pgRouting is an extension of PostGIS and adds routing functionality to PostGIS/PostgreSQL. pgRouting provides following functions: Dikstra - routing algorithm without heuristics; A-Star - routing for large datasets (with heuristics); Shooting-Star - routing with turn restrictions (with heuristics); Traveling Salesperson Problem (TSP); Driving Distance calculation (Isolines).
pgRouting functions can be added to any PostGIS database. For detailed manual please refer to pgRpouting website.