After a few off-list responses (and a couple on) encouraging me to use NANOG, here we go...

I've recently walked in to a voice\DSL CLEC that has basically been left to entropy for the last ten years. A lot of the core systems just work, but a lot of things aren't exactly managed the best. They run a Calix\Occam ADSL2+\VDSL infrastructure. For those of you doing DSL, what CPE are you using? I'm looking at one that's just a basic modem where I have a more sophisticated router (or ATA\voice gateway) behind it and then one more generic for residential settings with WiFi and all that jazz. We're kinda debating whether we go just dumb Wi-Fi or something more advanced\powerful. I've heard a lot of good about the Calix GigaFamily in that regard.

The CLEC that I do some contract work for uses a basic single port ethernet
only Comtrend 5072T ADSL2+ modem for all residential customers and business
customers who don't have a bonded connection. Very reliable modem. The 5071
had bad powersupplies, but seemed worked better on loops with lousy stats.
I think their idea is less tech support calls when a customer complains
that they cannot connect a wifi device or doesn't know what the password
is. Less things to break or have to maintain. The CLEC tells the customer
to buy their own wireless router which 95% of the customers already have or
have no issues in buying. For the business customers who have a bonded
ADSL2+ connection, they use a Zyxel VMG4325 modem/router/wifi CPE device.
It has a lot of configuration options. I'm not sure how reliable they are.
I've been on a few trouble calls where I had to replace a questionable
modem or the modem didn't like when one of the two bonded loops had issues
(modem wouldn't pass upstream traffic instead of just knocking out the bad
loop). The CLEC doesn't use PPPoE at all.

The LEC in this state (Fairpoint) uses similar hardware. I think Fairpoint
has a Comtrend provisioning box to push out the PPPoE settings for Comtrend
modems which is really handy for them.

Hope this helps in some limited way.


Joshua Zukerman
Snow Pond Technology Group Inc.

We're using Visionnet m505+. They seem to do well enough for our users. Our DSL footprint more rural than not and a few have needed range extenders for larger houses as these only have N wireless. I can get pretty much any stats I need from them by logging in and poking around the statistics pages except for how often the modem is resynchronizing with our Calix. I can get that stat from the Calix shelf though or make a rough guess based on an internal tool we made. I have no complaints with the modem.

If you get a lot of calls from people with security cameras that use internal/external IPs and port forwarding you may have some trouble, I haven't been able to figure out how to make it do a hairpin gracefully.

At $dayjob we use both Comtrend and Zyxel modems. Both have a 1-port modem that can be deployed in bridged mode. They both seem to work well with Calix gear. We've found the Zyxel modems tend to work a little better at longer loop lengths. But, for us at least, it's very easy to get custom firmware created and pre-deployed to comtrend modems at the factory / distributor. So we haven't completely decided between one brand and the other. We started looking at Zyxel for increased speed at longer loop lengths and better wifi support.

There's a company a few exchanges over from us that has deployed the caix giga family and really likes it. We haven't deployed them yet because they only work on the Calix E7 series (E7-2 and E7-20) and we still have a lot of C7 series dslams in the network.


Any particular Zyxel models or just Zyxel in general perform better at longer lengths?


You want to look at what Broadcom chipsets are in this DSL CPEs. Broadcom
is the king and leader in the DSL space.

We used the Comtrend 3120 as it has one of the latest Broadcom chipsets on
the market. I know you love to check FCC ID's so this should be helpful for
you: https://wikidevi.com/wiki/Broadcom#xDSL

The Comtrend 3120 uses the BCM63138. Dual core 1Ghz. It makes a difference
even if the mode is in pure bridge mode. There aren't many bonded modems
that don't have wifi built in as the chipset includes wifi.

Sorry -- this got lost in the shuffle.

We were specifically comparing Comtrend AR5381u vs Zyxel 660HN being fed with either Calix ADSL 2+ or Paradyne/Zhone Bitstorm ADSL2+. All use the broadcom chipset but seem to interop slightly differently. From our limited testing we determined that for the best speeds / quality on long loops order was like this

Zhone Bitstorm -> Zyxel 660HN
Zhone Bitstorm -> Comtrend AR5381u
Calix ADSL 2+ -> Zyxel 660HN
Calix ADSL 2+ -> Comtrend AR5381u