Cisco ASR 9000 Series User Manual

Prerequisites for Implementing PTP on Cisco IOS XR Software
You must be in a user group associated with a task group that includes the proper task IDs. The command
reference guides include the task IDs required for each command. If you suspect user group assignment is
preventing you from using a command, contact your AAA administrator for assistance.
Information About Configuring PTP
PTP Implementation
IEEE Standard 1588-2008 defines a method for distributing time around a network using the Precision Time
Protocol (PTP) version 2. PTP ensures that the best available clock is selected as the source of time (the
grandmaster clock) for the network and that other clocks in the network are synchronized to the grandmaster.
PTP consists of two parts:
•
The port state machine and best master clock algorithm, which provides a method to determine which
ports in the network will run as master (providing time to other clocks to the network), which will run
as slaves (receiving time from other clocks in the network), and which will be passive (neither master
nor slave).
•
Mechanisms for slave ports to calculate the difference between the time of their own clocks and the time
of their master clock. To calculate the differences, PTP uses a delay request/response mechanism and a
peer delay mechanism.
Peer-delay mechanism is not supported on the Cisco ASR 9000 Series routers.Note
The implementation of PTP on Cisco IOS XR software is designed to operate effectively in Telecommunication
networks, which are different from the networks for which PTP was originally designed.
PTP is configurable on Gigabit Ethernet interfaces (G, 10G, 40G, and 100G), Bundle Ethernet interfaces, and
sub-interfaces. PTP is not configurable on LAG Ethernet sub-interfaces.
PTP Transport Media
PTP is supported over the following transport media:
•
UDP over IPv4
PTP Messages
PTP supports the following message types:
•
Signaling
•
Announce
•
Sync
Cisco ASR 9000 Series Aggregation Services Router System Management Configuration Guide, Release 5.1.x
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Configuring PTP
Prerequisites for Implementing PTP on Cisco IOS XR Software

Cisco ASR 9000 Series Specifications

General

Brand	Cisco
Model	ASR 9000 Series
Category	Network Router
Language	English