A very determined individual has completed a functioning Cisco 7200 Series Router simulator.

The emulator runs a large number of Cisco IOS releases including the recent 12.4, you will however need to have your own IOS image. The creator states that while his emulator cannot replace a real router, it can be a complimentary tool to real labs for administrators of Cisco networks or individuals wanting to pass their CCNA CCNP CCIE exams.

There is both Windows and Linux executable's available for download.

Details and downloads can be found here Cisco 7200 Simulator 

Information below is directly from the creator IPFlow

Introduction

I started recently (August 2005) a project to emulate a Cisco 7200 on a traditionnal PC. This kind of emulator would be useful to:

• Be used as a training platform, with software used in real world. It would allow people to become more familiar with Cisco devices, Cisco being the world leader in networking technologies ;
• Test and experiment features of Cisco IOS ;
• Check quickly configurations to be deployed later on real routers.

Of course, this emulator cannot replace a real router, it is simply a complementary tool to real labs for administrators of Cisco networks or people wanting to pass their CCNA/CCNP/CCIE exams.

Current status

At this time, the emulator I have programmed is able to boot a large number of Cisco IOS releases available for the 7200 platform, including the latest 12.2S and 12.4.

The following devices are emulated in the current release (0.2.4):

• MIPS64 CPU processor. The instruction set is not completely emulated now (FPU support is lacking, TLB support is not finished and other minor things), but it is sufficient for IOS ;
• DRAM and Packet SRAM memory ;
• Non-Volatile Memory (NVRAM) ;
• Signetics SCN 2681 DUART (Console and AUX ports);
• Dallas DS1620 Temperature Sensors and Voltage Sensors, allowing the Environmental Monitor to work properly ;
• NMC93C46 Serial EEPROM ;
• Bootflash of 8 Mb (Intel 28F016SA) ;
• I/O and Midplane FPGA specific to the C7200 platform ;
• Basic Galileo GT64010/GT64120 PCI controller, DEC 21x50 PCI bridges and so.
• Ethernet cards "C7200-IO-FE" and "PA-FE-TX" based on DEC21140 chip ;
• ATM card "PA-A1" based on Texas Instruments Tneta1570 chip ;
• Serial cards "PA-4T+" and "PA-8T"

New features in 0.2.4:

• Serial interface support to allow use of PPP/HDLC/Frame-Relay encapsulations
• Virtual Frame-Relay switch with basic LMI support (ANSI Annex D)

Download

The current release is 0.2.4, published Feb 14, 2006 (you can consult the README file (http://www.ipflow.utc.fr/dynamips/README-0.2.4.txt)).

You have to download only one binary file corresponding to your architecture:

• Executable for Linux/x86 (http://www.ipflow.utc.fr/dynamips/dynamips-0.2.4-x86.bin)
• Executable for Linux/x86_64 (AMD64 and EM64T) (http://www.ipflow.utc.fr/dynamips/dynamips-0.2.4-amd64.bin)
• Executable for Windows (with Cygwin DLL) (http://www.ipflow.utc.fr/dynamips/dynamips-0.2.4-cygwin.zip)

If you are using the Windows version, you have to download and install the WinPcap library (http://www.winpcap.org/). It is now possible to access the Ethernet card of host machine to send/receive packets on the LAN.

You can also download the source code, published under the GNU General Public Licence (GPL):

• The source code of release v0.2.4 (http://www.ipflow.utc.fr/dynamips/dynamips-0.2.4.tar.gz)