Trust Router v1.x only supports static peering. This means that the peer, or upstream, Trust Router, is statically defined in the peering configuration. Static peering currently only supports a hub-and-spoke model, of which is the hub. Dynamic peering, in which Trust Routers can dynamically build routes to other Trust Routers in the system, is available in Trust Router v2.x. 

The peering configuration is stored in peering.cfg, which is placed next to main.cfg in /etc/trust_router/conf.d/[instance]

An example static peering.cfg is below:

Static peering also has some performance implications that affect authentication performance. Please see Trust Router Static Peering Performance Statistics for more information.