Which NICs do you support?

Basic functionality is available on all NICs supported by DPDK. Hardware timestamping is currently supported and tested on Intel 82599, X540 and 82580 chips. Hardware rate control is supported and tested on Intel 82599 and X540 chips.

How is MoonGen different from SnabbSwitch?

SnabbSwitch is a framework for packet-processing in Lua. There are a few important differences:

MoonGen comes with explicit multi-core support in its API, SnabbSwitch does not
MoonGen focuses on efficient packet generation, SnabbSwitch is a more generic framework
Our API is designed for packet-generation tasks, i.e. writing a packet generator script for MoonGen is a lot easier than writing one for SnabbSwitch
We implement driver-like functionality for hardware functions required by packet generators: timestamping, rate control, and packet filtering
SnabbSwitch reimplements the NIC driver in Lua, we rely on the DPDK driver for most parts

Why does MoonGen use DPDK instead of SnabbSwitch as driver?

We decided for DPDK as back end for the following reasons:

DPDK is faster for raw packet IO. This is not really a drawback for the use cases SnabbSwitch is designed for where IO is only a small part of the processing. However, for packet generation, especially with small packets, the share of packet IO is significant and the performance of SnabbSwitch is not sufficient here.
DPDK provides a stable and mature code base whereas SnabbSwitch is a relatively young project.
DPDK currently supports more NICs (with stable and mature drivers) than SnabbSwitch. (We do not want to write our own drivers or debug existing ones.)
Lack of multi-core support. (Only possible by starting SnabbSwitch more than once.)

Note that this might change. Using DPDK also comes with disadvantages like its bloated build system and configuration.