The 'nic_perf' component is a benchmark component for the Nic and Uplink
service. It can act as a Nic/Uplink server and a Nic client. The component
periodically logs the number of transmitted/received packets and the resulting
data rate. When enabled, it transmits continuous stream of UDP packets to a
predefined receiver as a test stimulus.


Basics
~~~~~~

This is an example configuration:

! <config period_ms="5000" count="10000">
!    <default-policy>
!       <tx mtu="1500" to="10.0.1.2" udp_port="12345"/>
!    </default-policy>
!    <nic-client>
!       <interface ip="10.0.2.1" dhcp_client_ip="10.0.2.2"/>
!    </nic-client>
! </config>

The 'period_ms' attribute specifies the logging intervall (in milliseconds). By
default, logging is disabled. The 'count' attribute defines after how may
periods the component exits. Session policies for connecting Nic/Uplink clients
are specified by '<policy>' nodes resp. a '<default-policy>' node. The component
opens a single Nic connection if a '<nic-client>' node is provided.

All sub-nodes comprise an optional '<interface>' node and an optional '<tx>'
node. This is an overview of their attributes:

:interface.ip:
  Optional. Specifies the own IP address. If not specified, the component will
  send DHCP requests to acquire an IP.

:interface.dhcp_client_ip:
  Optional. If specified, the component responds to DHCP requests with this IP
  address.

:tx.mtu:
  Optional. Sets the size of the transmitted test packets.

:tx.to:
  Mandatory. Specifies the destination IP address.

:tx.udp_port:
  Mandatory. Specifies the destination port.
