Local Retransmission with Embedded Time Stamp

Feature Set N-ANL10

Platform
Napatech SmartNIC
Content Type
Feature Description
Capture Software Version
N-ANL10

Local retransmission with embedded time stamp appends a high precision time stamp from the capture port to retransmitted frames.

Purpose

By delivering a high precision time stamp to downlink appliances, local retransmission with embedded time stamp minimizes the need for expensive load distribution switch ports.

Features

The retransmitted frames are expanded to include a trailer with a time stamp, and a new FCS is calculated and added. The Unix-based time stamp format has a resolution of 1 ns and represents time as a 64-bit unsigned integer value, starting from January 1, 1970.

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Limitations

Limitations for local retransmissions with embedded time stamp are similar to limitations for local retransmission. See Local Retransmission.

Frames are expanded 12 bytes, which increase the risk of oversubscription of the TX port and packet loss.

Configuration interface

The local retransmission with time stamp functionality is configured using NTPL.

Example

In this NTPL example, all traffic received on port 0 is retransmitted with embedded time stamp on port 1.

Assign[DestinationPort=1; TxMetaData=TimeStamp] = Port==0