CenturyLink VDSL2 + Transparent Bridging == Slower?

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svet-am

Supreme [H]ardness
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I recently had some accounting and trustworthiness issues with Comcast, so I dropped them and went with CenturyLink for VDSL2 here in Denver.

I spoke with the tech who hooked up my connection. I am literally across the street from my local node (I can see it next to my neighbors house across the street). I ran a dedicated line from the NID to my network room via CAT5e and I purchased an Actiontec C1000a.

Immediately after getting the service turned out, I did some speedtests and nearly maxed out the data rate I'm paying for (~38down / ~4.5up and I'm on a 40/5 plan).

I then switched my Actiontec modem into transparent bridging mode so that I can let my DD-WRT router handle things and now the max I can get down is ~19.5Mbps. I still get ~4Mbps up.

Is this a known "shortcoming" of transparent bridging mode? Is there something I can do about it from the DD-WRT side?
 
Are you plugged in physically or are you over wireless?

I never test faster than 20 Mbps or so on my 100mb line over wireless n. Get 102 when physically cables in.
 
Soldier101 said:
Are you plugged in physically or are you over wireless?

I never test faster than 20 Mbps or so on my 100mb line over wireless n. Get 102 when physically cables in.
Click to expand...

This is when connected via cable to my Gigabit network.
 
What hardware do you have dd-wrt running on? Have you ever tested more than 20Mbps through that hardware before?
 
I switched from Comcast to CenturyLink and had the same problem. Service was 20/1 but I only got 12/1 with transparent bridging through my pfSense router. The same router had no problem with 50/10 Comcast service.

Modem is an Actiontec Q1000A. I think your C1000A is the same model without wireless. In the end it didn't like the Broadcom NICs in the pfSense box. Switched to Intel NICs and it's 20/1 all day.
 
my router is a TP-LINK WDR4300 running DD-WRT v24-sp2-std. On Comcast, it was rock solid and I could *easily* do 50-55Mbps down and >15Mbps up. I know that it's not the router.

If something is "wrong", it's either on the DSL/CenturyLink side or there is a knob I need to turn in DD-WRT.
 
Swank said:
I switched from Comcast to CenturyLink and had the same problem. Service was 20/1 but I only got 12/1 with transparent bridging through my pfSense router. The same router had no problem with 50/10 Comcast service.

Modem is an Actiontec Q1000A. I think your C1000A is the same model without wireless. In the end it didn't like the Broadcom NICs in the pfSense box. Switched to Intel NICs and it's 20/1 all day.
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My C1000a has wireless too, but the antennas are internal. Here in the Denver metro, the C1000A is the *only* one I could get my hands on.
 
svet-am said:
my router is a TP-LINK WDR4300 running DD-WRT v24-sp2-std. On Comcast, it was rock solid and I could *easily* do 50-55Mbps down and >15Mbps up. I know that it's not the router.

If something is "wrong", it's either on the DSL/CenturyLink side or there is a knob I need to turn in DD-WRT.
Click to expand...

Most likely a knob you need to turn. If you are getting your speed with one and not the other, then the dsl link is fine.
 
I was poking around via the Googles this morning and came across the Motrola 2310-51. I even found one for sale on eBay, but it's model is 2310-51-1ATT, which I presume means it's an AT&T-branded model.

Does this work with CenturyLink?
 
It should be fine, might be something with DD-WRT. Does original firmware show the same performance?
//Danne
 
svet-am said:
I was poking around via the Googles this morning and came across the Motrola 2310-51. I even found one for sale on eBay, but it's model is 2310-51-1ATT, which I presume means it's an AT&T-branded model.

Does this work with CenturyLink?
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I wouldn't try it. We do use the 2310 for our pair bonded BiB customers, but they require provisioning before they will authenticate. If CenturyLink is rebranded att, you would probably run into a similar problem.
 
I have centurylink 40/5, I get full speed in bridge mode to pfsense firewall. Just ran this test:


Not sure if they have made an unofficial speed increase, but I setup the same 40/5 at a customer site last week, and I saw the modem was training at 50mb instead of around 40. I haven't logged into mine in months, so I'm not sure if mine is the same now.
 
I got home from work and my wife lit into me. She was supposed to work from home today but apparently the connection wqs dropping every hour - sometimes more than once per hour. She called technical support during the day and i phoned them this evening. they agreed that our situation sounds odd -- espescially given our proximity to the local node -- but their remote diagnostics show good SNR and all good connection metrics.

A tech is supposed to stop by during the day tomorrow to double check things in person. I have an ultimatum from the wife that if it is not fixed tomorrow then we're going back to comcast;
 
I'd revert firmware to original stock just to be safe, DD-WRT doesn't have the best track record...
//Danne
 
diizzy said:
I'd revert firmware to original stock just to be safe, DD-WRT doesn't have the best track record...
//Danne
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I'd like you to back that opinion up with some metrics.

I have literally spent *years* running DD-WRT on my routers with NO trouble whatsoever on cable Internet. It's going to be a VERY hard sell to convince me that DD-WRT is "the problem." Perhaps I could tweak something, yes, but not calling it the fundamental root of the issue. My honest opinion is that the Actiontec modem sucks and that behind the scenes Actiontec is pulling some tricks when it's in native mode that gets exposed when it is in bridged mode. As an engineer, science dictates that bridged mode *should be* faster in all cases since the modem has to do less work.
 
Fine, it flawless. If you're not even willing to debug what's the point of asking in the first place. As for DD-WRT just do a search here and you'll see what I mean.
//Danne
 
diizzy said:
Fine, it flawless. If you're not even willing to debug what's the point of asking in the first place. As for DD-WRT just do a search here and you'll see what I mean.
//Danne
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wow, I didn't say anything like that but way to go way out on a limb. I just asked you to back up your opinion with metrics and facts. I didn't say that my opinion was unmovable, just that it was going to take actual data to change it.
 
what happens if you plug a laptop into the bridged modem, pull a public DHCP IP and run a speed test? Eliminate the router completely.
 
Ehren8879 said:
what happens if you plug a laptop into the bridged modem, pull a public DHCP IP and run a speed test? Eliminate the router completely.
Click to expand...

How does this work with PPPOE? How do I have my PC log in?
 
I finally figured it out. It was a QoS policy issue. I had customized my QoS in DD-WRT when I was on Comcast and apparently that profile was no good for DSL. When I disabled QoS, speeds are what I expect.

So, that issue is solved....

Now, about the repeated disconnects. It is currently disconnecting ~4 times per day and is not automatically re-connecting successfully.

I called CenturyLink and basically got "Sorry, that just how DSL is.....and, don't forget to pay your bill on time!"
 
Again, that's weird, I have the same service and it's very reliable. I have nagios running on a server at home that connects up to multiple customer sites over vpn, running checks constantly (around 400 checks in every 5 minute period, so very constant). I see a centurylink outage about once every couple of months for maybe a minute or 2 (not counting a power outage in a storm or anything)
 
Ditto, my CenturyLink VDSL service has always been rock solid, way more reliable than Comcast. Suffer with the C1000a as your router for a while, see if the problem continues.
 
Revert the firmware as I said earlier, I may be the handling of the PPPoE protocol that's broken.
//Danne
 
diizzy said:
Revert the firmware as I said earlier, I may be the handling of the PPPoE protocol that's broken.
//Danne
Click to expand...

I actually decided to go one further and put the modem back into router mode and let it run over night. Sure enough, when I woke up the light was green but no data would go in or out. I had to power cycle to get it going again.

I have an ultimatum from my wife since she relies on the OwnCloud and SubSonic that we host to get it fixed soon (which in wife-speak is "today") or she's calling Comcast to go back.
 
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