| 摘要 |
<p>Network nodes of a packet transmission network send to other network nodes link state messages indicating themselves, network nodes adjacent to themselves, and metrics of links connecting themselves to their adjacent network nodes. A first and a second network node each support a first and a second network protocol, and they are connected by a path containing intermediate network nodes not supporting the first network protocol. A tunnel path between the network nodes is provided. The tunnel path is advertised, by sending a link state message indicating a pseudo network node as a network node located between the first and the second network node, and as a network node supporting the first but not the second network protocol, A metric indicated in the link state message is chosen such, that an overall metric of said tunnel path is equal to or greater than an overall metric of the path containing the intermediate network nodes.</p> |
