A transmission apparatus, comprising: - N Ethernet Medium Access Control MAC ports (RS101-1,..., RS101-N), wherein each Ethernet MAC port is corresponding to a first Medium Independent Interface MII interface, - K Ethernet physical layer interfaces (103-1,..., 103-K), wherein each Ethernet physical layer interface is corresponding to a second MII interface, wherein both N and K are positive integers, N>1, and K>1; and - a connection device, wherein the transmission apparatus is characterized in that it has a set of features A or a set of features B, the set of features A being defined as consisting of - the connection device being configured to control a time-division interconnect bus in the connection device to implement a connection between a timeslot of the first MII interface and a timeslot of the second MII interface, - the N Ethernet MAC ports (RS101-1,..., RS101-N) being adapted to be separately connected to the time-division interconnect bus in the connection device by using the corresponding first MII interfaces, and - the K Ethernet physical layer interfaces (103-1,..., 103-K) being adapted to be separately connected to the time-division interconnect bus in the connection device by using the corresponding second MII interfaces; the set of features B being defined as consisting of - the connection device being configured to control a time division space division switching matrix in the connection device to implement a connection between a timeslot of the first MII interface and a timeslot of the second MII interface, - the N Ethernet MAC ports (RS101-1,..., RS101-N) being adapted to be separately connected to the time-division space-division switching matrix in the connection device by using the corresponding first MII interfaces, and - the K Ethernet physical layer interfaces (103-1,..., 103-K) being adapted to be separately connected to the time-division space-division switching matrix in the connection device by using the corresponding second MII interfaces; and in that the first MII interfaces that correspond to any two different Ethernet MAC ports differ; wherein the second MII interfaces that correspond to any two different Ethernet physical layer interfaces differ. - N Ethernet Medium Access Control MAC ports (RS101-1,..., RS101-N), wherein each Ethernet MAC port is corresponding to a first Medium Independent Interface MII interface, - K Ethernet physical layer interfaces (103-1,..., 103-K), wherein each Ethernet physical layer interface is corresponding to a second MII interface, wherein both N and K are positive integers, N>1, and K>1; and - a connection device, wherein the transmission apparatus is characterized in that it has a set of features A or a set of features B, the set of features A being defined as consisting of - the connection device being configured to control a time-division interconnect bus in the connection device to implement a connection between a timeslot of the first MII interface and a timeslot of the second MII interface, - the N Ethernet MAC ports (RS101-1,..., RS101-N) being adapted to be separately connected to the time-division interconnect bus in the connection device by using the corresponding first MII interfaces, and - the K Ethernet physical layer interfaces (103-1,..., 103-K) being adapted to be separately connected to the time-division interconnect bus in the connection device by using the corresponding second MII interfaces; the set of features B being defined as consisting of - the connection device being configured to control a time division space division switching matrix in the connection device to implement a connection between a timeslot of the first MII interface and a timeslot of the second MII interface, - the N Ethernet MAC ports (RS101-1,..., RS101-N) being adapted to be separately connected to the time-division space-division switching matrix in the connection device by using the corresponding first MII interfaces, and - the K Ethernet physical layer interfaces (103-1,..., 103-K) being adapted to be separately connected to the time-division space-division switching matrix in the connection device by using the corresponding second MII interfaces; and in that the first MII interfaces that correspond to any two different Ethernet MAC ports differ; wherein the second MII interfaces that correspond to any two different Ethernet physical layer interfaces differ.