The way ISIS identifies the Line within the system is through a three digit number CMS account. It corresponds to the company that is going to be in charge of the transportation of the cargo, and it could be the same main company. It is very important at the moment of the creation of the job, vessels and line/port master files.

There is a line defaults table which similar to the traffic system file, defines stevedore, trucker numbers, and basically a setup that will be taken into account by the different programs to make the system behave in a specific way. SCAC code is also defined in this table