Comcast Business Internet fixed IP address traffic performance vs dynamic IP traffic

Hello Tom and welcome to Comcast Business Forum and thank you for your post!

To answer your questions. When uploading large files that exceed the upload bandwidth, the gateway will utilize part of the download bandwidth in order to complete the upload.  This should not be a problem unless the upload exceeds the rated service level. In regards to a “fixed” IP address or a dynamic IP address, traffic are treated equally and do not receive a higher priority.

We always recommend keeping the network simple but giving your business needs we know at times this may not be the case. Comcast’s IP-Gateway will continue to lease LAN dhcp address as before introducing the fixed (static) IP address for your network.

Hope this helps

Jon,

Thanks for responding.

We have a premium circuit. The spec is 22Mbps/5Mbps.

I uploaded a 54 MB file to a Web site and got a 2Mbps upload speed, which is well under the 5Mbps spec.

I ran the Comcast speed test on the uploading computer and got 2.25 Mbps down and 1.58 Mbpsec up, showing that there was additional upload bandwidth available.

Another computer ran the Comcast speed test while the upload was going on, and got a download speed of .5 Mbsec. Sometimes non-uploading computers get 1-5 Mbpsec download speeds.

This doesn't seem right. It wasn't a perfect test as other computers are on the network attached to the Comcast router, but I will be running more formal tests to elimate those variables.

Is there any throttling going on that could explain  these results?

Tom

Tom,

I believe you are working with my colleague via PM, to address this issue.

Please continue do so.

Regarding "throttling" of connection, Comcast do not throttle connectives.

Thank You

Jon,

I think I may have found the source of the problem - the two affected users were connected to the SMC SMCD3G cable modem via a shared Ethernet switch, as there was only Ethernet circuit to their office.

I did simultaneous upload/download testing with two computers connected to two different ports of the SMCD3G. The problem didn't occur.

I ran another Ethernet cable for the second computer, so both users would have their own direct connection to the SMCD3G. No problem reports today. PowerBoost speeds of up to 35 Mbps on a 22Mbps/5Mbps circuit.

The SMCD3G user guide on page 15 states “Using an Ethernet LAN cable, you can connect the Gateway to a desktop computer, notebook, hub, or switch. Your Gateway supports auto-MDI/MDIX, so you can use either a standard straight-through or crossover Ethernet cable.”

This statement implies that it's OK to connect computers to the modem via a switch or hub, but this may not be the case. I emailed SMC support to see what they have to say, but haven't heard back yet.

Hopefully this wil resolve the issue.

Tom

Tom,

Thank you for the information. 

I hope your issue has been resolve with this change.

Thank You