Comcast XFINITY → [IPv6] IPv6 shows I'm coming out of New Jersey?!?

This is the first time I've seen this IPv6 address come up. Only reason I know of this is because I saw an email from FB telling me someone logged in from some city near New Jersey... So of course I changed me PW and when I got the email about the change, it also showed that the state was New Jersey.

whatismyip shows the IPv6 address, as well as a few other sites. Only google and the forums I visit show the correct IP that I am used to seeing..

I've tried resetting the gateway, even talked to comcast support, which told me to do it via CMD, so I did and nothing changed.

I'm confused as to what is going on! I don't want important sites to think someone from New Jersey is accessing my accounts, when I am in Indianapolis!!!! Can someone help me figure out what is going on please!

I'm confused by what you mean by that. Are you referring to one of the IP addresses you are allocated (a residential customer generally gets 1 IPv4 address and 18,446,744,073,709,551,616 IPv6 addresses, of which a typical Windows machine will use 2 of those 18,446,744,073,709,551,616 addresses but will communicate over the Internet using only one of those public IPv6 addresses.

Or are you referring to what geographic location a particular web site's geolocation service places your IP address?

By the way, I noticed a few days ago in checking geolocation, that the IPv4 address seems to resolve to the correct city (though they vary on where within the city I am located), but the sites have wide variation on where they think my IPv6 address is located, some (like you noticed) placing it in New Jersey with the correct ISP (and Oregon is quite a ways away from New Jersey), some place it in the correct state but with the wrong ISP, and the minority actually place it in the correct state with the correct ISP, though even those, half the time, get the city wrong by 40 miles or more.

In a case like yours, I think I would complain to FB about their geolocation getting the address wrong, and as more and more customers complain about that, hopefully eventually they will start applying pressure on their geolocation service to fix that problem.

I don't see how this is a Comcast problem since they are in the market to provide Internet services and their responsibility ends with issuing a suitable IP address. And quite frankly I don't see this as your problem other than Facebook issuing a fictitious warning. And as part of your argument to Facebook can be the sites that geolocate you to the correct state (and maybe even to the correct city) so that is evidence that you and Comcast have your parts correct, not Facebook.

Just for that, I'm going to log off of Facebook and log back on, so I can see if they get my location wrong by 2,900 miles (the distance from Salem, Oregon to Mount Laurel, New Jersey).

I logged off of Facebook, logged in to Facebook using IPv6, clicked on the Privacy padlock icon, clicked on "See more settings" at the bottom of that pop-up menu, clicked on "Security" in the left navigation area, clicked on "Where you're logged in".

It shows:

Current Session
Location: Unknown
Device type: Firefox on Windows 7

So I guess I don't get to participate in Facebook's finger pointing.

whatismyip is showing 2403:781:b148:938:195d:962:shl4:2efc (not my real IP I see, but it looks just like that). Also, while looking at the IP info, I show the same Mount Laurel, New Jersey is what it claims. I understood some of what you said lol, just trying to wrap my head around how all of a sudden I've got an IP out of Mount Laurel, New Jersey.

You PC most likely has more then 1 global IPv6 address, a SLAAC IP and a DHCP IP.. Both of these will work..This is because the geolocation server is using whois to find out where you are.. do a quick google for geoip or geolocation ip..

That looks like an IPv6 address. My IPv6 address is currently 2601:1c1:123x:567x:b834:f36d:2bb9:285 (using "123x:567x" to mask out part of the address, but leaving enough that I can discuss the breakdown of this IP address.)

2601:1c1 is in the range 2601:1c0:0:0:0:0:0:0 to 2601:1ff:ffff:ffff:ffff:ffff:ffff:ffff, which is in one of the blocks of IPv6 addresses allocated to Comcast, this range being for Beaverton, OR, which is about 35 to 40 miles south of my physical location. (That explains why some geolocators locate me in Beaverton, OR instead of in Salem, OR.) However, the administrative address that who-is has on file (not the location of where that IP range is used, but where business offices are located) is in Mount Laurel, New Jersey. (Does "Mount Laurel" sound familiar? ) Anyway, this is the link to ARIN's who-is page where I am getting the above information.

Comcast then takes that block of addresses,
from 2601:1c0:0:0:0:0:0:0
to 2601:1ff:ffff:ffff:ffff:ffff:ffff:ffff
and suballocates from that to their various devices (servers, routers, etc.) and customers located within a certain "distance" from Beaverton, Oregon.

2601:1c1:123x:567x becomes the block of public IPv6 addresses that Comcast delegates to me. (Again, the 123x:567x is being used here to mask my actual IPv6 address.). When I look at the router side of the gateway, I see that the "Delegated prefix (IPv6)" is 2601:1c1:123x:567x::/64

I as a customer then can theoretically use any of the public IPv6 addresses in that block of delegated addresses at 2601:1c1:123x:567x::/64, one or more public IPv6 addresses:
from 2601:1c1:123x:567x:0:0:0:0
to 2601:1c1:123x:567x:ffff:ffff:ffff:ffff

When Windows 7 starts up and starts communicating on the network card (my reading has been on Windows 7 since that is what I run), it goes through a series of steps and gets an IPv6 address, and then it goes through another series of steps to get a second, "temporray" IPv6 address that it will use over the network (i.e., over the Internet).

So now my PC two public IPv6 addresses:
2601:1c1:123x:567x:xxxx:xxxx:xxxx:xxx (using x's to hide)
2601:1c1:123x:567x:b834:f36d:2bb9:285 (temporary)

My PC also has a link-local IPv6 address starting with fe80:, but that address is never seen on the Internet side.

Windows then favors the use of that temporary address when communicating over the Internet. On the next reboot or when the temporary address expires, a new temporary address will be used, but still within the range of addresses Comcast has delegated to my residence (rather, to the router side of the "gateway" Comcast has issued to me).

Oh yes, my residence (again, the router side of the "gateway") is also delegated 1 public IPv4 address, in my case of the form 71.193.xxx.xxx with the range 71.193.128.0 - 71.193.255.255 belonging to Comcast allocated to "Oregon-18", but again with the administrative address in the who-is being given as Mt. Laurel, NJ. Since there are multiple IPv4 devices, the router sets up local addresses (typically 192.168.x.x, but in the case of these Comcast gateways it is of the form 10.x.x.x, more specifically 10.0.0.1 for the router, 10.0.0.2 for this PC, and so on for my other IPv4 devices on the local area network) and performs Network Address Translation (NAT) when any of these devices use IPv4 to communicate to the Internet, so on my local area network my PC is 10.0.0.2, but when it communicates to an IPv4-only web site, the router converts the address so it appears to that web site that the packet is coming from 71.193.xxx.xxx, sends its reply back to 71.193.xxx.xxx, and the NAT tables in the router then know to forward the reply packet to 10.0.0.2 on the local area network so my PC knows the packet is for it.

So, when I browse various web sites, they will see one of two IP addresses from me:

71.193.xxx.xxx if using IPv4 (PC thinks it is 10.0.0.2; Network Address Translation in the router translates the packet addresses as they pass from LAN to the Internet or back.)

2601:1c1:123x:567x:b834:f36d:2bb9:285 if using IPv6 (same IPv6 address from Firefox all the way to the server, which is why it's good to have a stateful firewall to block unsolicited packets, but IPv6 has several other advantages beyond the scope of this thread, the most pressing one is that ARIN ran out of IPv4 addresses but IPv6 addresses are quite plentiful.)

It is possible for some web pages to be fetched using both IPv4 and IPv6 since different parts of the web page (style sheet, pictures, video and sound files, advertisements, etc.) may reside on different servers, which might be resolved to IPv4 addresses or IPv6 addresses and might not match the protocol used for fetching the main file for that web page. For example, Netflix DVD title pages are served from dvd.netflix.com, which is IPv4-only and sees my PC as 71.193.xxx.xxx; but the cover art is served from cdn-0.nflximg.com, which supports both IPv4 and IPv6, and, since I am dual-stacked IPv4 & IPv6, the image file is fetched using IPv6 and cdn-0.nflximg.com sees my PC as 2601:1c1:123x:567x:b834:f36d:2bb9:285, at least for today. (After next reboot or when the temp IPv6 address expires, it would see this PC as 2601:1c1:123x:567x:something-else.)

Anyway, the "Mount Laurel, NJ" is because the administrative offices of Comcast, at least the offices for requesting and maintaining the IP addresses used by Comcast, are located in Mount Laurel, NJ, and some geolocation services are looking at that rather than where different sub-blocks are actually used.

I don't know about you, but I got a better picture of how some of this ties together (or produces misinformation) when researching the answer to your question. Thank you for asking!

Confirmed. I did a reboot and the last half of the IPv6 address the PC is using to access the Internet (the "temporary" IPv6 address) changed.

Still, this shouldn't affect geolocation since geolocation should be looking at the left portion of IPv6 address, which did not change.

I personally found this website to be really cool at showing location for both the IPv4 and IPv6 address via links in the blue addresses. »ipv6-test.com/