CONFIG_IP_DCCP_TFRC_LIB (not configurable)

configname: CONFIG_IP_DCCP_TFRC_LIB

Linux Kernel Configuration
└─>Networking support
└─>Networking options
└─>The DCCP Protocol (EXPERIMENTAL)
└─>DCCP CCIDs Configuration (EXPERIMENTAL)
└─>IP_DCCP_TFRC_LIB
In linux kernel since version 2.6.14 (release Date: 2005-10-27)  
depends
CONFIG_EXPERIMENTAL
CONFIG_IP_DCCP
CONFIG_NET

is depended by
CONFIG_IP_DCCP_CCID3