AN 739: Altera 1588 System Solution

ID 683410
Date 1/28/2016
Document Table of Contents Packet Parser

The Ethernet Packet Classifier functions as a packet parser module for Altera Ethernet MAC-based 1588 system. In the transmit direction, the Packet Parser module is used to determine the type of packet being sent, determine the appropriate location for the time stamp field and provide this information via a command to the 1588 MAC transmitter for further processing. The module is also able to provide the information of the timestamp offset and whether there is an update to the IPv6 UDP correction field.

In the receive direction, this block checks whether the local timestamp of the packet received on the Ethernet MAC receiver is indeed for a PTP packet. For example, the 1588 PTP packet’s timestamp field location relative to the Start Of Packet (SOP) is different for a PTP packet encapsulated over Ethernet versus for a PTP packet encapsulated over UDP over IPv6 over Ethernet.