RFC 3588:Diameter Base Protocol
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12. Diameter protocol related configurable parameters

   This section contains the configurable parameters that are found
   throughout this document:

   Diameter Peer
      A Diameter entity MAY communicate with peers that are statically
      configured.  A statically configured Diameter peer would require
      that either the IP address or the fully qualified domain name
      (FQDN) be supplied, which would then be used to resolve through
      DNS.

   Realm Routing Table
      A Diameter proxy server routes messages based on the realm portion
      of a Network Access Identifier (NAI).  The server MUST have a
      table of Realm Names, and the address of the peer to which the
      message must be forwarded to.  The routing table MAY also include
      a "default route", which is typically used for all messages that
      cannot be locally processed.

   Tc timer
      The Tc timer controls the frequency that transport connection
      attempts are done to a peer with whom no active transport
      connection exists.  The recommended value is 30 seconds.

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