Not sure how or why I have 2 IP addresses with Spectrum that work

[rigurat]

I have an Arris SB8200, purchased not provided by the ISP, it has the older firmware that does not support link aggregation. It has two WAN ports. I have a pfSense router and out of curiosity plugged that second WAN port into the router. To my surprise the router is showing me a second IP addresses, another IPv4 and IPv6 address. I can confirm that second IP address works, I was able to dynamic DNS it and log into my NAS with it.

Is this some sort of oversight from the ISP? I thought ISP's don't give second IP addresses to residential customers.

I am on Spectrum standard residential internet in Hawaii.

 

[SamirD]

Not necessarily an oversight as a lot of ISPs would allow you to pull multiple public IPs if you had a switch on the connection. Usually they top out at 2x though.

More of an edge case that they missed since they probably never planned for a CPE modem to request more than a single IP from a single device, which the 8200 can do.

Having a second IP like this can be handy for sure, especially when the second IP is on a completely different route. But if there's an actual node or signal issue, both connections will go out.

Now, here's the kicker that you may not realize--you may be getting 2x the bandwidth, one via each connection. I would connect individual devices to each IP and run simultaneous speed tests and see what you get. If both are hitting your paid plan, then congrats, you've got a multi-wan setup in the waiting.

 

[German Muscle]

What modem do you have? What level of internet service do you have?

I know spectrum gives everyone two IP reservations for when the downstream MAC changes but usually the ip range is fairly close and wouldnt be a 66.xx.xx.xx and a 50.xx.xx.xx

If your using the two outputs on your cable modem and getting IPs like that then it could be because thats how they provision modems with two ports now. If thats the case ill go ahead and plug in my second port on my modem and get another IP and i can route all my home traffic through my normal IP and use the other IP for routing traffic for my lab.

a lot of ISPs would allow you to pull multiple public IPs if you had a switch on the connection. Usually they top out at 2x though.

Spectrum doesnt do that and ive not really heard of any of the large ISPs that support connecting a modem directly to a switch.

 

[rigurat]

What modem do you have? What level of internet service do you have?

Arris Surfboard SB8200, not provided by ISP and has the older firmware that doesn't support link aggregation for single WAN. I'm stuck with that firmware because Arris doesn't have any firmwares on their website, I can't find any way online on how to user update the firmware and Spectrum does not push firmware updates on customer purchased modems.

Internet is Spectrum 500mbps internet, residential class, in Hawaii.

 

[SamirD]

Spectrum doesnt do that and ive not really heard of any of the large ISPs that support connecting a modem directly to a switch.

I personally haven't tried it with any of our spectrum accounts, but I know that's exactly how I had a server set up on a previous isp that was gobbled up by another. Back in the day before consumer routers with nat were common, a switch and static ips were common--that's how our first ISDN bonded internet worked on our ascend pipeline 50.