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espaeth
Digital Plumber
Premium,MVM
join:2001-04-21
Minneapolis, MN
kudos:2
Reviews:
·Vitelity VOIP
reply to NetFixer

Re: [Business] [POLL] Do you have the new 15/3 or 27/7 business

said by NetFixer:

While the ratio of real techs to script readers is better with business class, it's still the luck of the draw when you call for support.

There was a noticeable drop in quality of rep when they centralized business support. The local Minneapolis support team was awesome, back when they existed.


pflog
Bueller? Bueller?
Premium,MVM
join:2001-09-01
El Dorado Hills, CA
kudos:3
reply to pflog

I believe I misunderstood the person about the Netgear they mentioned.

It sounds like it could be a new device I guess? It wouldn't make sense for them to offer the Netgear 8013/8014, since neither of them is DOCSIS 3 capable and I doubt they could do 27/7 reliably.
--
"Women. Can't live with 'em, pass the beer nuts." -Norm



NetFixer
From my cold dead hands
Premium
join:2004-06-24
The Boro
Reviews:
·Cingular Wireless
·Comcast Business..
·Vonage
·Comcast

Netgear does have a commercial grade DOCSIS 3 cable gateway box:
»www.netgear.com/service-provider···CR.aspx#

Not much information on the Netgear web site since it is apparently only sold to service providers, so Netgear doesn't feel that there is a need for potential end users to know very much about it.
--
We can never have enough of nature.
We need to witness our own limits transgressed, and some life pasturing freely where we never wander.



EG
The wings of love
Premium
join:2006-11-18
Union, NJ
kudos:9

FWIW, that device does not yet appear to be on their *Approved Modems List*.


biomesh
Premium
join:2006-07-08
Tomball, TX

said by EG:

FWIW, that device does not yet appear to be on their *Approved Modems List*.

It has for the last few days:

»mydeviceinfo.comcast.net/device.···so=&sc=0


NetFixer
From my cold dead hands
Premium
join:2004-06-24
The Boro
Reviews:
·Cingular Wireless
·Comcast Business..
·Vonage
·Comcast

1 recommendation

reply to EG

said by EG:

FWIW, that device does not yet appear to be on their *Approved Modems List*.

True, but there are no Netgear modems or gateways on the business class approved modems list, and apparently someone from Comcast has proposed using a Netgear box to solve the problem being seen by pflog.

It is possible that this Netgear box may be under testing and consideration as a replacement for the SMCD3G-CCR which is apparently not being very cooperative in working with Comcast's native IPv4/IPv6 dual stack.
--
We can never have enough of nature.
We need to witness our own limits transgressed, and some life pasturing freely where we never wander.


NetFixer
From my cold dead hands
Premium
join:2004-06-24
The Boro
Reviews:
·Cingular Wireless
·Comcast Business..
·Vonage
·Comcast
reply to biomesh

said by biomesh:

said by EG:

FWIW, that device does not yet appear to be on their *Approved Modems List*.

It has for the last few days:

»mydeviceinfo.comcast.net/device.···so=&sc=0

Yep, I had to refresh my browser's cache to get it to show up in the main business class list, but it is now on the approved list. Strange that it does not yet appear to support IPv6; I would have thought that would have been a high priority requirement for a new device on the approved list.
--
We can never have enough of nature.
We need to witness our own limits transgressed, and some life pasturing freely where we never wander.


EG
The wings of love
Premium
join:2006-11-18
Union, NJ
kudos:9
reply to biomesh

Thanks for the correction. I will assume that they then have a configuration file for it so that it functions on their system ?


GusHerb94

join:2011-11-04
Chicago, IL
kudos:1
reply to pflog

I rebooted the SMCD3G at our shop today and we have the new speed!:

"Estimating capacity:
Upstream: 3978 Kbps.
Downstream: 20856 Kbps.

The measurement will last for about 2.5 minutes. Please wait.

Checking for traffic shapers:

Upstream: Burst size: 7060-7098 KB; Shaping rate: 3173 Kbps.

Downstream: Burst size: 9899-10028 KB; Shaping rate: 17024 Kbps.

For more information, visit: »www.cc.gatech.edu/~partha/diffprobe
logout

[Process completed] "

Looks like it's 17/3 for us! Also one thing I noticed is that the Powerboost is no longer unthrottled, before i was getting up to 50 MBps upload with PB



JohnInSJ
Premium
join:2003-09-22
San Jose, CA
reply to NetFixer

said by NetFixer:

said by WheatridgeCO :

SMC D3G Hardware Version 1.01 / Firmware Version 1.4.0.49.7-CCR / Running in Bridged mode with 5 Static IP's thru a Cisco Pix 525

Is this a new connection? I was not aware that Comcast allowed that configuration. I was told that you had to use an SMC gateway in gateway mode in order to get static IP addresses.

Or are you confusing not using the SMC's NAT with bridge mode. Unfortunately, that is something that a lot of uneducated (and/or unethical) Comcast CSRs seem to do, and their referring to doing that as bridge mode in turn confuses a lot of customers.

He means "true static" mode - that's normal with static IPs - its the same config I use with my static IPs
--
My place : »www.schettino.us


JohnInSJ
Premium
join:2003-09-22
San Jose, CA
reply to NetFixer

said by NetFixer:

said by pflog:

He then went on to ask me what the problem was, and he said something like "the DNS server is not set, I will enable that and it will fix your problem".

I've gotten that same advice too, and also have been told that the SMC gateway will not even work unless you enable its DHCP server, and that the SMC gateway's 1-1 NAT was the only way you could use your static IP addresses.

said by pflog:

Naturally, it didn't fix the problem. Then he asks where I'm testing from and I tell him various mirrors and he tells me "engineering requires you to test from speedtest.comcast.net to get an accurate speed result". SIGH, and I was just talking about how the business class support reps were more knowledgeable.

While the ratio of real techs to script readers is better with business class, it's still the luck of the draw when you call for support.

that's not even remotely correct - you can use true static mode with static IPs. Your static IP is routed thru the modem. It's a standard config
--
My place : »www.schettino.us


WheatRidgeCO

@comcastbusiness.net

said by JohnInSJ:

said by NetFixer:

that's not even remotely correct - you can use true static mode with static IPs. Your static IP is routed thru the modem. It's a standard config

This is TRUE for STATIC IPs, EVERYBODY, all you need to do is set Disable Firewall for True Static IP Subnet Only / Disable Gateway Smart Packet Detection on the firewall page, and then
use YOUR OWN ROUTER, and Do not use DHCP to get IP address from the SMCD3G, put in the REAL STATIC IP address in YOUR ROUTER, and the SMC will pass all traffic straight thru. (This way your only NAT'd once, as long as you set that up inside YOUR OWN ROUTER. Not that hard to setup traffic rules inside Cisco routers, and almost any security appliance with NAT cabability will work well. We let windows assign DHCP addresses on the LAN side, the Cisco/Security appliance only needs to know what the
address range is. We do not let the Cisco/Security appliance divy out DHCP addresses, even though it can. In a Windows-Server enterprise its better to let it keep track of DNS/DHCP that way it keystones everything and integrates better with Active Directory.

Another thing I do at our office is this :
I connected a cheapy Netgear wireless router directly to one of the 4 ports on the SMCD3G, and I set it up to get a DHCP address from the SMCD3G 10.1.10.X address and I let guests that visit our office use the netgear for internet access, and that keeps them off of the LAN side of our Cisco PIX thus securely on the otherside, just like any other internet user would be. This also makes a nice way to test Cisco VPN Tunnelling software inside our office, thru the Cisco firewall.

There is one more great benifit of setting this type of IPV4 setup, if you ever change providers, then you will only need to make minimal changes IN YOUR OWN ROUTER. all internal IP's would never change, thus no more changing the entire enterprise's IP addresses, as you would keep the NAT'd IPs that you setup in your OWN ROUTER. Change your domain records, update your DNS records, change the static IP in YOUR OWN ROUTER. and the whole change to a new provider would be done quickly.


noc007

join:2002-06-18
Cumming, GA
Reviews:
·Comcast

1 edit
reply to pflog

Cumming, GA
SMC D3G
Old: 12/2
Apparently new: 15/3

This past summer, my speed tests were looking like this:



I call BS on the accuracy of the results since my real world usage of downloads and uploads supported the bottom tier I'm on with PB being quite high. When I first signed up, my speed tests had PB pegged usually around 75/40. I don't have a shaperprobe log for this time period though.

Now my speed tests are more like this:


Based on real world usage and speed test this is relatively accurate and my PB has definitely been lowered, especially the upload, like others have reported.

Here is the shaperprobe I took today:

DiffProbe release. January 2012. Build 1008.
Shaper Detection Module.
 
Connected to server 38.107.216.34.
 
Estimating capacity:
Upstream: 4012 Kbps.
Downstream: 21497 Kbps.
 
The measurement will take upto 2.5 minutes. Please wait.
 
Checking for traffic shapers:
 
Upstream: Burst size: 4939-4968 KB;
Shaping rate: 3192 Kbps.
 
Downstream: Burst size: 9765-10006 KB;
Shaping rate: 17061 Kbps.
 

This is really a bummer given the higher cost and no promo offers for business lines. Personally I'm only paying the premium for no caps, 1being inline with the TOS, and better support. Based on the service I've been getting all around, I'm not sure it's worth the premium. The last problem I called about, it took them half a week to send a tech out.

muranternet

join:2009-10-19
Saint Paul, MN
Reviews:
·Comcast Business..

1 edit
reply to pflog

OK I seem to have my packet loss issues worked out (there were like 4 contributing factors) and got my SB6121 provisioned.

- location

St Paul, MN

- what modem do you have

SB6121

- original speed plan

12/2

- new speed plan

No notifications, but it looks like 15-16/3

- shaperprobe results

DiffProbe release. January 2012. Build 1008.
Shaper Detection Module.

Connected to server 38.102.0.87.

Estimating capacity:
Upstream: 11112 Kbps.
Downstream: 32957 Kbps.

The measurement will take upto 2.5 minutes. Please wait.

Checking for traffic shapers:

Upstream: Burst size: 4601-4892 KB;
Shaping rate: 3210 Kbps.

Downstream: Burst size: 9047-9978 KB;
Shaping rate: 16837 Kbps.

- do you see power boost? if so, is it more or less than before?

Powerboost is weird; I get inconsistent reported down (anywhere from 11-25) but ridiculous up.

»stage.results.speedtest.comcast.···4372.png

- do your speeds remain consistent after powerboost? or are they erratic as in the link

Seems stable at 2.0MB/s after boost on a 1.5GB test download.

***

Update: Techs reworked my line today because it was pretty old and grounded to a water pipe. Speedtests look normal now:

»stage.results.speedtest.comcast.···6662.png


hhahn

join:2011-06-25
Marlton, NJ

1 recommendation

reply to pflog

Did Comcast completely kill PowerBoost on the upload?

Ever since Comcast's support reset my modem, I'm not getting upload speeds any greater than my plan.

Here's what I have from my last test:




This is a test from before the new tiers. It's the most recent I was able to find.



It's pretty pathetic that Comcast had no problem rolling out new, much faster tiers for a wide variety of residential modems, yet they can't even get their config correct on a whopping three modems for business customers.


ropeguru
Premium
join:2001-01-25
Mechanicsville, VA

For me, yes, my upload powerboost is gone. I used to have download in the 70Mb range and upload was 10Mb. Now my PB iw 35/7.



csiemers

join:2000-09-16
Portland, OR
Reviews:
·Comcast
·VOIPO
reply to pflog

On my 12/2 here's what Sharperprobe says:
DiffProbe release. January 2012. Build 1008.
Shaper Detection Module.

Estimating capacity:
Upstream: 7044 Kbps.
Downstream: 33854 Kbps.

The measurement will take upto 2.5 minutes. Please wait.

Checking for traffic shapers:

Upstream: Burst size: 4389-4531 KB;
Shaping rate: 3136 Kbps.

Downstream: Burst size: 6214-7088 KB;
Shaping rate: 21989 Kbps.

And here's what SpeedTest says:




The SpeedTest values are the same ones I've been getting since I signed up for Comcast back in August of 2011.
--
»www.caryontech.com


pflog
Bueller? Bueller?
Premium,MVM
join:2001-09-01
El Dorado Hills, CA
kudos:3

Weird, you're getting 22/3 instead of 15/3. Enjoy that while it lasts and keep that modem on a UPS so it doesn't power cycle
--
"Women. Can't live with 'em, pass the beer nuts." -Norm



csiemers

join:2000-09-16
Portland, OR
Reviews:
·Comcast
·VOIPO

said by pflog:

Weird, you're getting 22/3 instead of 15/3. Enjoy that while it lasts and keep that modem on a UPS so it doesn't power cycle

It's been powered cycled many times and it's remained the same speed.
--
»www.caryontech.com


pflog
Bueller? Bueller?
Premium,MVM
join:2001-09-01
El Dorado Hills, CA
kudos:3

said by csiemers:

said by pflog:

Weird, you're getting 22/3 instead of 15/3. Enjoy that while it lasts and keep that modem on a UPS so it doesn't power cycle

It's been powered cycled many times and it's remained the same speed.

The point is, there is no 22/3 plan. So enjoy it while it lasts.
--
"Women. Can't live with 'em, pass the beer nuts." -Norm


pflog
Bueller? Bueller?
Premium,MVM
join:2001-09-01
El Dorado Hills, CA
kudos:3
reply to pflog

Click for full size
New boot files were released apparently. Is anyone seeing improved behavior of the speeds on 27/7 on SMC devices? I power cycled mine, but still getting the same erratic speeds after PB.

It does look like upstream PB is back, albeit less than before.

Powerboost results #1 (re-ran due to 'high packet loss' thing on download):

Estimating capacity:
Upstream: 14081 Kbps.
Downstream: 34882 Kbps.

Upstream: Burst size: 9717-9951 KB; Shaping rate: 7466 Kbps.
Downstream: Measurement aborted due to high packet loss rate.

Powerboost results #2:

Upstream: 13751 Kbps.
Downstream: 34769 Kbps.

Upstream: Burst size: 9574-9792 KB; Shaping rate: 7466 Kbps.
Downstream: Burst size: 18692-18878 KB; Shaping rate: 29008 Kbps.

Wireshark I/O graph attached (will re-attach, that previous one was the packets/s not bytes/s).


ropeguru
Premium
join:2001-01-25
Mechanicsville, VA

Click for full size
Click for full size
All of my stats are the same (ie. still no power boost). My graph isn't quite as bad as yours but does have som hiccups. I have power cycled the SMC multiple times too.

hhahn

join:2011-06-25
Marlton, NJ

I also still don't have Powerboost. I tried rebooting the modem today, but no change. It's completely gone on both the download and upload.

This sucks.



NetFixer
From my cold dead hands
Premium
join:2004-06-24
The Boro
Reviews:
·Cingular Wireless
·Comcast Business..
·Vonage
·Comcast

said by hhahn:

I also still don't have Powerboost. I tried rebooting the modem today, but no change. It's completely gone on both the download and upload.

This sucks.

I had to buy a managed switch so that I could limit the negative effects of Comcast's PowerBoost, and you get Comcast to do it for you for free.

This really sucks.
--
We can never have enough of nature.
We need to witness our own limits transgressed, and some life pasturing freely where we never wander.

hhahn

join:2011-06-25
Marlton, NJ

said by NetFixer:

said by hhahn:

I also still don't have Powerboost. I tried rebooting the modem today, but no change. It's completely gone on both the download and upload.

This sucks.

I had to buy a managed switch so that I could limit the negative effects of Comcast's PowerBoost, and you get Comcast to do it for you for free.

This really sucks.

Yeah, it really sucks when you're working over a VPN and every time you save, it takes 10-15 seconds to finish a save command.

Maybe if Comcast would simply offer halfway decent upload speeds, especially on their god damn business tiers, there wouldn't be as much of a demand.


ropeguru
Premium
join:2001-01-25
Mechanicsville, VA
reply to pflog

Looks like they have really fubar'ed something in the config now. When I run a shaper probe it is intermittently failing on too much packet loss. Pinging from the inside out I see the loss and when pinging from the outside to the default gateway IP on the SMC, it also starts throwing timeouts, which tells me the SMC is having issues.

Update: Even when pinging the WAN DHCP IP address on the SMC, it also starts timing out along with the other IP's. So this is definitely a SMC issue all around not just a router processing issue within the SMC.



pflog
Bueller? Bueller?
Premium,MVM
join:2001-09-01
El Dorado Hills, CA
kudos:3

1 edit

Click for full size
Looks like unfortunately the Netgear device doesn't help with this 27/7 issue. Although the speeds are more sawtooth and less erratic now with the Netgear, there's clearly still an issue with the speeds after power boost ends.

However, the tech said something about pulling the boot file and config from my SMC and then pushing one or both to the Netgear, so perhaps he wasn't supposed to do that, not sure.

On the plus side, my SNR was sitting between 35 and 35.5 on the 4 channels on the SMC, and this Netgear's 8 channels are sitting at 37+, so I can't complain about that.

*edit* Adding shaperprobe results:

Estimating capacity:
Upstream: 10800 Kbps.
Downstream: 35398 Kbps.

Upstream: Burst size: 9795-9915 KB; Shaping rate: 7429 Kbps.

Downstream: Burst size: 20208-20442 KB; Shaping rate: 28560 Kbps.

The tech brought up a good point. Powerboost fluctuates based on the load in the CMTS right? Could it be as simple as my CMTS thinking "powerboost is still uncapped" but the boot file is capping it? If the CMTS is "leaving the flood gates open", but the modem is clamping it, couldn't it cause exactly this behavior (packet loss, which causes the TCP stack to back off, then ramp back up, etc etc)?


espaeth
Digital Plumber
Premium,MVM
join:2001-04-21
Minneapolis, MN
kudos:2
Reviews:
·Vitelity VOIP

1 recommendation

said by pflog:

The tech brought up a good point. Powerboost fluctuates based on the load in the CMTS right? Could it be as simple as my CMTS thinking "powerboost is still uncapped" but the boot file is capping it? If the CMTS is "leaving the flood gates open", but the modem is clamping it, couldn't it cause exactly this behavior (packet loss, which causes the TCP stack to back off, then ramp back up, etc etc)?

Not really. This is a rate shaping vs rate limiting problem. TCP automatically rate limits itself in relation to RTT and packet loss.

Rate shaping is about exploiting that function of TCP and implementing a "leaky bucket" mechanism where you start discarding packets even before the rate threshold is crossed. This causes TCP to back off on how quickly it tries to scale the ACK window and when you zoom out a bit on the IO graph you get that relatively smooth line you're accustomed to seeing.

Rate limiting is generally implemented as a strict threshold limit. All packets under the "bucket" threshold are accepted, everything above the threshold is dropped. This creates problems for TCP because each time it scales the window it sees 0 drops while still under the threshold which causes it to continue to be aggressive with the scaling. Eventually it scales pass the threshold, loses more than a few % of a congestion window's worth of packets, and kicks in congestion avoidance by cutting the TCP window to 1/2 of what it was. That process results in the sawtooth graph you see above.

Given that you're seeing the same behavior with 2 different CPE devices, I would speculate they are probably implementing the downstream shaping on the CMTS (this is logically the best place to do it anyway). I suspect either the CMTS profile for the 27/7 offering is incorrect, or the configuration may have found a code bug that causes rate shaping to not operate correctly with these specific parameters used.


pflog
Bueller? Bueller?
Premium,MVM
join:2001-09-01
El Dorado Hills, CA
kudos:3

Yeah it seems pretty clear that the CMTS and 27/7 profiles are not playing nicely together in some areas, while they're ok in others.

I'm not even sure who needs to address this at this point? It seems like a localized issue that the CMTS engineers would need to fix/update, but how we get their attention is unknown to me.

ComcastDJ See Profile and jlivingood See Profile were/are both looking into this, but they were hoping the new Netgear modem would fix it. I'm not sure if they have the means or "authority" to push for CMTS updates in various places or if that all has to be driven locally.
--
"Women. Can't live with 'em, pass the beer nuts." -Norm



ropeguru
Premium
join:2001-01-25
Mechanicsville, VA

Off topic, but does the Netgear allow for native IPv6? If so, are you seeing it available at your location?