Modem cable connection device
Modem cable connection device
It seems better to purchase a new modem and connect your router, as Optimum doesn’t recommend it for this setup. Using an Optimum gateway would be unnecessary since you’re already on cable with 300Mbps speed.
A gateway combines a modem and router in one device, meaning unless it's operating in bridge mode, you're effectively using double NAT. I own a CM1000v2 through Comcast. It performs well, and they charge $15 monthly for their gateway, making it a clear choice. I recommend checking if Optimum lists supported modems. No matter the service tier, I’d get a Docsis 3.1 unit. They’re available in two versions: one with Gigabit Ethernet capping around 940 Mbps and another with 2.5 Gbps Ethernet supporting multiple gigabit speeds. That will depend on your future speed needs. My CM1000v2 only has a Gigabit port, so we won’t pursue the premium plans since Comcast keeps prices low.
Optimum support indicates they switched it to bridge mode... I can't verify that. I was checking the Arris S33. The wireless router currently has a private WAN IP address. It's possible this device is operating in a multiple-NAT setup. Using an external check could update DDNS with the right IP, but it might still affect remote access. I don’t recall how to confirm double NAT status.
When the WAN IP is in a private range, you're likely using double NAT. The S33 works well, and Comcast offers the fastest download speeds. Mid Split support isn't clear—I'm not sure about higher upload capabilities.
The S33 doesn't handle the faster upload rates well, unfortunately. It's also prone to overheating easily. It's not a major issue, just a restart will help, though I haven't used a modem that's this sensitive to temperature before.