U.S. domestic oil and gas production is higher than it's been in decades, and as a result, the midstream industry is booming as well. But headline hogs such as Kinder Morgan (NYSE:KMI) and TransCanada (NYSE:TRP) aren't doing all the work. In this video, energy analyst Aimee Duffy takes a look at Pembina Pipeline (NYSE:PBA) and Boardwalk Pipeline Partners (NYSE:BWP), two lower-profile midstream outfits that may be right for your portfolio.