But I'll delete since it's a dupe.
– MaxB
Feb 20 at 20:11
1
1
When a computer is connected directly to the modem, do you see the same public address in the computer's own network connection info? For example in
ipconfig or ncpa.cpl or the Windows' settings app?– grawity
Feb 20 at 19:49
When a computer is connected directly to the modem, do you see the same public address in the computer's own network connection info? For example in
ipconfig or ncpa.cpl or the Windows' settings app?– grawity
Feb 20 at 19:49
Are you sure you are not seeing a
10.x.x.x or 192.x.x.x address when you use your router?– JakeGould
Feb 20 at 19:54
Are you sure you are not seeing a
10.x.x.x or 192.x.x.x address when you use your router?– JakeGould
Feb 20 at 19:54
@JakeGould: It would be difficult for whatismyip.com etc to report such addresses...
– grawity
Feb 20 at 19:56
@JakeGould: It would be difficult for whatismyip.com etc to report such addresses...
– grawity
Feb 20 at 19:56
@grawity I guess it could be something like what this thread addresses.
– JakeGould
Feb 20 at 20:07
@grawity I guess it could be something like what this thread addresses.
– JakeGould
Feb 20 at 20:07
@JakeGould Thanks. Still unclear why the ISP is doing this instead assigning the IP address to the MODEM. But I'll delete since it's a dupe.
– MaxB
Feb 20 at 20:11
@JakeGould Thanks. Still unclear why the ISP is doing this instead assigning the IP address to the MODEM. But I'll delete since it's a dupe.
– MaxB
Feb 20 at 20:11
|
show 3 more comments
1 Answer
1
active
oldest
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Your modem is probably literally just a modem as far as IP is concerned. It doesn't have a public IP address assigned to it. When a device connects to your Internet connection, it has to establish a connection and the modem just translates signals. Your ISP sees the hardware address of the device that's connected to your modem and sees if it has a public IP address already associated with that hardware address.
answered Feb 20 at 21:33
David SchwartzDavid Schwartz
57k686130
add a comment |
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1 Answer
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Your modem is probably literally just a modem as far as IP is concerned. It doesn't have a public IP address assigned to it. When a device connects to your Internet connection, it has to establish a connection and the modem just translates signals. Your ISP sees the hardware address of the device that's connected to your modem and sees if it has a public IP address already associated with that hardware address.
answered Feb 20 at 21:33
David SchwartzDavid Schwartz
57k686130
add a comment |
Your modem is probably literally just a modem as far as IP is concerned. It doesn't have a public IP address assigned to it. When a device connects to your Internet connection, it has to establish a connection and the modem just translates signals. Your ISP sees the hardware address of the device that's connected to your modem and sees if it has a public IP address already associated with that hardware address.
answered Feb 20 at 21:33
David SchwartzDavid Schwartz
57k686130
add a comment |
Your modem is probably literally just a modem as far as IP is concerned. It doesn't have a public IP address assigned to it. When a device connects to your Internet connection, it has to establish a connection and the modem just translates signals. Your ISP sees the hardware address of the device that's connected to your modem and sees if it has a public IP address already associated with that hardware address.
answered Feb 20 at 21:33
David SchwartzDavid Schwartz
57k686130
Your modem is probably literally just a modem as far as IP is concerned. It doesn't have a public IP address assigned to it. When a device connects to your Internet connection, it has to establish a connection and the modem just translates signals. Your ISP sees the hardware address of the device that's connected to your modem and sees if it has a public IP address already associated with that hardware address.
answered Feb 20 at 21:33
David SchwartzDavid Schwartz
57k686130
answered Feb 20 at 21:33
David SchwartzDavid Schwartz
57k686130
answered Feb 20 at 21:33
David SchwartzDavid Schwartz
57k686130
answered Feb 20 at 21:33
David SchwartzDavid Schwartz
57k686130
57k686130
add a comment |
add a comment |
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1
When a computer is connected directly to the modem, do you see the same public address in the computer's own network connection info? For example in
ipconfigorncpa.cplor the Windows' settings app?– grawity
Feb 20 at 19:49
Are you sure you are not seeing a
10.x.x.xor192.x.x.xaddress when you use your router?– JakeGould
Feb 20 at 19:54
@JakeGould: It would be difficult for whatismyip.com etc to report such addresses...
– grawity
Feb 20 at 19:56
@grawity I guess it could be something like what this thread addresses.
– JakeGould
Feb 20 at 20:07
@JakeGould Thanks. Still unclear why the ISP is doing this instead assigning the IP address to the MODEM. But I'll delete since it's a dupe.
– MaxB
Feb 20 at 20:11