|  | 1.4 | Routing Protocol
| 1.4.3 | Classes of routing protocols
Most routing protocols are based on one of two routing algorithms: distance vector or link state. The distance vector routing approach determines the direction (vector) and distance to any link in the internetwork. The link-state (also called shortest path first) approach re-creates the exact topology of the entire internetwork (or at least the portion in which the router is situated). The balanced hybrid approach combines aspects of the link-state and distance vector algorithms. The next several pages cover procedures and problems for each of these routing algorithms and present techniques for minimizing the problems.