The first two options display packet information on the console.This is ideal if a moderate amount of traffic is being monitored.Plans for future phase: Add support at the CPP server.The advantage of those methods is that they can be easily extended to simulate a large number of clients in automation.In some complex cases, Scapy may rebuild the header. The Field Engine has a cost in CPU resources: CPU cycles and CPU memory bandwidth (bandwidth available for CPU to read from or write to memory).It is possible to significantly improve performance by caching the packets and running the Field Engine offline (before sending the packets).
Current: TRex supports scanning of network for IPv6-enabled neighbors, and pinging nearby devices from the console.
An example of a scenario that cannot use this method, due to the packet limitation, is a program that changes the src_ip randomly.
Pre-caching a limited number of packets would not be compatible with continuously varying the src_ip randomly.
This example FE program is fully compatible with pre-caching - the traffic output is exactly the same as when running without pre-caching.
Caching the packets enables the program to run 2 to 5 times faster.
For example, a queue of 1 million packets can be allocated as a cyclic queue and be active with a rate of couple of MPPS.