New Visitor
Posts: 1
Registered: ‎06-29-2011

Xfinity "wireless gateway" question.

So, I am used to having a netgear router where I know how to modify all the settings. Comcast decided to set me up with their wireless gateway router+modem combo when I had everything installed again (just moved, do not have my old took it back).




When hardwired to the router; my computer internet speed downloads up to 30-35mbps. My laptop, girlfriends laptop, and PS3 I notice that the speeds are around 3-8 (never surpassing 8). To me, it would make sense that I would need to manually change the channel to see if there is any interference. However, upon entering the gateway itself, there is NO option (at least that I can see) to do so.


I was on the phone with Comcast last night (HAHAHA) trying to see if any of them knew what could be the issue or how to actually change the channel. I had one person read me the instruction manual and two other people tell me that I should sign up for "Xfinity home support". To me, what sense does that make when they supply me with their own product, do not know any answers to the questions that I am asking, and want me to pay extra money for them to figure out how to use their own product?


Does anyone on these forums have any suggestion onto how my wireless speeds can be increased?


Forgot to mention...Signal is always over 80%


I guess I could mess around with firewall settings....heh



Thanks for any help!



Networking Expert
Posts: 24,238
Registered: ‎07-28-2003

Re: Xfinity "wireless gateway" question.

What gateway do you have?  Comcast has shipped several.  I think currently they are foisting the SMCD3GNV on TriplePlay customers.  To change the wireless channel on this device login into your router at and go the Gateway -> Connection -> WiFi page and press the EDIT button next to your wireless setup.  On the resulting page, set Channel Selection to Manual and then change the Channel number to whatever you wish and press the Save Settings button.  See page 18 of the manual for details.


There have been more than a few folks complaining about the wireless performance on this device, so that may or may not help.  If you decide to go with your own wireless router, call Comcast and have them put the device in Bridge mode (disabling the router function) and connect your own router to one of the LAN ports.  Any direct connected devices should be connected to the new router, NOT the gateway, only the new router should be connected to the gateway.


If you don't have the SMC, then please tell us the exact model number from the sticker on the back or bottom of the device.

Bronze Problem Solver
Posts: 685
Registered: ‎06-27-2006

Re: Xfinity "wireless gateway" question.

Posts: 6
Registered: ‎07-03-2011

Re: Xfinity "wireless gateway" question.

I have the new SMC gateway with an Xfinity triple play.  Have had for 3 weeks now.  The first week, it recognized devices that went onto the wi-fi network without skipping a beat.  Then the wi-fi home network was seen as not in range or not even identified.  I reseated the SMC and that seemed to solve it for awhile.  Then it wouldn't come up again for wi-fi devices in the house so I called tech support and they acquainted me with the reset button on the device.  Did that and it worked for 24 hours again before going out.  Reseated again and that solved it for another 24 hr. (more or less).  Since then have had to use some combination of these two to reboot the wi-fi daily.


Was told in chapter and verse by tech support on 3rd call that if I didn't have Comcast install a home wi-fi network I was SOL.  Had previously been with Verizon/Frontier FiOS with a gateway modem router for 2.5 years and NEVER had an issue.  Before that was with Comcast for 5 years and had a D-Link Router tied in with basic cable modem offered - again, NEVER an issue with wi-fi related to the equipment.


A home wi-fi network in this day and age is NOT rocket science.  So, on my last call to tech support (had a recurring TV channel problem), I was told that if I had a cordless phone within 2 ft. of gateway THAT could be a problem.  I have a 5.8 and I seemed to remember having read about this issue when I got the FiOS router but, upon review, it is 2.4 GHZ that was/is the problem.  I asked if DECT 6.0 might be beyond that issue and haven't done my research.  Anyhow, the SMC routers - I was told over and over by tech support - are NEW (at least in this market) and, to some degree, nobody has a clue how to troubleshoot or otherwise advise on any wi-fi networking problems.


So, I'm going into EVERY backup mode - tech coming today and we'll change out the gateway; purchased Motorola 6580 Docsis 3.0 gateway, unplug 5.8 GHZ cordless and see what exactly may resolve this.  Interesting that Verizon's Westell routers worked smooth as silk and the SMCs are bumpy. Did I mention that I work from my home?  Wi-fi is an important technological asset for me just as it would be for a business in a storefront or office environment.

Networking Expert
Posts: 24,238
Registered: ‎07-28-2003

Re: Xfinity "wireless gateway" question.

My advice, stay far away from gateway devices, they are nothing but trouble.  At the very least, have the SMC placed in birdge modem and use your own wireless router that YOU maintain.  Comcast is clueless when it comes to how to provide support for home networks, even when you purchase the service from them.  Far too many of their installers and techs are underskilled have no real understanding of networking and wireless issues.