Dynamips

Dynamips is a software to emulate Cisco hardware on a conventional PC. It is important that Dynamips does not emulate the entire router, but only the hardware (analogous to VMware for conventional PCs). This means that a suitable IOS is required to use Dynamips can.

Functionality

Dynamips was originally intended as an emulator for a 7200 router, but now emulates the following devices:

• Cisco 7200
• Cisco 3600 series ( 3620, 3640, 3660 )
• Cisco 3700 series ( 3725, 3745 )
• Cisco 2600 series ( 2610 to 2650XM, 2691 )

Additionally Dynamips offers the possibility of the virtual devices with additional plug-in modules (NPE -400, PA 8T, NM -4E, NM 16ESW, NM 1FE TX to name but a few) provide their corresponding slots available.

The system supports a variety of IOS versions, to 12.2s and 12.4T.

Since there is no console port to manage a virtual router, the CLI can be operated via telnet to the host computer.

The interfaces of the virtual router can be linked to real network interfaces. This creates the possibility of real hosts through virtual router networks to join.

Other software

To reduce the operation of Dynamips in its complexity, Dynagen was created as a text-based front-end for Dynamips. To use Dynagen Dynamips must be started in the so-called hypervisor mode. It then managed with an instance of multiple routers simultaneously.

Dynagen makes it possible for complex router networks using very simple configuration files to create. A simple example might look like this:

[ localhost: 7201 ]   [ ]    image = C7200 - jk9o3s - mz.124 - 7a.image.bin    npe = npe -400    ram = 160   [ [ router R1] ]    model = 7200    slot1 = NM -4E   [ [ router R2] ]    model = 7200    slot1 = NM -4E    e0 / 1 = R1 e0 / 1 In this example, on the local Dynamips server (which here differs from the default port 7200 to port 7201 is running) defines a model 7200 with details of the image file to use for the expansion module NPE -400 and 160MB RAM memory of the two instances be created R1 and R2 each with a 4- port Ethernet module NM- 4E. The interface Ethernet0 / 1 Router R2 is connected to Ethernet0 / 1 of R1. It is sufficient to establish this connection on one of the two terminals. By default, the devices are created by telnet in the order given, starting from port 2000 to reach the host computer. In this case, R1 at port 2000 R2 on port 2001.

The configuration file also allows you to create simple switches that enable multiple ports can be connected together.

As a graphical user interface for Dynamips and Dynagen GNS - 3 was developed. GNS -3 allows a complex configuration of the virtual environment via a simple graphical interface.