DOCSIS 3.0 Wired Routers

I would ask that question on the D-Link forums.

http://forums.dlink.com/

You will probably get a better answer there. I know the DAP-1360 I have is going back for a refund - it flat out doesn't work for the purpose I purchased it.

Thanks for the information. I'm going to go there and look around.

I would really like input from any users here who are using a DOCSIS 3.0 modem and wired router to tell me what setup they have and how satisfied they are with it.

I'm using the moto SB6120 on Comcast. It feeds a Linksys RVS4000 router. I use the router mainly for the firewall and dhcp - nat. I use managed switches to do the heavy lifting.

The 6120 definitly works better than the old docsis 1.1 modem we had!

So far no problems.

I'm also on Comcast and use the Motorola SURFboard SB6120 cable modem along with a Netgear WNDR3300 B/G/N capable wireless router and they work together with no problems. Have had them hooked up for months with never even one dropped connection.

We use it for connecting using both G and N speed laptops and it is very fast and even supports wireless N HD Netflix streaming to my Sony BDP-S570 3D wireless Blu-ray Disc Player.

k6rtm and rjrsw;

I thank both of you for your information. It seems I am making the correct choice with the modem.

I am using Comcast for my broadband and have an average speed of around 10 Mbps (with the new modem I'll see an increase of about 6 Mbps). I have this feeding 3 (sometimes 4) computers, a Roku, a 52" HDTV, a PS3, a Wii, a BD player and a Slingbox.

The modem feeds a Linksys wired cable router. One of the outputs of the router directly feeds 1 computer. A second output feeds a Netgear Powerline adapter which, in turn, feeds all of the other equipment through additional Netgear units. These units are all rated for 85 Mbps.

Since I am not having any issues with my current speed or setup I doubt I'll have any with the new modem and increased speed.

My only concern is my router. I believe it is too old to be DOCSIS 3.0 compatible so I have to consider a new one. I would rather it be wired instead of wireless.

Is your cable modem part of the router or are they separate devices? The throughput of your system to and from the Internet is limited to the slowest device - in this case the maximum bandwidth from Comcast - 16 Mbps. The rest of your network will be dependent on the rated speeds of the individual components and if your current router can handle 100BaseT, then you have at least 15 Mbps of headroom left for computer to computer communications.

Regarding the rated speed from Comcast, expecting your input to be 16 Mbps is only under optimal conditions which you will NEVER encounter. It assumes you are the only subscriber on your segment and there is no demand for bandwidth between you and the cable headend.

If your modem is separate, then changing it should not affect the other portions of the network - including the input to your router. 16Mbps is still WAY below even 802.11G speeds and upgrading to 802.11N is a waste unless you need that capacity as you are consistently transferring gigabit files between your computers and other devices on your network. In most home networks, anything above 802.11G is just wishful thinking as you don't have anything that will feed the network with that high of a bandwidth. We run an office of over 100 people with a 6 Mbps feed from our ISP.

Thanks for your reply. To answer some of your questions; The modem is separate from the router. The router cannot handle 100/BaseT. The 16 Mbps is a guess. I actually may get up to 22 Mbps. As I said before my only real concern is with the router.

SB6120 on Comcast. That modem feeds a newer Belkin N+ router which feeds an older Linksys WRT54xx. The Belkin provides an N exclusive network, the old Linksys provides a/b/g signal. I signed up recently for Comcast's Xfinity service, they quote my service at 15/3.

This setup has worked very well for the N network in that we are getting download speeds far in excess of the service quoted by Comcast. I sometimes see speeds up 60Mbps on the machines that can connect to the N network.

I have that Moto Surfboard 3.0 and have a Linksys Wireless route.

I'll have to check the actual model number.

The Netgear WNDR3300 B/G/N capable wireless router also has connections on it for 4 wired network connectors.

My Desktop is connected using a wired connection and everything else in the house is connected wireless.

Thanks for the info. I'll check into that router.

Unless you have an ancient router, most routers within the last 5 years should be able to handle DOCSIS 3.0 speeds just fine.

I have a Linksys BEFSR41. I believe I've had it since 2003 or 2004. From what I remember the specs on it are a 10 Mbps WAN port with 10/100 Mbps LAN ports.

While many Docsis 3 modems such as the Moto SB6120 offer gigabit ethernet, what matters is the speed you're getting down (and up) the cable.

If you are concerned that the equipment after your cable modem (router, switch, etc) is a bottleneck, you can check it:

Connect your computer directly to the cable modem -- you'll probably have to restart (power cycle) the cable modem. (NOT A RECOMMENDED CONFIGURATION!)

Run a speed test. I like http://www.speakeasy.net/speedtest/

Reconnect the modem to your other gear, power cycle it, and run the speed test from the same computer again.

If you're seeing approximately the same speeds, your router, etc., aren't causing you troubles.

As an example, I see download speeds reported from Speakeasy of 18 - 20 Mbps whether I'm directly connected to the cable modem, connected to the router, or connected over our 5GHz 11n wireless.

NOT A RECOMMENDED CONFIGURATION -- connecting your computer directly to a (cable) modem isn't the best idea, unless you have a very good knowledge of computer security and know how to harden the OS on the computer. A router, even an inexpensive one, provides a hardware firewall and other facilities (DHCP, NAT) to protect you from the nasties on the Net which are out there actively prowling for vulnerable computers.

Also, many ISPs, such as Comcast, limit the number of IP addresses you can have (Comcast lets you pay extra for more). Using a router presents one IP address to the cable modem, and supports all the rest of your gear on the other side.

That is kinda old but the specs on Linksys site says 10/100Mbps WAN port. Did you double check to be sure?

I have been using the Motorola SB6120 with a Netgear WNDR37AV router. My speed have increased significantly after upgrading both router and modem. I am also on Comcast, and can get 22Mb/s download and 8Mb/s upload. I think prior to upgrading my speed was about 1/2 that.

No I didn't check. I was trying to remember the specs from when I bought it.

What I've decided to do is try out the new modem (I should have it Wednesday) with the router and see how it goes.

If you were getting about 11 Mbps before your changeover that's right around what Im getting now (8 to 11 Mbps). I sure hope I see that much of an increase.

k6rtm, thanks for posting the information. I will try out your suggestions.

I received the modem yesterday. I won't be hooking it up until next weekend but I have a few questions.

Is there any compelling reason to install the software that came with this modem? I have never installed the software that came with any of my previous modems and have never had any issues in which I needed the software.

My plan is to disconnect the current modem, install the new modem, boot my computer, then, after the computer is running, power up the modem. I'll then call Comcast broadband tech support. I'll have the Mac Address, serial number and model number of the new modem ready for them. Is this the correct order or should I change or add anything to it?

Should I leave my wired router connected or should I go directly from the modem to the computer?

My main computer is running WinXP SP3 so I doubt I'll have any problems but I have a much older computer I still use that is only running Win98SE. I can currently connect to the 'net through the router using my current modem. What are the chances of still being able to connect once the SB6120 is installed?

I'll ask my son tonight when I pick him up, as he works at the English speaking Comcast call center.

Thank you. I appreciate it.

I would suggest making sure you have the customer serial number on the modem or if it doesn't say customer serial number it is the shorter of the two serial numbers. Also let them know the type of modem. It is best to have the modem directly connected to the computer first too so they make sure you are online right away, or if you do leave router plugged in make sure to reset it once they have added your modem to the system. I do also suggest calling the 1-800-comcast(2662278) anytime after 5pm. Usually get best support and less wait times after that point.

d-moo70, I have noted everything you told me. I will make sure I have all the needed information. Thank you.

In general, the software that is provided with the Surfboard cable modems (and other cable modems) is intended for if one is hooking the cable modem to your computer directly via USB--and honestly, seeing as all cable modems have a perfectly functional Ethernet port (and most PCs come with an Ethernet port) I see no real reason to use the software. (Even netbooks have Ethernet ports nowadays; the last time I honestly saw a PC without an Ethernet port was...oh, waaaaay back, I want to say around 2003 or so.)

With the Surfboard series in particular (which is highly recommended, and I'll toss in my own personal recommendation here--worked tech support myself and loved 'em when the ISP I worked for gave 'em out, and have pretty much consistently gotten Surfboards since I got cable modem service based on my experiences working tech support with 'em--they hang onto a signal like a pit bull and have useful diagnostic info for techs ) you certainly don't need the software if you're going to be hooking the cable modem up to the computer via a router and the Ethernet port; you can do the initial setup via web interface (if the 6120 is like previous Surfboards, you just go to http://192.168.100.1 and go from there).

Thanks for clarifying the software issue kusuriurikun. As I said in a previous post, I've never installed the software for any of my previous modems (2 SURFboard and 1 Cisco) so I didn't think I'd need it for the new one. I wasn't sure though because this is the first DOCSIS 3 modem I've owned.

Comcast activated my SB6120 about two hours ago. All I can say is wow!

Using http://speedtest.net/ as my test site for the past 1.5 weeks my average figures were;

Ping: 19 ms
Down: 9.5 Mbps
Up: 3.0 Mbps

With the new modem installed the new figures averaged;

Ping: 13 ms
Down: 24.97 Mbps
Up: 3.74 Mbps

The down and up averages stayed the same when I connected my existing wired router to the modem. The ping averaged 14 ms.

I never expected, in my wildest dreams, to get that much of a speed increase.

I have one more thing to add to the system and that is my Netgear 85Mbps Powerline Network Adapters. I don't think I'll have any issues with them, at least I hope not.

Thanks go out to everyone here who helped me. I'll keep all of you posted (no pun intended) as to what the final results are.

The results I got from your link averaged 24.98 Mbps down and 4.16 Mbps up.

Glad to see you up and running