Connection tracking netlink interface

modulename: nf_conntrack_netlink.ko

configname: CONFIG_NF_CT_NETLINK

Linux Kernel Configuration
└─>Networking support
└─>Networking options
└─>Network packet filtering framework (Netfilter)
└─>Core Netfilter Configuration
└─>Connection tracking netlink interface
In linux kernel since version 2.6.16 (release Date: 2006-03-19)  
This option enables support for a netlink-based userspace interface

source code: