Device and method for restoring connections in automatically switchable optical networks

The optical communication network (8) as claimed in one of the preceding claims, in which the distance between the fourth network node device (3) and the second network node device (6) is additionally taken into consideration in the determination as to whether the fourth network node device (2) is responsible for setting up the second data link or not.

The optical communication network (8) as claimed in one of the preceding claims, in which the distance between the fourth and the third network node device (2, 3) is additionally taken into consideration in the determination as to whether the fourth network node device (2) is responsible for setting up the second data link or not.

The optical communication network (8) as claimed in one of the preceding claims, in which one of the network node devices (2, 3, 4) which is located on the path, used by the first data link, from the fault location in the direction of the network node device (1) which has set up the first data link, is responsible for setting up the second data link.

The optical communication network (8) as claimed in one of the preceding claims, in which the parameter (NRR) determined by the third network node device (3) or a further parameter (n) transmitted to the fourth network node device (2) contains information on whether the third network node device (3) has received a further signaling signal (S31), corresponding to the signaling signal (S32), from a further network node device (4) connected to the third network node device (3).

An optical communication network (20) in which optical signals are exchanged via a first data link between a first network node device (1) and a second network node device (6) with interposition of a number of further interconnected network node devices (2, 3, 4, 5), characterized in that, after a disturbance on the first data link, a third network node device (3) sends a signaling signal (S32) to a fourth network node device (2) connected to the third network node device (3) for setting up a second data link which acts at least partially as a standby for the first data link, and the fourth network node device (2) determines on the basis of a Bernoulli experiment whether it is responsible for setting up the second data link or not.

The optical communication network (20) as claimed in one of the preceding claims, in which the second data link extends wholly or partially via a different undisturbed path from the first data link.

An optical information transmission method in which optical signals are exchanged via a first data link between a first network node device (1) and a second network node device (6) with interposition of a number of further interconnected network node devices (2, 3, 4, 5), characterized in that, after a disturbance on the first data link, a third network node device (3) sends a signaling signal (S32) to a fourth network node device (2) connected to the third network node device (3) for setting up a second data link which acts at least partially as a standby for the first data link, which signaling signal (S32) contains a parameter (NRR, n) determined by the third network node device (3) on the basis of which it is determined whether the fourth network node device (2) is responsible for setting up the second data link or not.