Need Purchasing Advice

[frichardson]

So I went about this the wrong way - being too impulsive for my own good. I purchased a RT-AX88U that I may end up returning. In short I need to purchase:

• A DOCSIS 3.1 modem
• An AC wifi router

I have no clue about the modem, except that it has to work with RCN. I am currently renting their Arris modem/router which I want to return. Any advice on a good stable modem to go with would be great.

I have a AX88U in hand, but I am already thinking this was a mistake. The other two I've seen highly recommended are:

ASUS RT-AC86U (with RMerlin firmware)
NETGEAR R7800 (with Voxel firmware)

So I guess the questions are: which cable modem and should I hang in there with the AX88U or return it for one of these other ones?

EDIT: I just got RCN to disable the wifi on the Arris DG3450A modem I'm renting. I'm wondering if it's wise to stick with this modem since RCN has to support it...?

 

[RMerlin]

EDIT: ugh, these companies are slimy. Yes, looks like I can certainly buy my own modem and they are charging me a monthly fee for modem rental + wifi. $%&*#!

Double check with them. Some cable providers will only allow specific models/revisions on their network (when they do allow you to provide your own modem).

I've never been a fan of router/modem combos. They tend to do a fairly poor job on the router side of things, unless it comes from an already established router manufacturer like Netgear or Asus. If they are primarily a modem manufacturer, then the router side is just a "by-the-way" most of the time, and rarely get proper software maintenance to address security issues.

 

[RMerlin]

I have no clue about the modem, except that it has to work with RCN. I am currently renting their Arris modem/router which I want to return. Any advice on a good stable modem to go with would be great.

Get a list of approved modems from them first, as your starting point.

Personally I use a TC4400 here. I've had good experiences so far with Thompson/Technicolor's modems (having also used the DCM475 both personally and for various customers of mine). They tend to be a bit more expensive tho, and no idea if your ISP supports them.

 

[frichardson]

Double check with them. Some cable providers will only allow specific models/revisions on their network (when they do allow you to provide your own modem).

I've never been a fan of router/modem combos. They tend to do a fairly poor job on the router side of things, unless it comes from an already established router manufacturer like Netgear or Asus. If they are primarily a modem manufacturer, then the router side is just a "by-the-way" most of the time, and rarely get proper software maintenance to address security issues.

Thank you @RMerlin ! Yes, RCN was going to charge me $5/mo for wifi - so I got them to drop that... It turns out they use the same DOCSIS 3.1 modem and just disable wifi. So I still have a $6/mo modem rental charge. RCN is friendly to people who want to use their own DOCSIS 3.1 modem (BYOM), but there are issues with some models (they list them on the RCN web site) and I will be on my own keeping things working.

So, if the Arris is truely lousy then it may be worth buying my own modem, but for $6/mo the do have to support there modem...

EDIT: sorry for cross posting. I started up a new topic over in "Wireless Buying Advice" since that's really where I'm at with all this.

 

[beboptrumpet]

Thank you @RMerlin ! Yes, RCN was going to charge me $5/mo for wifi - so I got them to drop that... It turns out they use the same DOCSIS 3.1 modem and just disable wifi. So I still have a $6/mo modem rental charge. RCN is friendly to people who want to use their own DOCSIS 3.1 modem (BYOM), but there are issues with some models (they list them on the RCN web site) and I will be on my own keeping things working.

So, if the Arris is truely lousy then it may be worth buying my own modem, but for $6/mo the do have to support there modem...

EDIT: sorry for cross posting. I started up a new topic over in "Wireless Buying Advice" since that's really where I'm at with all this.

Get the Arris SB8200 instead of the combo device. It is a solid docsis 3.1 modem


Also, if they want to charge you, hang up ad call again until you get someone helpul. I am quick to start calling retention...say cancel service. Then explain that what needs to happen for you to come to an arrangement. I can usually tell if I should stay or hang up & try agai. in less than a minute on the phone. Usually only takes 1-2 times unless I’m hooking up TiVo & getting that billed right...that can take a minute

 

[RMerlin]

So, if the Arris is truely lousy then it may be worth buying my own modem

I was only referring to the router part. Arris has been in the modem business for a long time, so generally their modems are good (as long it doesn't use that dreaded Intel chipset).

 

[frichardson]

Thanks you @beboptrumpet and @RMerlin

The Arris SB8200 is currently selling for around 180 USD, so it would take almost 3 years to pay for itself at the current rental fee. I would consider it if the Arris router is a poor enough performer - stripping out their router is tempting.

 

[frichardson]

@RMerlin thank you for the Thompson/Technicolor recommendation - I don't see those modems around here. It looks like most of them are Motorola, Netgear or Arris.

I'm not sure how much of the gig internet download speed I'm really going to end up with. My upload speed is abysmal no matter what.

 

[Datalink]

You want to avoid any modem that uses Intel's Puma 6 chipset. Intel has pushed out updates to resolve the latency and Denial of Service issues with the Puma 6 chipset, but, its up to the ISPs to push those updates out to the modems. Several ISPs in the U.S. will not update owner operated modems, so, depending on your ISP, you might be out of luck if you buy an Intel Puma 6 modem.

The SB8200 is a Broadcom BCM3390 chipset modem, almost identical to the Technicolour 4400 that Merlin mentioned. That modem will keep you away from any Puma 6 latency and DOS issues and should provide many years of service. Just to note, no company, from Intel to the manufacturers to the ISPs have provided any latency plots, for IPV4 and IPV6 ICMP, UDP and TCP/IP that positively proves that all of the latency issues have finally been resolved.

Here's a couple of wikidevi links fwiw:

https://wikidevi.com/wiki/Arris_SB8200

https://wikidevi.com/wiki/Technicolor_TC4400

 

[frichardson]

@Datalink - thank you for that info - I will monitor how things go with the RCN Arris modem/router. I wonder if there is a performance hit simply having a second router in the path. If there is a way to turn it off or bypass it I will do that.

I have the RT-AX88U up and running and it seems to work out of the box (after an automatic firmware update). A fair number of things to try out now, but at least on two test sites over 5G I did get > 400mbps (wired directly to the Arris router I got over 800mbps).

 

[RMerlin]

If there is a way to turn it off or bypass it I will do that.

Ask your ISP if they support putting the modem into bridged mode. That would shift all the NAT/routing/DHCP duties into your router.

 

[frichardson]

Ask your ISP if they support putting the modem into bridged mode. That would shift all the NAT/routing/DHCP duties into your router.

Thank you @RMerlin, I will look into that.

In general do you recommend doing this or do you think it doesn't really make a difference?

 

[RMerlin]

In general do you recommend doing this

Yes. While it's possible to have two routers in front of one another (commonly known as "double NAT"), it's usually a bad idea. It will prevent UPnP-based port forwarding from working, and port forwarding have to be configured on both routers. Some particular applications like VoIP might also have problems working properly.

 

[frichardson]

@RMerlin, @beboptrumpet and @Datalink :

Thank you guys for the help, I think my way forward is clear: I'll either try to get RCN to reprovision my Arris dg3450a so it runs in bridged mode, or I'll buy the Arris SB8200. I'm actually leaning towards the second option because it may be difficult getting someone to throw the right switches over at RCN...

 

[frichardson]

Well, that was easy! I hooked up a cable directly to the Arris DG3450A and logged into the setup page. After scratching my head for a while found a button right in front of me titled something like "run in bridged mode". Throwing this switch seemed to do the trick.

The good news is that (at least according to speedtest.net) I get over 900Mbps wired directly to the modem - so in theory I'm getting what I paid for. My initial test with the AX88U over 5G is about half that so there is some work to do...

 

[EmeraldDeer]

Well, that was easy! I hooked up a cable directly to the Arris DG3450A and logged into the setup page. After scratching my head for a while found a button right in front of me titled something like "run in bridged mode". Throwing this switch seemed to do the trick.

The good news is that (at least according to speedtest.net) I get over 900Mbps wired directly to the modem - so in theory I'm getting what I paid for. My initial test with the AX88U over 5G is about half that so there is some work to do...

Half of 900 Mbps sounds about right for 2 stream 802.11ac 80 MHz wide

 

[frichardson]

Half of 900 Mbps sounds about right for 2 stream 802.11ac 80 MHz wide

With a little more tuning (i.e. following @L&LD and @RMerlin configuration notes) I'm at over 640Mbps.

So far so good!

EDIT:
@EmeraldDeer - looking at your signature, there are a few things I will try next (amtm, Diversion, etc). I might wait for the next RMerlin firmware release though - I'm not quite ready to try the beta version

 

[EmeraldDeer]

With a little more tuning (i.e. following @L&LD and @RMerlin configuration notes) I'm at over 640Mbps.

So far so good!

EDIT:
@EmeraldDeer - looking at your signature, there are a few things I will try next (amtm, Diversion, etc). I might wait for the next RMerlin firmware release though - I'm not quite ready to try the beta version

You may have devices which support 1024 QAM. If the Wireless Log Rx/Tx is higher than 866, that would confirm.

 

[frichardson]

You may have devices which support 1024 QAM. If the Wireless Log Rx/Tx is higher than 866, that would confirm.

@EmeraldDeer - how would I confirm that I have 1024 QAM? And what should I do to take advantage of it?

I saw this in the log:

May  5 05:05:06 kernel: dhd_runner_attach: Tx Offload - Enabled, Ring Size = 1024
May  5 05:05:06 kernel: dhd_runner_attach: Rx Offload - Enabled, Ring Size = 1024

Thanks for any help! =)

 

[frichardson]

Okay, I figured out a little bit. It looks like QAM is enabled on the unit - I'll check to see if my laptop supports it:

EDIT: Looking at my laptop, I have an Intel® Dual Band Wireless-AC 8260 adapter which I think goes up to QAM 256. Not to say I won't upgrade some day though