Method and a device for defining implementation of a look-up table for a network element of a software-defined network

A network element for a software-defined network, the network element comprising:

• a data transfer interface for receiving data and for transmitting data, the received data specifying a look-up table to be implemented in the network element,
• hardware for implementing the look-up table in two or more mutually alternative ways, and
• a device for defining implementation of the look-up table, the device comprising a processing system adapted to:
• receive one or more first data items providing information about one or more look-up keys of the look-up table,
• receive one or more second data items indicating at least one of the following:
• the maximum number of entries of the look-up table, an average time between successive look-ups from the look-up table, an average time between successive modifications of the look-up table, and
• select one of the two or more mutually alternative ways to implement the look-up table on the basis of the hardware available for implementing the look-up table, the one or more first data items, and the one or more second data items.

A software-defined network comprising:

• a controller system for transmitting configuration data to the one or more network elements so as to configure the one or more network elements, the configuration data specifying a look-up table to be implemented in the one or more network elements, and
• one or more network elements,
• wherein each of the network elements comprises:
• a data transfer interface for receiving data and for transmitting data, the received data specifying a look-up table to be implemented in the network element,
• hardware for implementing the look-up table in two or more mutually alternative ways, and
• a device for defining implementation of the look-up table, the device comprising a processing system adapted to:
• receive one or more first data items providing information about one or more look-up keys of the look-up table,
• receive one or more second data items indicating at least one of the following:
• the maximum number of entries of the look-up table, an average time between successive look-ups from the look-up table, an average time between successive modifications of the look-up table, and
• select one of the two or more mutually alternative ways to implement the look-up table on the basis of the hardware available for implementing the look-up table, the one or more first data items, and the one or more second data items.