EstiNet 8.0 OpenFlow network simulator and emulator is the best OpenFlow network simulator and emulator in the world for doing Software Defined Networks research. It can accurately simulate thousands of Ver 1.1.0 and Ver 1.0.0 OpenFlow switches (supports for Ver 1.2.0 and Ver 1.3.0 are underway). It supports both of the simulation mode and the emulation mode. In the simulation mode, the real-world open source OpenFlow controller NOX/POX/Floodlight application programs can directly run up on a controller node in the simulated network to control these simulated OpenFlow switches without any modification. In the emulation mode, the NOX/POX/Floodlight controller application programs can run up on an external machine that is different from the machine used to simulate OpenFlow switches to control these simulated OpenFlow switches. In additiion, in the emulation mode, if an OpenFlow controller has been implemented as a dedicated hardware device, it can remotely control the simulated OpenFlow switches in EstiNet 8.0 via a network.  

EstiNet 8.0 OpenFlow network simulator and emulator simulates the interactions between the NOX/POX/Floodlight controller application programs and the simulated OpenFlow switches accurately, quickly, and repeatably. An OpenFlow researcher can easily and efficiently test his own NOX/POX/Floodlight controller application programs on an EstiNet simultaed OpenFlow network. He can run up his modified NOX/POX/Floodlight controller application programs on an EstiNet simulated OpenFlow network without any modification! (This unique capability is due to the innovative "kernel-reentering simulation methodology" used by EstiNet.)  Comparing other existing OpenFlow simulators and emulators, one will find that EstiNet 8.0 OpenFlow networrk simulator and emulator is the most accurate, fast, scalable, and useful OpenFlow network simulator and emulator in the world.

For example, although Mininet OpenFlow emulator can be used as a rapid prototyping for Software-Defined Networks, it has several serious drawbacks and limitations. As said in its own technical paper published in ACM Hotnets 2010, the most significant limitation of Mininet is its lack of performance fidelity because it provides no guarantee that a host in Mininet  that is ready to send a packet will be scheduled promply to send the packet and it provides no guarantee that all switches in Mininet will forward packets at the same rate. The packet forwarding capability of a switch in Mininet is unpredictable as it depends on the numbers of hosts and switches that must be multiplexed over a CPU in Mininet. As a result, Mininet can only be used to test the behavior of a controller application program but cannot be used to study any network/application performance (e.g., end-to-end achieved throughput or experienced delay) of a data flow in an OpenFlow network controlled by the controller. 

In contrast, EstiNet 8.0, when running in the simulation mode, accurately simulates the properties of the links that connect simulated OpenFlow switches. These properties include link bandwidth, link delay, link downtime, and the medium access control (MAC) protocol used over the link (e.g., IEEE 802.3 or IEEE 802.11, etc.). As a result, performance evaluation of data flows or the whole OpenFlow network can be accurately studied in EstiNet 8.0. Furthermore, since during simulation, the advancement of the simulation clock is accurately controlled by EstiNet 8.0, the performance simulation results of EstiNet 8.0 are always realistic and repeatable, totally unaffected by the number of OpenFlow switches and hosts simulated by it. These unique and superior properties are in sharp contrast to those of Mininet and other OpenFlow network simulators and emulators.