WR changes for PTPv3: started writing profile

518beca9 · Maciej Lipinski · c630c0e5 · 518beca9 · 518beca9 · 518beca9
Commit 518beca9 authored Jan 24, 2013 by Maciej Lipinski
4 changed files
--- a/documents/WR_changes_for_PTPv3/changesToPtpv2.tex
+++ b/documents/WR_changes_for_PTPv3/changesToPtpv2.tex
 \section{Changes to PTPv2}
-\label{chap:changesToPtpv2}
\ No newline at end of file
+\label{chap:changesToPtpv2}
+
+
+\section{Transport Annex}
\ No newline at end of file
--- a/documents/WR_changes_for_PTPv3/highAccuracyOption.tex
+++ b/documents/WR_changes_for_PTPv3/highAccuracyOption.tex
@@ -25,7 +25,7 @@ not supporting PTP and/or High Accuracy options), the Signaling Messages defined
 clause shall be sent using the multicast address from the reserved (non-forwardable) 
 address space.

-\subsection{L1 Syntonization}
+\subsection{Layer 1 Syntonization}

 This option applies to clocks (PTP devices, i.e. OC, BC, TC) capable of transfering frequency
 over the physical layer (e.g. SyncE \cite{SynchE}). 
@@ -47,6 +47,9 @@ ingres frequency using \textit{L1 interface} (clause~\ref{chap:l1Interface}). On
 indicated that the device is frequency-locked, the L1\_SYNC\_LOCKED shall be sent to the 
 path-partner. 

+If no procedures by other options are required in the UNCALIBRATED state, the 
+MASTER\_CLOCK\_SELECTED event shall occure and SLAVE state shall be entered.
+
 \subsubsection{Frequency MASTER}

 A port of a frequency-transfer-enabled device that is in the MASTER state shall recognize
@@ -66,19 +69,33 @@ On \textit{timeout} an operation (i.e. sending Singaling Message) shall be repat
 by the SLAVE port (configurable Data Fields) and provided to the MASTER port using 
 L1\_SYNC\_SLAVE\_PRESENT Signaling Message.

+\subsubsection{SYNCHRONIZATION\_FAULT}
+
+Syntonization over Layer 1 provides increase in accuracy/precision of PTP-based 
+synchronization. It might happen that syntonization breaks (e.g. PLL looses lock) while
+PTP protocol maintains normal operation. In such case, the quality of synchronization
+might significantly deteriorate without means to detect such situation -- it can be 
+inacceptable with some applications. Therefore, a notification from H/W (i.e. PLL) shall be
+handled by devices implementing this clause. In particular, the H/W notification shall
+trigger SYNCHRONIZATION\_FAULT (clause~9.2.6.12 of \cite{PTPv2}). Consequently, SLAVE
+port enters UNCALIBRATED state in which the Layer 1 Syntonization is attempted to be 
+re-established. 
+

-\subsubsection{L1 Interface}
+\subsubsection{Layer 1 Interface}
 \label{chap:l1Interface}

 The interface to the hardware shall be defined in this clause, i.e.:
 \begin{itemize*}
-  \item frequency-lock request to H/W
-  \item frequency-lock-ready notification from H/W
-  \item frequency-source request to H/W
+  \item frequency-lock -- request to H/W
+  \item frequency-lock-ready -- notification from H/W
+  \item frequency-source -- request to H/W
+  \item frequency-lock-lost -- notification from H/W
 \end{itemize*}

-\subsection{Rx/Tx Delays Calibration}

+\subsection{Rx/Tx Delays Calibration}
+\label{chap:DelaysCalibration}
 A port which is capable of tx/rx internal delays calibration (i.e. measurement) can 
 request assistance from the path-partner in calibration process. Protocol-wise, such 
 calibration shall be defined in this clause.
@@ -200,14 +217,4 @@ UNCALIBRATED state (if implemented) each time it synchronizes to a new MASTER po
 i.e. when the physical link is (re-)connected or a "better" grandmaster is connected to the 
 communication path.

-\subsection{Multi-slave boundary clock}
-\label{chap:multiSlaveBC}
-
-This option enables a BC to have many ports in a SLAVE state. One of the SLAVE ports is 
-a so-called Primary Slave -- provides the source of time (and frequency) for the BC. Any 
-other port in the SLAVE state is considered a Secondary Slave - in normal operation, 
-it does not provide time (and frequency) to the BC but synchronizes (and syntonizes) to the 
-path-partner and acts as a hot-spare in case the Primary Slave breaks.
-A port becomes a Secondary Slave if it is recommended by the State Decision Algorithm 
-(also SDA modified per clause~\ref{chap:modifiedSDA}) to enter PASSIVE state.

--- a/documents/WR_changes_for_PTPv3/highAccuracyProfile.tex
+++ b/documents/WR_changes_for_PTPv3/highAccuracyProfile.tex
-\section{High Accuracy Profile}
+\section{Default High Accuracy Profile}
 \label{chap:highAccuracyProfile}

+The \textit{High Accuracy Default Profile} uses the \textit{High Accuracy Options} to enable 
+high quality synchronization. It defines hardware requirements for the device implementing
+the profile and how the \textit{High Accuracy Options} shall be combined along with 
+other PTP configuration to achieve sub-nanosecond accuracy of sychronization. 
+
+\subsection{Hardware Requirements}
+
+The hardware which is required to suppor this profile shall 
+\begin{itemize*}
+  \item transfer frequency over Layer 1 (e.g. SyncE \cite{SynchE})
+  \item feature constant rx/tx latencies during operation (except for temperature-induced 
+        chagnes) 
+  \item provide higher layers with information about rx/tx latency values - using
+        calibration procedure or without
+  \item provide timestamps with a sufficient precision (i.e. $<$ 100ps) - this might be 
+        achived using phase measurement techniques for sub LSB precision. 
+  \item provide calibration pattern (defined in transport annex for a given mapping).
+\end{itemize*}
+
+\subsection{Announce Message Suffix}
+Clocks (i.e. TC, OC) supporting High Accuracy Profile shall append their 
+Announce Messages with the suffix defined in this clause. Such devices shall also handle 
+properly the suffix which enables recognision of High Accuracy capable devices.
+
+Except for High Accuracy profile capabilities recognision, the suffix conveys 
+the following information:
+\begin{itemize*}
+%   \item Magic Number
+%   \item Version Number (can be different for non-default High Accuracy Profiles)
+%   \item Message ID (ID is used over all High Accuracy options/profiles)
+  \item \textcolor{gray}{Explicit configuration port state (portDS.configState) of the 
+        transmiting port}
+  \item \textcolor{gray}{Calibrated flag set to 1 if the internal fixed delays are known and
+        calibration is not needed}
+  \item \textcolor{black}{High Accuracy ON - flag set to 1 if the High Accuracy path is already 
+        established, i.e.: receiving port passed through UNCALIBRATED state in which it 
+        syntonized over Layer 1 and the value of internal delays has been exchanged. This 
+        flag is used mainly to enforce by the MASTER re-calibration and re-syntonization of 
+        a path.}
+\end{itemize*}
+
+A High Accuracy Communication Path is considred established between two ports implementing
+this profile if:
+\begin{itemize*}
+  \item the ports are connected by direct link (no other devices on the Communiation Path)
+  \item the ports are syntonized over Layer 1 
+  \item the SLAVE port has the knowledge about internal tx/rx delays (obtained/exchanged using 
+        clause~\ref{chap:DelaysCalibration})
+  \item the SLAVE port is in the SLAVE state and the MASTER port is in the MASTER state.
+\end{itemize*}
+
+\subsection{Establishing High Accuracy Communciation Path}
+
+\subsection{Port in MASTER state}
+The following steps shall be performed to establish High Accuracy Communication Path
+\begin{enumerate*}
+  \item 
+  \item 
+  \item 
+  \item 
+\end{enumerate*}
+
+\subsection{Port recommended to be in SLAVE state (in UNCALIBRATED state)}
+The following steps shall be performed to establish High Accuracy Communication Path
+\begin{enumerate*}
+  \item 
+  \item 
+  \item 
+  \item 
+\end{enumerate*}
+

--- a/documents/WR_changes_for_PTPv3/openQuestions.tex
+++ b/documents/WR_changes_for_PTPv3/openQuestions.tex
 \section{Open Questions}
-\label{chap:openQuestions}
\ No newline at end of file
+\label{chap:openQuestions}
+
+\subsection{Multi-slave boundary clock}
+\label{chap:multiSlaveBC}
+
+This option enables a BC to have many ports in a SLAVE state. One of the SLAVE ports is 
+a so-called Primary Slave -- provides the source of time (and frequency) for the BC. Any 
+other port in the SLAVE state is considered a Secondary Slave - in normal operation, 
+it does not provide time (and frequency) to the BC but synchronizes (and syntonizes) to the 
+path-partner and acts as a hot-spare in case the Primary Slave breaks.
+A port becomes a Secondary Slave if it is recommended by the State Decision Algorithm 
+(also SDA modified per clause~\ref{chap:modifiedSDA}) to enter PASSIVE state.
\ No newline at end of file