U K2 interface
With U K2 is the ISDN - Primary Rate Interface an interface for the transmission path between the local exchange (local exchange) of the network operator and the network termination ( NTPM ) designated by the customer. It requires two copper two -wire lines . The U in the designation stands for the reference point of the interface in the ISDN reference model (see figure), while the K for K is upferleitungen.
For physical transmission , the ternary HDB3 code is largely used in Germany , which is much more energy efficient than the AMI code used in the USA . For some years now, HDSL and SDSL have also been used increasingly around the world because of their greater range . The data transfer rate of the interface is a maximum of 2 Mbit / s.
literature
- Volker Jung, Hans-Jürgen Warnecke (Hrsg.): Handbook for telecommunications. Springer Verlag, Berlin / Heidelberg 1998, ISBN 978-3-642-97703-9 .
- Hubert Zitt: ISDN and DSL. Markt + Technik Verlag, Munich 2004, ISBN 3-8272-6630-0 .
- Andres Keller: Broadband cables and access networks. Technical principles and standards, Springer-Verlag, Berlin / Heidelberg 2011, ISBN 978-3-642-17631-9 .