I'm currently using the internet starter package with a static IP and am able to open/nat any ports I want for various services. I'm now considering switching to a dynamic IP with my own modem (Motorola SB6121). Assuming I have a router capable of port forwarding/natting, are there any restrictions different than when using the static IP service? Just want to be sure there's not any port blocking, etc. that will happen.
According to this post http://forums.businesshelp.comcast.com/t5/Equipment-Modems-Gateways/Static-IP-using-Motorola-SB6121-... static IPs are not supported on retail modems.
I have found no published restrictions other than the Microsoft ports blocked by every sensible ISP. And, port 0.
Incoming SMTP over IPv6 using port 25 is currently blocked. This is expected to be unblocked in a new software release according to a recent post on this forum.
I am running full dual-stacked using a Motorola SB6121 and an Apple Airport Extreme, coming up on two years of satisfactory service.
[UPDATE] Thanks to user train_wreck I now know of a published list:
On 10-05-2014, xz4gb8 wrote: [UPDATE] Thanks to user train_wreck I now know of a published list: http://businesshelp.comcast.com/help-and-support/i
[UPDATE 3-17-2017] The URL above no longer works. Use instead https://business.comcast.com/help-and-support/internet/ports-blocked-on-comcast-network/