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Spirent TestCenter : How to create multiple IPv6 Neighbor Solicitation messages using Raw Streamblocks?


Spirent TestCenter


When there are many IPv6 neighbors, Neighbor Discovery could take a lot of time to process in TestCenter.
Work Around is to use raw streams and create a Neighbor Solicitation message.

We can't use the normal IPv6 Neighbor Solicitation to generate multiple messages due to the checksum decrements and there is no modifier for the checksum.
So we need to create a custom packet.
We can do a capture of the first ND to get a baseline, then create the custom packet as described below.

1. First start off with a normal NS packet to get the corresponding capture.
2. Next get the capture
3. Copy the ICMPv6 bytes from packet (Right click->Copy->Bytes (Hex Stream)
4. Now create a Custom Header under the IPv6 Header instead of the ND.
5. Paste the copied bytes from the Wireshark capture as custom header content.

The checksum is offset by 2 bytes in hex stream
Then we want to decrement the value, the value we start with is the value we got from the first packet in the capture with the good checksum.
Add the modifier as below




  • The IPv6 Header Source address RangeModifier count should be the same as the the Custom Header Modifier count.
  • Be aware to set the IPv6 next header to ICMP and of possible other changes such as using Target Link Layer instead of Source that may be needed for your specific test.


Product : Spirent TestCenter,Spirent TestCenter,PGA