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What is framing and linecode in ISDN?

What is "router2(config)# controller t1 0/0" -> "router2(config-controller)# framing esf" -> "router2(config-controller)# linecode b8zs" -> "router2(config-controller)# pri-group timeslots 1-24" ? Can someone explain what does each command mean? What is framing and linecode? How many are they?


Re: What is framing and linecode in ISDN?

The Controller of a router is the physical interface to the router for the T-1. IT is an internal CSU/DSU that you need to configure further. The Framing ESF is the framing for the T-1. It needs to match what the carrier is providing to you on the T-1 line. ESF is called Extended SuperFrame. It provides for enhanced signaling and inband capabilities that D4(Superframe) cannot. It also allows for Nx64 bandwidth timeslots. D4 only allows for Nx56k. It is predominantly the framing used for most T-1's today unless you are using the T-1 for voice specifically and then you do not need the Nx56k bandwidth... The Linecode B8ZS is the coding for the T-1. It allows for a strict timing envelope . If your data exceeds more then 8 bits the timing/clocking of the T-1 can slip and cause bit errors and frame errors. By enabling B8ZS (Alos must be matched with the carrier) you ensure that you will not get timing errors or slips from any excess zeros sent on the line...The Pri group sets up your Controller for internal CSU/DSU functions. You can map specific DS0's of the T-1 to certain Pri-groups. The PRI-group is specifically used for ISDN PRI lines where you are setting the ISDN lines with certain timeslots of the T-1. In this case all 24 timeslots of the T-1 are being mapped to the ISDN PRI group for 1536k total bandwidth... Hope I answered your questions.. Good Luck... Please rate...Thanks...

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