On 12/14/2018 3:07 PM, VanguardLH wrote:
David E. Ross wrote:
On 12/13/2018 3:44 PM, VanguardLH wrote:
David E. Ross wrote:
Can someone explain why my modem and ipconfig give me two different IP6
addresses?
2605:e000:141e:c49f:8d8a:a676:3154:e70f (IP6) per IPConfig
2605:e000:c04:7b:e855:8b57:644f:706d (IP6) per modem
When logging into the web server internal to the modem to look at
devices, are you looking at the LAN-side (aka intranet) IPv6 address the
modem's DHCP server assigned to the device (or what the router reports
if the host uses if using static addressing), or are you looking at its
WAN-side IP address (the public address that all external/Intranet hosts
will see)?
https://www.google.com/search?q=what%27s+my+ip+address
Does that public IP address match on either the IPv6 addresses you noted
above? If so, that's the WAN-side IPv6 address of your router, not the
LAN-side IPv6 address of your intranet host.
When I go into my modem and click on the device listing for my host, its
IPv6 address, local link IPv6 address, and MAC/physical address match
what "ipconfig /all" reports on my host.
Do you have multiple NICs in your host? I don't have bother Ethernet
(wired) and wi-fi in my host, so I can't see how the modem reports the
different IP and MAC addresses for each NIC but I assume they would be
different. The PC came with a wi-fi daughtercard but I removed it
because it's a desktop, doesn't move, I prefer the simplicity and
security of a wired connection, and anything wireless that wants to
connect to my PC can do it through a wi-fi connect through the modem.
Configuration:
Windows 7 Ultimate SP1 (x64)
Motorola MB7220 V1.0 cable modem with firmware version 7220-5.7.1.9
Modem accessed through a Netgear N300 Wireless Router WNR2000v5
When I logon to the modem and request the advanced display, I can see
the following:
IPv6 Address 2605:e000:c04:7b:e855:8b57:644f:706d
Selecting the circled "i" for more information, I get:
IPv6 Address:
Assigned to your cable modem by your cable provider. The assignment is
referred to as a Lease.
IPv6 is a newer, longer style of IP Address. Your cable provider may
assign an IPv4 Address, an IPv6 Address, or both.
Note: Both IP6 addresses are "owned" by Spectrum, which is my ISP for
connecting to the Internet. (When connected, I use a different ISP for
E-mail and hosting my Web site.)
I'm assuming from your description that you have a separate router and
cable modem, not a combination modem that has a built-in router. If
they are separate, you have the config without the enclosing "combo".
.-----------combo(router+modem)------------.
|.-----router-----. |
host:IP---||--LANsideIP | .------modem------.|
|| WANsideIP --|---|---WANsideIP ||
|'----------------' | ISPsideIP --||---ISP
| '-----------------'|
'------------------------------------------'
There's the IP address of your intranet host.
There's the IP address on the LAN-side of your router.
There's the IP address on the WAN-side of your router. (*)
There's the IP address on the WAN-side of the modem. (*)
There's the IP address on the ISP-side of the modem.
(*) You won't see this in a combo (router+modem).
Unless you configured your host with a static IP address, it is
dynamically assigned by the DHCP server internal to the router. The
router's WAN-side IP address gets dynamically assigned by the modem's
internal DHCP server. The ISP-side IP address for the modem gets
assigned by your ISP's DHCP server.
I found your cable modem at with pics:
https://www.amazon.com/MOTOROLA-Cert.../dp/B019ZY1ZWS
The backside has only 1 Ethernet port, so it is usable with only a
single intranet host or you connect it to a router to hookup multiple
intranet hosts. Since it appears you are using a separate router, my
guess is:
- The WAN-side IP address of your router comes from the cable modem's
internal DHCP server.
- The ISP-side IP address of the cable modem comes from the ISP's DHCP
server.
- Both those IP addresses come from your ISP's IP pool.
- They need not be the same. The cable modem's IP address allows tech
to access the cable modem, like when provisioning it, not something
beyond it. They probably don't care/support what you have on the other
side of their modem.
Since the router and modem are separate network devices, they each need
an IP address on their interface to connect to each other. The WAN-side
IP address of the router connects to the WAN-side IP address of the
modem.
.---router----.
|--LANsideIP | .----modem----.
| WANsideIP--|---|--WANsideIP |
'-------------' |ISPsideIP --|
'-------------'
Does your router report the modem's WAN-side IP address? If your router
is configured for dynamic IP address assigned (from the modem's internal
DHCP server), it should list what is its "gateway" IP address (where to
find the modem but its IP address).
It is almost dinner time. After dinner, I will reconfigure to have my
PC connect directly to the modem without the router. That can be only
temporary because my wife's PC also connects to the router to reach the
modem and then to the Internet. This is described at
http://www.rossde.com/computer/LAN.html.
I generally avoid combination devices -- router-modem, printer-scanner,
etc -- because subcomponents rarely fail together. I am concerned that
Southern California Edison's momentary spike might cause only the router
part of a router-modem to fail. If that happens with separate modem and
router, I could still connect directly to the modem until I can replace
the router. This indeed happened.
--
David E. Ross
http://www.rossde.com/
"President Donald Trump said on Tuesday [11 December] that
U.S. authorities had 'caught 10 terrorists', ... but four
government sources said there was no recent evidence of terrorism
suspects being caught along the border." Reuters News
I think Trump is the primary source of the fake news he condemns.