Ports being filtered to my Xbox and Port Forwarding has seemed to no longer work after the...

As you noted, a port can only be forwarded to one IP. When you manually forward ports to Xbox A, those ports are no longer available to be forwarded to Xbox B. Placing Xbox B in the DMZ will not help because doing so essentially just forwards all available
ports to Xbox B, and the needed ports are no longer available because you forwarded them to Xbox A. The only way to get open NAT on both at the same time is to use UPnP on a good router that has a working UPnP implementation (many home routers don't). To
try it, enable UPnP on your routrr and remove all Xbox-related port forwards and DMZ.

Sure it's a xfinity technicolor tc8305c gateway.

I've got the ports forwarded on my Xbox, however it seems I can't port forward the same ports for his Xbox one.

Currently my Xbox one has all the ports forwarded and I have an open NAT. He has none with a strict NAT.

Then your router has working UPnP, which the Xbox One is using to automatically forward the needed ports. Or, more likely its UPnP is somewhat broken or slow to respond, and each time you do the "fix" the Xbox repeats the UPnP port forward request and after
enough time the router responds and forwards the port (at which time the One reports open NAT). The point is, if you truly have open NAT, the required ports are in fact being forwarded to your One by some method, either via UPnP or manually.

They is a Option COuld Port triggeing which is just like port forwarding. They is Also a Option for Port forwarding. Here are all the options i Get

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Greetings Malacath!

Before we get started, could you post up the make and model of your modem and your router.

[quote user="Malacath"]I have just done a factory reset of the xbox to see if that would fix the UPnP but now when I do the multiplayer test then press all the triggers it says i'm behind a cone nat.[/quote]"Cone NAT" means that you have an Open NAT.

The terminology "Cone" is no longer being used by STUN utility tool, (Session Traversal Utility for NAT) according to IETF (Internet Engineering Task Force) to describe mapping and filtering behavior, as this has been the source of too much confusion. The new
terminology to describe NATs mapping and filtering behavior: Endpoint-Indepedent mapping and filtering, Address-Dependent mapping and filtering, Adress and Port-Dependent mapping and filtering.

[quote user="Malacath"]I've forwarded ports 3074 and 3075 and now my NAT is open but the network test still says cone NAT.[/quote]Which ports have you manually forwarded for respective console (Xbox One, Xbox 360)?

You can't manually forwarding port 3074 for the Xbox One, as this is the port your Xbox 360 uses for xbox traffic.

Sidenote: I assume port 3075 and 3076 are the ports Xbox One uses if port 3074 is not available, as the fall-back mechanism.

[quote user="Malacath"]Can network guru please explain what cone NAT means and whether it is a problem?[/quote]If your Xbox One refer your NAT's behavior as "Cone NAT", then you have an Open NAT/Full-Cone NAT/Endpoint-Independent mapping and filtering. Its
the same behavior, different terminology.

Whenever an application on your console (eg. Halo) opens an outgoing session through your router/NAT, your router/NAT assigns the session an IP address and port number. This IP and Port will be public and thereby routable out on the Internet to an external endpoint
(eg. LIVE server's IPort), so that packets being sent to the external endpoint, can also be received, translated and forwarded to your console (internal endpoint, IPort). This relationship creates a mapping between the internal IPort and external IPort.
Note! The external IP and port is not the same thing as an external endpoint, but the relationship between your router's and your console's IPort tuple.

The key for your router/NAT is to reuse the mapping, whenever an application on your console initiate a new session to an external endpoint. This behavior is crucial when you have multiple simultaneous sessions running on your console to different external
endpoints. For example, you play Halo on your console and receives an invite to join a party with your friends.

There is also an entire topic how ports are being assigned and its behavior, but that's another story.

Open NAT/Cone NAT/Endpoint-Independent mapping and filtering behavior means that the mapped ports are being "opened", either permanently, if you use Static NAT/Port Forwarding, or "opened", for the duration of each session until the timer reach 0, if you use
UPnP (Universal Plug and Play). This allows, an independent host on the external side, to send data to the reused mapping of your router/NAT, translated and forwarded to your console (internal endpoint, IPort). It will only allow traffic
to pass through to the same port number(s) or data/packets will be dropped/filtered.