Hash Key Type 4: 2-Tuple

Napatech Link™ Software Features
Platform
Napatech SmartNIC
Content Type
Feature Description
Capture Software Version
Link™ Capture Software 12.0

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

The hash key data is not sorted for hash key type 4. 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 IPv 4 packet header Ver . & IHL T o S Total l ength Identification F Fragment offset TTL Prot . Header checksum Source address Destination address Options 0 4 8 12 16 20 32 - bit IPv 4 source address 0 1 Hash key data word 0 2 0 3 0 4 32 - bit IPv 4 destination address

Illustration for IPv6 packets

This figure illustrates hash key type 4 for IPv6 packets.

2 - tuple hash key IPv 6 packet header Ver . & Pri . Flow label Length Next header Hop limit Source address Destination address 0 4 8 12 16 20 128 - bit IPv 6 source address 0 , 1 , 2 , & 3 Hash key data word 128 - bit IPv 6 destination address 24 28 32 36 40 4 , 5 , 6 & 7

Validity

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