Recently comcast had us upgrade to a Arris TG1682G modem/router. Afterwards we have had trouble with multiplayer on our Xbox one, specifically we always seem to have a moderate NAT and nothing we try will give us an open NAT.
We currently have the xbox in DHCP with UPnP enabled. We have also tried port forwarding, putting the xbox into DMZ, and anything else we could find in the numerous online posts about xbox and NAT.I am not confident that we were able to adequately try DMZ and port forwarding since neither the modem nor xbox seem to have an option to disable IPv6 and the last part of the Xbox's IPv6 address changes everytime it restarts.
Download speed, upload speed, latency are all fine and we have 0% packet loss.
Thanks again, but I have gone through everything in the various online guides several times unfortunately. Port forwarding, port triggering, or DMZ all produce a consistent Moderate "Port Restricted" NAT. UPnP a consistent Moderate "UPnP Port Restricted" NAT. I should also mention that things have been fine on the xbox for years prior to this issue. Have also tried different ethernet cables, including a brand new one. I did try using comcast support, they went in and re-enabled my port forwarding settings, (but left UPnP on,) and had me power cycle the modem and do several hard resets on the xbox. This didn't change anything but they didn't have anything to offer beyond that. There are several other UPnP settings mentioned in some online posts but I can't try those since this modem does not seem to have them.
I am even more confused since, with the new modem, the xbox is now using IPv6.
I had this same problem and this website has the prts and information necessary to make your NAT=OPEN
Essentially I had to just do the following:
a. reserve my Xboxone's Ip in my comcast modem
b. Under advanced setting; enable port forwarding
c. add these rules for the proper ports (be sure and select TCP or UDP or both as per the instructions in the URL)
Not sure if you've solved your problems yet, but I recently went through this with my Xbox One after upgrading to a new Xfinity Gateway. I was getting dropped from games and group chat constantly. Basically, it was unplayable.
I tried all the fixes mentioned above, and it never worked. But, once I put my Xfinity into "Bridge" mode, and then hooked up my wireless router to it, everything has been fixed. Bridge mode basically turns off the wireless capabilities of the Xfinity Gateway and makes it just a modem.
It's like night and day. I have a really nice ASUS wireless router that has all the settings you need to make the Xbox One work perfectly.
Best of luck.