Pls HELP Guys!! 1

[talkdev]

Hi i have a simple conceptual problem i want to know the basic design part of a leased line through cable.Suppose in my company a leased line of 128 kbps is coming from our isp through cable and ending at modem and from modem to router.Now i want to know what kind of setup would be at ISP end i mean is the cable coming directly from a router or switch ??
Pls help me to understand this
thanx in advance for ur kind support

 

[ChrisAC]

On either end of the leased line you have an NTE/NTU (Network Termination Equipment/Unit). On the remote end this will most likely have a single port for an X.21 cable or G.703. We now only use X.21. On the core end (the ISP) it will be a similar setup but the NTE/NTU will have many ports. Ours patch into a router via an X.21 cable then into a serial port on an 8 port card although the latest card has a single port with a spider cable attached which connects into 8 NTE ports. Our telco guys build the circuit from NTE to NTE and test it. They then assign it a port on the router which the IP guys configure for that circuit.

The only difference is how it's presented is whether it's a full 2MB port or a bearer service. If the customer has a 64K, 128K or 256K connection then the line terminates on a bearer and the circuit is allocated a number of 64K channels. So, if they want a 128K leased line then they'll get two "timeslots" on that bearer. Each bearer has 32 channels that makes up a 2MB connection to a core router.

If the line is 512K, 1MB or 2MB then the customer gets a full 2MB port on the router and that port can be rate limited to match the speed that they have paid for.

I hope that this helps.

Chris.
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Chris Andrew, CCNA
chris@iproute.co.uk
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[talkdev]

thanx chris you are my hero .One more time i want to give u trouble , i just want some good sites on the net which can provide lots of things about these types of technlogies and do we use Multiplexer also in this "time slot" thing?
bye bye and thanx again..
dev

 

[ChrisAC]

As far as web sites go, I haven't really been able to find any good ones. If I do then you'll be the first to know.

With regard to multiplexers, yes, we do use lots of them. When your signal goes to the local exchange, it's multiplexed in to a fibre connection that carries it off to the telco. Once there the signal is de-multiplexed and fed off to the correct piece of equipment, in our case the other NTE. The "timeslots" on the bearer are like virtual circuits on a 2MB port. Each 2MB port carries a number of 64K channels which are multiplexed into a 2MB circuit.

Chris.
************************
Chris Andrew, CCNA
chris@iproute.co.uk
************************

 

[talkdev]

Hey Chris thank you very much ! now i got hold of things and realy men u r the one..I dont have words to convey that how much u helped me..Anyways thanx again and will get back to u in case of any new problem... bye bye and take care
thanx again
dev
talk_dev@hotmail.com