Provided is a bearing with a magnetic fluid seal reliably maintaining sealing of a rolling element section in the bearing and having a structure ensuring high productivity. A node, which has received a message including a hop-count of the LSP from an upstream node or a downstream node, determines whether or not the node itself is to update the TTL value in a packet if received through the LSP. The system includes a laser, a controller selecting at least first and second patterns, and a scanner operable in response to the controller. A stopper is in fluid-tight engagement inside the barrel.