the fmcsa regulates the length, width, and weight limits of cmvs for "interstate" commercial traffic. interstate commercial traffic is generally limited to a network of interstate freeways, u.s. highways and state highways known as the national network (nn). provided the truck remains on the nn, they are not subject to the state limits. state limits (which can be lower or higher than federal limits) come into effect for "intrastate" commercial traffic, provided the vehicle is "not" on the nn.