Glossary
784 88000 Series
1588 PTP
Telecom Profile G.8265.1
The Telecom Profile G.8265.1 is designed for frequency synchronization in
Telecom network applications. The main attributes of this profile are:
Unicast communication with the Grand Master
UDP/IPv4 network layer
With the Telecom Profile, the Client Clock initiates the communication to
the Master Clock by making a request for service that consists of sending
Signaling messages containing a REQUEST UNICAST TRANSMISSION TLV
to the IP address of the Master Clock.
If the Master Clock has sufficient capacity to handle the Client Clock
request, it responds with a signaling message containing a GRANT
UNICAST TRANSMISSION TLV.
The REQUEST UNICAST TRANSMISSION TLV contains several parameters:
messageType is the type of service being requested: Announce,
Sync, or Delay Response.
durationField is the duration of the requested service:
300 seconds by default and configurable from 60 to 1000 seconds.
logInterMessagePeriod: transmission rate of the requested
messages.
If the Master Clock denies the request, e.g. because it has no remaining
capacity, it will send back a GRANT UNICAST TRANSMISSION TLV with the
durationField set to zero.
In the event of being denied service by a Master Clock, or receiving no
response to the service request, a Client Clock should wait a minimum of
one second before issuing a new Unicast request to that Master Clock.
As Unicast service is only granted for a limited time, the Client Clock must
re-request service periodically, before the expiration of the current grant.
The Client Clock should reissue the request sufficiently far in advance of
the expiration to allow the request to be repeated at least twice if no grant
is received. This parameter is called Unicast renewal interval.
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