What VPN client Leap 15 ?

I am confused. I have been given a abcd.conf file where I can see below:

IPSec gateway xx.xx.xx.x
IPSec ID xxxxxxxxxx
IPSec secret xxxxxxx
Xauth username xxxxxxx
Xauth password xxxxx
Interface MTU xxxx

I cant find any suitable application to insert this configuration.

Can anyone give me some direction?

This is Cisco VPN, you may try vpnc (command line or as plugin to Network Manager).

Why not try to use VPN? I have no troubles since I’ve got one according to the bestvpnrating list.