User Manual

External Network Connectors

External Network Connectors allow access to external networks or testbeds. A list of available external networks to choose from is available at External Network under the Resources entry in the main menu. (→ go now)

External network elements are located on a host, which acts as a gateway. If the external network is located on a different site than the rest of the connected elements, packets are forwarded to this site and hence have a higher delay.

Network segments should not have multiple network exits. This could cause loops in the network and result in network crashes.


An external network connector element has the following configuration options


The kind of an external network defines to what network type the tunnel connects to. ToMaTo uses a hierarchical order for network kinds.

For example: If you choose an external network of kind Internet, ToMaTo may use any host on any site to act as a gateway. Whereas when selecting an external network of kind Internet (TU KL), this would restrict the gateway selection to a host from the TU KL site.

Same Network

This option forces external networks which use the above mentioned hierarchical order to use the same subkind.