Reply
Visitor
KurtKalt
Posts: 3
Registered: ‎07-31-2011

new 3.0 modem - Cisco DPC3000 vs. Motorola SB6121

I want to purchase a new modem with DOCSIS 3.0 support and am looking for advice.  I read the list of modems approved by COMCAST California.  I am interested in Cisco DPC3000 and Motorola SB6121 but am open to other ideas.  I plan to use the modem with a Linksys e3200 router.  Thanks

New Visitor
Markusryan
Posts: 1
Registered: ‎09-16-2011

Re: new 3.0 modem - Cisco DPC3000 vs. Motorola SB6121

[ Edited ]

i just got Motorola SB6121 on tuesday 9/13/11 of this week and i am using the moden to day and it will work on the comcast service it is vary fast as well no problem. the tech just call tech seport and programe it to your account by phone.

Connection Expert
EG
Posts: 44,139
Registered: ‎12-24-2003

Re: new 3.0 modem - Cisco DPC3000 vs. Motorola SB6121

[ Edited ]

Both are very good modems. Choose either. The 6121 is more readily available at retail as the Cisco DPC 3000 used to typically be provided only by the ISP. The Zoom 5341 is also a good choice.

Visitor
KurtKalt
Posts: 3
Registered: ‎07-31-2011

Re: new 3.0 modem - Cisco DPC3000 vs. Motorola SB6121

Thank you for the advice.

 

What do you think about the Motorola SBG6580?  I notice that it received only 1 star on Comcast's list of certified modems (while the SB6121 received three stars).  The Motorola SBG6580 comes with 4 ports. 

 

Can I connect my Linksys router to this modem to:

1- get 8 ports 

2 - extend the range of my wireless network?  Can I connect the router to the modem in a different part of the house (using Cat5) and use it to setup a new wireless network for my backyard.    

 

Thanks,

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

Re: new 3.0 modem - Cisco DPC3000 vs. Motorola SB6121

[ Edited ]

I am personally not a fan of these gateway devices.  Comcast will be in control of the device's firmware, so you can't upgrade it if you need to.  One part goes bad, you have to replace the whole thing.  Performance and features are usually compromised in some fashion on these devices.  And connecting another router to a gateway usually results in a double NAT setup as well as all kinds of other subtle problems. Way too many cons more than offset the pros, IMO.

 

I would go with the Motorola SB6120 and your own wireless router, sounds like you already have a Linksys router.  If you need more ethernet ports on your router, simply connect an ethernet switch (of whatever size you need) to one of the available ports.  With seperate devices, you can place hte router when you want it and your modem where your coax feed is.  If you need to add an extender or repeaters, get one that works with your wireless router (these tend to be really picky about what works with what).

 

I have my own SB6120.  Connected to it is an Apple 1TB Time Capsule which only has 3 ethernet ports, so I also have a Netgear ProSafe GS108 (8-port gigabit ethernet switch) connected to the router.  Which gives me 9 free ethernet ports plus my wireless-N network, all flowing through the SB6120.

Visitor
KurtKalt
Posts: 3
Registered: ‎07-31-2011

Re: new 3.0 modem - Cisco DPC3000 vs. Motorola SB6121

Thank you everyone for your advice. 

 

As stated the 6121 is more readily available at retail so based on everyone's recommendation that is what I plan to purchase.

 

Thanks again. 

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

Re: new 3.0 modem - Cisco DPC3000 vs. Motorola SB6121


KurtKalt wrote:

Thank you everyone for your advice. 

 

As stated the 6121 is more readily available at retail so based on everyone's recommendation that is what I plan to purchase.

 

Thanks again. 


Not that there's anything wrong with the 6121, but the 6120 is just as available.  The differences are minor and mostly invisible to the user.  The 6120 is $11 cheaper on Amazon, at $76.37.

New Visitor
pyy72
Posts: 1
Registered: ‎10-23-2011

Re: new 3.0 modem - Cisco DPC3000 vs. Motorola SB6121

Can I use the SB6121 if I also have Comcast voice service?  I didn't see a phone jack on the back of this device.

Connection Expert
EG
Posts: 44,139
Registered: ‎12-24-2003

Re: new 3.0 modem - Cisco DPC3000 vs. Motorola SB6121

No. An eMTA needs to be used for their Xfinity voice service.

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

Re: new 3.0 modem - Cisco DPC3000 vs. Motorola SB6121


pyy72 wrote:

Can I use the SB6121 if I also have Comcast voice service?  I didn't see a phone jack on the back of this device.


No.  If you have Xfinity voice service, you have only one choice if you want to own your own EMTA, the Arris TM722G.  Comcast will only activate a user owned EMTA if you buy it from a Comcast kiosk in some Best Buy stores.  If you buy any other EMTA anywhere else, Comcast will refuse to provision it.