Packet-over-SONET Interface Commands on the
Cisco ASR 9000 Series Router
This module provides command line interface (CLI) commands for configuring Packet-over-SONET/SDH
(POS) on the Cisco ASR 9000 Series Router.
This module describes the Cisco IOS XR commands used to configure, monitor, and troubleshoot
Packet-over-SONET/SDH (POS).
POS provides a method for efficiently carrying data packets in SONET or Synchronous Digital Hierarchy
(SDH) frames. High-bandwidth capacity and efficient link utilization are characteristics that make POS
largely preferred for building the core of data networks. POS uses PPP in High-Level Data Link Control
(HDLC)-like framing for data encapsulation at Layer 2 (data link) of the Open System Interconnection (OSI)
stack. This method provides efficient packet delineation and error control.
In addition to high-bandwidth efficiency, POS offers secure and reliable transmission for data. Reliable data
transfer depends on timing integrity.
The real-time POS functionality is performed in hardware, according to the hardware configuration setup.
Configured hardware events are detected by the framer application-specific integrated circuits (ASICs) and
the control is passed to the software. The generic POS driver is responsible for providing a mechanism to
configure the hardware on a per-interface basis, to handle interface state transitions, and to collect POS-related
statistics.
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Cisco ASR 9000 Series Aggregation Services Router Interface and Hardware Component Command Reference,
Release 5.3.x
693