Hash Key Type 4: 2-Tuple

Napatech Link-Capture™ Software Features

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

Hash key data

Hash key type 4 is a 2-tuple where the hash key data is the contents of these packet header fields:

  • 32-bit IPv4 / 128-bit IPv6 source address
  • 32-bit IPv4 / 128-bit IPv6 destination address

For IPv4 packets, hash key data word 0 is always the IPv4 source address, and hash key data word 4 is always the IPv4 destination address. For IPv6 packets, hash key data words 0 – 3 are always the IPv6 source address, and hash key data words 4 – 7 are always the IPv6 destination address. This means that frames sent from IP address A to IP address B will generate a hash value different from frames sent from IP address B to IP address A (if address A and B are different).

Note: The source and destination addresses can be swapped (see Tuple Swap).

For IPv4 packets, hash key data words 1 – 3 and 5 – 9 are all zeros for hash key type 4. For IPv6 packets, hash key data words 8 and 9 are all zeros for hash key type 4.

Illustration for IPv4 packets

This figure illustrates hash key type 4 for IPv4 packets.

2-tuple hash key for IPv4

Illustration for IPv6 packets

This figure illustrates hash key type 4 for IPv6 packets.

2-tuple hash key for IPv6

Validity

Hash key type 4 is valid for frames containing an IPv4 packet or an IPv6 packet.