Ethernet splitter.variant cable saver. Need to be well shielded. Does not work on 1G networks.
Take the other end of the cable, cut it to 9 inches and punch down the four pairs using the following wiring scheme: You will need two of them.
1 White/Orange to pin 1keystone jack
2 Orange to pin 2 keystone jack
3 White/Green to pin 3 keystone jack
6 Green to pin 6 keystone jack
4 Blue to pin 2 keystone jack
5 White/Blue to pin 1 keystone jack
7 White/Brown to pin 3 keystone jack
8 Brown to pin 6 keystone jack
Once all the pairs are punched down, you can glue together side by side the two keystone jacks.