METHOD AND DEVICE FOR ESTABLISHING MULTICAST PATH

Embodiments of the present invention disclose a method and an apparatus for establishing a multicast path. The method includes: when computing a multicast branch path to a first leaf node by using a constraint fails, degrading the constraint to obtain a secondary constraint; computing a multicast branch path to the first leaf node according to the secondary constraint; and establishing a multicast branch path to the first leaf node according to the multicast branch path obtained by computation. By using the method and apparatus for establishing a multicast path according to the embodiments of the present invention, for a leaf node to which a multicast path cannot be established according to a primary constraint, a substitute multicast path is established according to a secondary constraint, which ensures that service traffic can reach all leaf nodes in a multicast service and that the multicast service for the leaf nodes is quickly recovered when a fault occurs.