Network interfacing method and a network interface for a digital transmission network

Claim 3

The method according to claim 1, wherein said policing function utilizes the leaky bucket function.

Claim 4

The method according to claim 1, wherein each overhead byte comprises at least a cyclic counter value which is equal in all overhead bytes of one cell block and which is incremented by one N from one cell block to another.

Claim 5

The method according to claim 1, wherein the overhead bytes comprise a transmission signal number which is incremented from one overhead byte to another within the same cell block.

Claim 6

The method according to claim 1, wherein N synchronization words are added to the composite signal at intervals of M cell blocks.

Claim 7

Method according to claim 1, characterized in that the transmission signals received over the transmission network are demultiplexed at the reception end and restored to the cell-based signal, the rate of which is adapted to said high nominal bit rate.

Claim 8

The method according to claim 2, wherein each overhead byte comprises at least a cyclic counter value which is equal in all overhead bytes of one cell block and which is incremented by one or N from one cell block to another.

Claim 9

Method according to claim 2, wherein the overhead bytes comprise a transmission signal number which is incremented from one overhead byte to another within the same cell block.

Claim 10

The method according to claim 1, wherein N synchronization words are added to the composite signal at intervals of M cell blocks.

Claim 11

The method according to claim 1, further comprising: demultiplexing the transmission signals received over the transmission network at the reception end and restoring them to the cell-based signal, the rate of which is adapted to said high nominal bit rate.

Claim 12

The method of claim 1, wherein: said high nominal bit rate is 140 or 155 Mbits/s and said separate lower-speed transmission signals each have a bit rate of about 1.5, 2, 6 or 8 Mbits/s.

Claim 13

The method according to claim 1, wherein the multiplexing takes place byte by byte.

Claim 14

A user-network interface in a digital transmission network for a cell-based digital signal comprising cells of fixed length and having a high nominal bit rate, the interface comprising: an input buffer means for receiving and buffering the cell-based signal; a policing means for controlling said buffer means to adapt the rate of the received cell-based signal to the actual transmission speed of the transmission network; a mapping means for forming cell blocks of N consecutive cells from the cell-based signal and for adding N overhead bytes to each cell block; a first multiplexing means for multiplexing the output signal of the mapping means byte by byte into N separate output signals of about 1.5 Mbit/s, 2 Mbit/s, 6 Mbit/s or 8 Mbit/s, N being an integer which is greater than 1.

Claim 15

A user-network interface in a digital transmission network for a cell-based digital signal comprising cells of fixed length and having a high nominal bit rate, the interface comprising: an input buffer means for receiving and buffering the cell-based signal; a policing means for controlling said buffer means to adapt the rate of the received cell-based signal to the actual transmission speed of the transmission network; a mapping means for forming cell blocks of N consecutive cells from the cell-based signal and for adding N overhead bytes to each cell block; a first multiplexing means for multiplexing the output signal of the mapping means byte by byte into N separate output signals of about 1.5 Mbit/s, 2 Mbit/s, 6 Mbit/s or 8 Mbit/s, N being an integer which is greater than 1.

Claim 16

The interface according to claim 13, wherein the network interface further comprises a first generator means for generating empty cells; a second generator means for generating control cells; a combiner means for combining cells from the first and the second generator means with the rate-adapted cell-based signal before applying the signal to the mapping means.

Claim 17

The interface according to claim 14, wherein the network interface further comprises a means for mapping at least one non-cell-based synchronous digital signal to the cells; a buffer means for adapting the rate of the obtained cell-based signal and for applying the rate-adapted signal to the combiner means for combining it with the output signal of the input buffer means.

Claim 18

The interface according to claim 13, further comprising a second multiplexing means for multiplexing the output signals of the first multiplexing means into the STM frames of a synchronous digital hierarchy.

Claim 19

The interface according to claim 13, further comprising a second multiplexing means for multiplexing the output signals of the first multiplexing means into the STM frames of a synchronous digital hierarchy.

Claim 20

The interface according to claim 14, further comprising a second multiplexing means for multiplexing the output signals of the first multiplexing means into STM frames of a synchronous digital hierarchy.

Claim 21

The interface according to claim 15, further comprising a second multiplexing means for multiplexing the output signals of the first multiplexing means into STM frames of a synchronous digital hierarchy.

Claim 24

The method claim 20, wherein:said high nominal bit rate is 140 or 155 Mbits/s and said separate lower-speed transmission signals each have a bit rate of about 1.5, 2, 6 or 8 Mbits/s.

Claim 25

A user-network interface in a digital transmission network for a cell-based digital signal comprising cells of fixed length and having a high nominal bit rate, said interface comprising: an input buffer means for receiving and buffering the cell-based signal; a policing means for controlling said buffer means to adapt the rate of the received cell-based signal to the actual transmission speed of the transmission network; a mapping means for forming cell blocks of N consecutive cells from the cell-based signal and for adding N overhead bytes to each cell block; a first multiplexing means for multiplexing the output signal of the mapping means byte by byte into N separate output signals of about 1.5 Mbit/s, 2 Mbit/s, 6 Mbit/s or 8 Mbit/s, N being integer higher than 1; a first generator means for generating empty cells; a second generator means for generating control cells; and a combiner means for combining cells from the first and the second generator means with the rate-adapted cell-based signal before applying the signal to the mapping means.

Claim 26

A user-network interface in a digital transmission network for a cell-based digital signal comprising cells of fixed length and having a high nominal bit rate, said interface comprising: an input buffer means for receiving and buffering the cell-based signal; a policing means for controlling said buffer means to adapt the rate of the received cell-based signal to the actual transmission speed of the transmission network; a mapping means for forming cell blocks of N consecutive cells from the cell-based signal and for adding N overhead bytes to each cell block; a first multiplexing means for multiplexing the output signal of the mapping means byte by byte into N separate output signals of about 1.5 Mbit/s, 2 Mbit/s, 6 Mbit/s or 8 Mbit/s, N being integer higher than 1; a first generator means for generating empty cells; a second generator means for generating control cells; and a combiner means for combining cells from the first and the second generator means with the rate-adapted cell-based signal before applying the signal to the mapping means.