You have a few options when it comes to studying for your Cisco exams, and each choice has its own pros and cons.
Live equipment is ideal but can prove expensive and of course, you have to find a valid (and current) IOS. You have to find somewhere to store it and pay for all the power use as well as put up with the fan noise. For CCNP level, you are looking at four switches and at least five routers.
GNS3 is by now, world-famous but comes with a few drawbacks. You still have to find a valid IOS, only certain models work without crashing, the download file is huge, and there is no switching. So for all your STP, switchport security, etc. you have to find another solution.
Live rack rental is a great choice. You can pay for rack time by the hour and most rack rental services offer the latest equipment and IOS release. The drawbacks are having to pay for it and having to find a free time slot and getting connected can prove somewhat fiddly. But this is the only real option for CCIE level studies.
Rack simulator. These should have been killed off years ago but they still in existence. Basically a software version of switches and routers but it doesn’t run IOS. The programmer creates a set of permitted commands, and the output is also created in software. You are limited in your topology choice, and no matter how hard they try, it will never be like working on live equipment.
The final choice is Packet Tracer, which was created by Cisco to be used by Cisco Network Academy students and was only legally available to them. Until now that is.
Cisco has now released PT to the general public. It’s a network simulation program but offers unlimited topologies, runs the latest IOS version and gives you the choice to use layer 2 or multi-layer switches and various models of routers. You can add PCs and servers as well as network sniffers and use the IOS licensing commands required by the exam syllabus.
PT is designed for CCNA RS and CCNA Security so doesn’t offer all the features you need for CCNP, and there are a few drawbacks even for CCNA however, it’s around 95% what you need for CCNA level studies. You can make up the shortfall with a few hours of online rack rental.
PT runs on Linux or Windows, and there is also an App available. Here is the download link:
This will pretty much kill the network simulation market, and it will even dent GNS3 use (although it’s free to use).
You will have to create a free account to get access, but you get access to a free PT training course. If you are studying for the CCNA or CCNA Security, then check it out now.