Ethernet connection problems

Two punch down jacks [monoprice.com], one surface mount keystone block [monoprice.com], one punch down tool [monoprice.com], and very careful use of razor blade or stripper [monoprice.com] should do the job.

Use the T569B color code on both ends of the cable. Use the surface mount box to secure the keystone in your structured wiring cabinet (you don't have anything else available in the cabinet you could terminate it to). Connect one of your unused patch cables or other spare ethernet cables from the jack to the router.

Similar tools and products are available at your local hardware store. If you acquire a different type of surface mount jack, make certain the wire connections are in a punch down block and that it says Cat-5/5e like these keystone jacks otherwise it won't work for data applications (it's a phone jack).

Start with the end of the cable in the wiring cabinet. Search the net for text and video tutorials, "how to install cat5e punch down jack". Locally your best options would be microcenter and frys, make sure whatever punch down tool you get cuts the wire.