ISL Classification

Napatech Link-Capture™ Software Features

Intel® PAC
Napatech SmartNIC
Content Type
Feature Description
Capture Software Version
Link™ Capture Software 12.10

ISL frames

The frame decoder recognizes an ISL-encapsulated frame if the frame being analyzed has a destination MAC address equal to 01:00:0C:00:00:0X or 03:00:0C:00:00:0X.

Note: A single packet cannot be recognized both as an ISL-encapsulated frame and a CFP-encapsulated frame. For packets with both encapsulations, the outermost encapsulation is decoded and the inner layer 2 packet is decoded as EtherII (for recognized CFP encapsulation) or SNAP (for recognized ISL encapsulation), and further decoding is stopped.

ISL length

The length of the ISL field is 26 bytes before the encapsulated Ethernet frame and 4 bytes of ISL CRC after the Ethernet frame.