Why does HDSL configuration use Frame-relay commands

[Minue]

Hello Guys
Below is a fully working HDSL configuration.I am now getting in to the HDSL world.But what's baffling me is why is the configuration exactly like a FRAME-RELAY connection.I thought it should be more like an ADSL or SDSL configuration.
Thanks in advance

interface Serial0/0
bandwidth 128000
no ip address
encapsulation frame-relay IETF
no ip route-cache
no ip mroute-cache
no fair-queue
frame-relay traffic-shaping
frame-relay lmi-type ansi
!
interface Serial0/0.1 point-to-point
ip address xxx.xxx.xxx.164 255.255.255.192
no ip route-cache
no ip mroute-cache
no cdp enable
frame-relay interface-dlci xx

 

[jneiberger]

I doubt this is being handed off to you as HDSL. HDSL is often the transport for T1 services in newer areas because it only requires one pair of wires and it causes less interference with other services (compared to two-pair T1). There is a device at the demarc that converts the signal from HDSL to two-pair T1 signaling that you're used to seeing.

So, long story short, this is simply a frame relay T1 from your perspective, not an HDSL circuit.

That's just my opinion based on the information you've given, though. I may be completely wrong.

 

[plshlpme]

what other equipment do you have on site from the telco?
HDSL will have a pairgain device to terminate the HDSL portion and then a csu or some sort..

now alot of providers are putting frame-relay onto point to point t1s just for the traffic shaping capabilities for fractional services..

do you have a paradyne or some sort of frame-relay csu?

HDSL will not be terminated in your router. its very high voltage and the unit at your office will be powered by the CO.

 

[Minue]

Hello Guys
Thanks for the replies!
Plshlpme
I am not sure of the CSU because,it's a config that someone in my Country posted as an HDSL connection.I also once sold a Router to a small company and they ask me to help them out with a config for a HDSL 2MB line that they bought.Didn't knew anything about HDSL configuration,so I google the Web in Italian.Found a similar config to the one I posted.I give it to the company,(What a sweat!!!)Suprisingly they call back and told me it was working perfectly.
I really don't know if we do things different here in Italy,but the providers sell those lines as HDSL.I know that the router use the WIC-1T and the DTE-DB60 V35 cable to connect to some CSU.But can't figure out why the config is Frame-relay.
Have any of you done a HDSL configuration?I would like to see one if have.
Regards

 

[burtsbees]

As plshlpme put it...
"now alot of providers are putting frame-relay onto point to point t1s just for the traffic shaping capabilities for fractional services.."
If your serial connection goes to a csu/dsu, then a frame configuration will indeed work. The csu/dsu perhaps is the demarc, and it is what goes to a DSLAM.

Burt

 

[jneiberger]

If your serial connection goes to a csu/dsu, then a frame configuration will indeed work."

That's not true, actually. The CSU/DSU is an interface between the serial interface on the router and the T1 (in this case) facilities on the circuit. It has nothing to do with whether or not the circuit uses frame relay. The frame relay configuration works in this case because the circuit terminates on a frame relay switch (or a device acting as one) at the central office.

Remember, frame relay is a layer two protocol, while a CSU/DSU is simply a layer one device.

 

[Minue]

Hello Guys
Call me mad!!Or maybe the Italian providers are using the word "HDSL" in the wrong sense.But here's a link in Italian for a HDSL configuration.

http://www.debug.it/pub/it/home/CiscoFaq/faq6.html

Regards

 

[plshlpme]

well we use hdsl all the time..
hdsl2 only needs one pair to deliver the t1 and it works really well.
so like jneiberger said.. think of the hdsl as layer 1.
the layer2 and layer3 config of your router will be provider specific..
we use hdsl all the time and with our customers and they work well..

some examples..
customer has a central hub location and many spokes..
well we can use the hdsl to deliver the t1 facility to the spokes.. and then into a passport with a fratm interface to convert the frame-relay to atm. that way the customer can have t1 speeds to its spokes and and atm interface at the hub site (ds3, oc3 etc)

in other cases customers order a point to point t1.. we will run hdsl as well but it terminates on the pairgain.

from a testers point of view hdsl is great as well.. it draws you a picture of the local unit and the co unit and shows which spans the errors are coming in on.. it is also a great way to prove power outages at customer locations since the remote unit is powered by the CO..
so if you can access the remote unit and see a LOSS coming from their router you know with pretty good certainty that there is a power problem at the site.

 

[Minue]

Hello plshlpme
Thanks for the the explanation.But this concept is way out my league.Next week I will start a new job with an ISP,so once I am in,I will get a clearer idea of the concept.I was trying to brush up before I start the job,so that I could make a good impression.But I guess they will accept the fact that I am only a CCNA with little experience.
Regard