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brycenesbitt

join:2000-10-27
Berkeley, CA

Why the VRAD (technical question)

They're sprouting like mushrooms. Near every traditional green AT&T interconnection box sprouts a 2nd nearby box with a VRAD. The VRAD box is sometimes across the street, but always nearby.

Apparently there's a cross connect cable to the VRAD. When someone signs up they find the wire in the old box, and wire it over to VRAD. If the customer discontinues U-Verse and switches to a competitive ISP, the cross connect wire is removed.

The question is why? Why can't AT&T design a new version of the switch box that terminates all incoming (from CO) wires, and outgoing (to homes) onto electronic switches. Now a flip of a switch could enable U-Verse (and disable competitive ISPs). It just seems like the wiring would be so much easier... what am I missing?

One box, electronic switching, easy expansion.



NormanS
I gave her time to steal my mind away
Premium,MVM
join:2001-02-14
San Jose, CA
kudos:11
Reviews:
·SONIC.NET
·Pacific Bell - SBC

Short answer: AT&T doesn't want my business, so I won't give it to them. If I couldn't get Sonic.net "Fusion" out of the local CO, I'd get Comcast instead. No financial incentive for AT&T, since they are too cheap to deploy FTTP.
--
Norman
~Oh Lord, why have you come
~To Konnyu, with the Lion and the Drum



rolande
Certifiable
Premium,Mod
join:2002-05-24
Dallas, TX
kudos:5
Reviews:
·AT&T U-Verse
·ViaTalk
reply to brycenesbitt

The separation of the physical cabling infrastructure and the services infrastructure, I believe, is based on regulatory requirements and the separation of the actual business units themselves inside AT&T/SBC etc. There are definitely legal separation issues at play that create this arrangement. It is not a pure technical design choice. It is a political business environment that forces this design choice.
--
Scott, CCIE #14618 Routing & Switching
»rolande.wordpress.com/


HeadSpinning
MNSi Internet

join:2005-05-29
Windsor, ON
kudos:5
reply to brycenesbitt

said by brycenesbitt:

They're sprouting like mushrooms. Near every traditional green AT&T interconnection box sprouts a 2nd nearby box with a VRAD. The VRAD box is sometimes across the street, but always nearby.

Apparently there's a cross connect cable to the VRAD. When someone signs up they find the wire in the old box, and wire it over to VRAD. If the customer discontinues U-Verse and switches to a competitive ISP, the cross connect wire is removed.

The question is why? Why can't AT&T design a new version of the switch box that terminates all incoming (from CO) wires, and outgoing (to homes) onto electronic switches. Now a flip of a switch could enable U-Verse (and disable competitive ISPs). It just seems like the wiring would be so much easier... what am I missing?

One box, electronic switching, easy expansion.

If their deployment is anything like what Bell Canada's FTTN deployment up here is, then the VRAD boxes ONLY contain a DSLAM - no dialtone originating equipment.

Since the dialtone originates from either the main Central Office (CO) or a remote (either a small building, or a concrete pad mounted Subscriber Line Carrier or SLC), it has to be wired over to the VRAD to add the DSL signal, then back to go to the subscriber.

The junction point for the CO/SLC wiring and the distribution wiring is at the "green box", everything must still pass through there. There isn't enough room to mount the VRAD inside these boxes, so it must be located nearby wherever they can get municipal consent to install it. They then connect it back to the "green box" with multi pair feeder cable.

When a customer signs up for U-Verse, AT&T sends a technician out to the green box to "detour" the customer's dialtone through the VRAD and back. Since not all customers sign up for U-Verse, it doesn't make sense to expend the capital to run everyone's line through the VRAD - just those that subscribe.
--
MNSi Internet - »www.mnsi.net


ArgMeMatey

join:2001-08-09
Milwaukee, WI
kudos:2
Reviews:
·voip.ms
·AT&T Midwest
·Time Warner Cable
reply to brycenesbitt

When I switched from AT&T ADSL to AT&T UVerse VDSL in 2011, there was virtually no interruption in POTS, the same line upon which both my ADSL and VDSL rode.

That is, I was there when the DSL went dead, and the UVerse had sync almost immediately - certainly less time than it would have taken to swing a XC at the crossbox. In fact I looked down the street and never saw anybody at the crossbox/VRAD. As far as I could tell, there was no interruption in POTS on the day of the change.

My guess was that they had wired my POTS/DSL line through the VRAD long before, maybe before I'd ordered, and on the day of the change simply turned off the DSLAM port or disconnected the XC from the POTS splitter at the wire center, and turned on the VRAD port. Other theories welcome.
--
USNG:
16TDN2870
Find your USNG coordinates:
USNGWeb


HeadSpinning
MNSi Internet

join:2005-05-29
Windsor, ON
kudos:5

said by ArgMeMatey:

Other theories welcome.

You could have been moved to the VRAD previously, but simply been on a regular DSL speed profile.

Most certainly, you would have required a modem change at your house.

Most modern VDSL DSLAMs will sync in both ADSL and VDSL mode.
--
MNSi Internet - »www.mnsi.net

TBBroadband

join:2012-10-26
Fremont, OH
reply to brycenesbitt

Competitive ISPs are only aDSL for the most part. It is rare that any ISP has the U-Verse network so it doesn't make sense to disconnect and move.



NormanS
I gave her time to steal my mind away
Premium,MVM
join:2001-02-14
San Jose, CA
kudos:11
Reviews:
·SONIC.NET
·Pacific Bell - SBC

Just to point out that CLECs offering resold AT&T do so from AT&T equipment, unless they have their own DSLAMs in the COs. Also, AT&T does not wholesale U-verse at all, so CLEC service could never come through a VRAD.
--
Norman
~Oh Lord, why have you come
~To Konnyu, with the Lion and the Drum


TBBroadband

join:2012-10-26
Fremont, OH

Actually Norman there are a few ISPs that have been granted this option. Please check your PMs regarding this as per DSLR rules I can not mention much on AT&T's thread due to "advertising" issues.



ArgMeMatey

join:2001-08-09
Milwaukee, WI
kudos:2
Reviews:
·voip.ms
·AT&T Midwest
·Time Warner Cable
reply to HeadSpinning

said by HeadSpinning:

You could have been moved to the VRAD previously, but simply been on a regular DSL speed profile.

Most certainly, you would have required a modem change at your house.

Based on the Speedstream log, there was no change in the equipment to which it was connected prior to it going dead, at least up until about a half hour before it went dead.

There was no modem change at my house until I unplugged the Speedstream 4100 and plugged in the 2Wire 3600HGV.
--
USNG:
16TDN2870
Find your USNG coordinates:
USNGWeb

HeadSpinning
MNSi Internet

join:2005-05-29
Windsor, ON
kudos:5

The telco side equipment either had to have been changed at some point, or you were on a VRAD for a while and just didn't know it. Regardless, at some point, your connection had to have been transferred to the VRAD.
--
MNSi Internet - »www.mnsi.net



OSUGoose

join:2007-12-27
Columbus, OH
reply to brycenesbitt

The question then becomes, at the RT's why not integrate the VRAD hardware in them. Most are fiber fed from the CO already, and are used as DSLAMs. Surely upgrading the hardware inside would free up space, and reduce AT&T's footprint (thus not pissing off as many neighbors).

What feed me right now is a RT, and yet there is a old lightspan SLC (in puke brown and crème) next to it. Why not upgrade the gear in the RT, and splice in the cabling in the SLC into the RT and eliminate that SLC. I've been told that all that would be needed to add u-verse to my address is the hardware be put into the RT or next to it.



weaseled386

join:2008-04-13
Edgewater, FL
Reviews:
·Bright House
·AT&T U-Verse

1 edit

said by OSUGoose:

The question then becomes, at the RT's why not integrate the VRAD hardware in them. Most are fiber fed from the CO already, and are used as DSLAMs. Surely upgrading the hardware inside would free up space, and reduce AT&T's footprint (thus not pissing off as many neighbors).

What feed me right now is a RT, and yet there is a old lightspan SLC (in puke brown and crème) next to it. Why not upgrade the gear in the RT, and splice in the cabling in the SLC into the RT and eliminate that SLC. I've been told that all that would be needed to add u-verse to my address is the hardware be put into the RT or next to it.

I install, upgrade, remove, maintain AT&T's RT sites for a living. The 7330's cannot be installed in the 80-type cabinets for MANY reasons. Here are a few:

1) Power: The legacy power systems are limited to 10A per load. Most of them are maxed with a combo of SLC channel banks, multiplexers and T1 repeater shelves. Each Alcatel 7330 (VRAD) needs two 20A feeds.

2) Battery backup: The cabinets lack space for adequate sized batteries.

3) Protectors: Every circuit in the cabinet must have surge suppression. The 80-cabinets can only handle ten 307C protectors.

4) Clearance: The doors on the cabinet would hit the front of the shelf, and prevent the doors from closing.

EDIT: sorry, I didn't catch an important part of your question -- that the 80 cabinet is sitting outside of an existing RT. Can you post a pic? I'd need to know what type of RT it is sitting next to before I could make any sort of guess.


OSUGoose

join:2007-12-27
Columbus, OH

It's not, that is simply what AT&T techs say is all that would be needed or to add the hardware in the RT.



weaseled386

join:2008-04-13
Edgewater, FL
Reviews:
·Bright House
·AT&T U-Verse

said by OSUGoose:

It's not, that is simply what AT&T techs say is all that would be needed or to add the hardware in the RT.

There is a reason AT&T doesn't install their own equipment... Without knowing more I guess you'll have to be happy knowing that the 7330 simply will not physically fit in the 80A, 80C, 80D or 80E distributed power cabinets.


OSUGoose

join:2007-12-27
Columbus, OH

lol, should the fact that they had someone out here in April or May "pair conditioning" for u-verse mean anything. I know the cable path and have been told they will need to run fiber deeper down the road and create a SAI to splice into. As there is no crossconnect/SAI between here and the RT.



weaseled386

join:2008-04-13
Edgewater, FL
Reviews:
·Bright House
·AT&T U-Verse

said by OSUGoose:

lol, should the fact that they had someone out here in April or May "pair conditioning" for u-verse mean anything. I know the cable path and have been told they will need to run fiber deeper down the road and create a SAI to splice into. As there is no crossconnect/SAI between here and the RT.

The reason the 7330's are typically placed near cross-boxes (vs inside RT's) is because the xboxes are typically fed from 2+ RT's. The older DSL didn't work the same way...

On older ADSL you had tie pair blocks with IN and OUT. The POTS line would wire wrap to the IN side which would send it into the DSLAM. Then the OUT side would go to the customer with ADSL riding the pair.

So, essentially, God only knows what they're doing at this point.

brycenesbitt

join:2000-10-27
Berkeley, CA
reply to weaseled386

It would help to have a definition of some terms. RT? 7330? VRAD? Type 80?

--------------------------------------------------------
Surely AT&T could design a modern dropin for the old style cross-connect box. It would terminate all the incoming wires, and all the outgoing ones onto circuit boards.

A customer on POTS or a competitive ISP would be digitally switched from in to out. Nothing would change from the point of view of the customer equipment or the central office.

A customer on U-Verse would be digitally connected to a vdsl port within the same cabinet. Surely at least, say, ten vrad ports would fit. Maybe more, but clearly there is some room in those cabinets.

Only when the 11th customer signs up for U-Verse then AT&T needs to build a nearby box to house the extra equipment and power supply. The cable between the two can be a single fiber.
--------------------------------------------------------

Is there a flaw in this thinking? Is AT&T installing more cabinets than really needed? If AT&T did it, would the regulations then open them up to giving access to competitive ISPs?



NormanS
I gave her time to steal my mind away
Premium,MVM
join:2001-02-14
San Jose, CA
kudos:11
Reviews:
·SONIC.NET
·Pacific Bell - SBC

said by brycenesbitt:

It would help to have a definition of some terms. RT? 7330? VRAD? Type 80?

RT=Remote Terminal. A powered box housing switchgear and a DSLAM; a mini-CO, if you will. May be fiber fed, or T1 fed.
VRAD=Video Ready Access Device. A powered box containing a Video DSLAM. Fiber fed.
7330, Type 80, etc.=The "guts" of those boxes.

Surely AT&T could design a modern dropin for the old style cross-connect box. It would terminate all the incoming wires, and all the outgoing ones onto circuit boards.

Ever compare the external dimensions of the SAI (Serving Area Interface; aka, "cross-connect") with the external dimensions of an RT, or VRAD? The interior of the SAI cabinet is a bit tight for the electronics necessary to feed every residence served out of the SAI box.

Is there a flaw in this thinking? Is AT&T installing more cabinets than really needed? If AT&T did it, would the regulations then open them up to giving access to competitive ISPs?

Yes.
No.
The regulations are irrelevant, in that "Regulatory Capture" renders the concern moot.
--
Norman
~Oh Lord, why have you come
~To Konnyu, with the Lion and the Drum

brycenesbitt

join:2000-10-27
Berkeley, CA

said by NormanS:

Ever compare the external dimensions of the SAI (Serving Area Interface; aka, "cross-connect") with the external dimensions of an RT, or VRAD? The interior of the SAI cabinet is a bit tight for the electronics necessary to feed every residence served out of the SAI box.

The VRAD used in our area is about the same dimension, but perhaps 50% thicker, than the nearby SAI.

In many areas here a 50% thicker box could be set on the same pad as the old SAI and would "fit". Thus a VRAD size box could sit on a SAI pad.

And beside: every year electronics get smaller. The old SAI uses giant connectors for the incoming terminations, for example, which could be terminated onto much smaller junction blocks.


rolande
Certifiable
Premium,Mod
join:2002-05-24
Dallas, TX
kudos:5
Reviews:
·AT&T U-Verse
·ViaTalk
reply to brycenesbitt

The U-verse VRAD (Video Ready Access Device) uses an Alcatel 7330 chassis to deliver VDSL services from modular cards. That network component, required to deliver U-verse services, does not physically fit in the design of the existing RTs (Remote Terminal) and requires a different power design than the current RTs are equipped with. It is a simple problem of a square peg not fitting in a round hole. Eventually the old RTs will get decommissioned, as all customer service offerings move off of the old platform.
--
Scott, CCIE #14618 Routing & Switching
»rolande.wordpress.com/



ILpt4U
Premium
join:2006-11-12
Lisle, IL
kudos:9

There are 7330s in previously existing RTs/CEVs out there... may not be a lot, but they do exist


brycenesbitt

join:2000-10-27
Berkeley, CA
reply to brycenesbitt

Ok, the new stuff won't fit in the old cabinet.

But what if you airlift that cabinet out of there, and place a new cabinet and new power feed at the same location.
Terminate all wires.
Either run POTS as an electronic switch in and out, or put termination equipment there.
Of course you'd put DSL equipment in also.
How much bigger would THAT need to be?

Or, better yet. Airlift the old box out. Put nothing in the cabinet but the front end of the dslam. Run the actual dslam
via fiber from the CO (e.g. a remote processing unit). Install dedicated fiber since there will be a lot of bandwidth.