FIBRE-OPTIC CROSS-CONNECTION SYSTEM

Abstract

The invention relates to a fibre-optic cross-connection system; in particular having spine-leaf topology, having an input side (S1, S2), in particular a spine side, which has one or a plurality (n) of input switches (S1, S2), Each input switch (S1, S2) comprises a plurality of fibre-optic multi-channel transceivers (QSFP S1.1-S1.4; QSFP S2.1-S2.4), each of which has a number of k fibre-optic channels (Tx0-Tx3). The fibre-optic cross-connection system also has an output side (L1-L4); in particular a leaf side, which has a plurality (m) of output switches (L1, L2, L3, L4) which each have a plurality of fibre-optic multi-channel transceivers (QSFP L1.1-L1.2; QSFP L2.1-L2.2; QSFP L3.1-L3.2; QSFP L4.1-L4.2). The fibre-optic channels (Tx0-Tx3) of at least one, in particular every, input-side multi-channel transceiver (QSFP S1.1-S1.4; QSFP S2.1-S2.4) are divided and connected to output-side multi-channel transceivers (QSFP L1.1-L1.2; QSFP L2.1-L2.2; QSFP L3.1-L3.2; QSFP L4.1-L4.2) which are different from one another, in particular belonging to different output switches (L1, L2, L3, L4).

Claims

1. A fibre-optic cross-connection system, in particular having spine-leaf topology, having: an input side (S1, S2), in particular a spine side, which has one or a plurality (n) of input switches (S1, S2), each input switch (S1, S2) comprising a plurality of fibre-optic multi-channel transceivers (QSFP S1.1-S1.4; QSFP S2.1-S2.4), each of which has a number of k fibre-optic channels (Tx0-Tx3), and an output side (L1-L4), in particular a leaf side, which has a plurality (m) of output switches (L1, L2, L3, L4) which each have a plurality of fibre-optic multi-channel transceivers (QSFP L1.1-L1.2; QSFP L2.1-L2.2; QSFP L3.1-L3.2; QSFP L4.1-L4.2), wherein the fibre-optic channels (Tx0-Tx3) of at least one, in particular every, input-side multi-channel transceiver (QSFP S1.1-S1.4; QSFP S2.1-S2.4) are divided and connected to output-side multi-channel transceivers (QSFP L1.1-L1.2; QSFP L2.1-L2.2; QSFP L3.1-L3.2; QSFP L4.1-L4.2) which are different from one another, in particular belonging to different output switches (L1, L2, L3, L4).

2. The fibre-optic cross-connection system according to claim 1, wherein the connections of the input-side and/or output-side multi-channel transceivers (QSFP S1.1-S1.4; QSFP S2.1-S2.4; QSFP L1.1-L1.2; QSFP L2.1-L2.2; QSFP L3.1-L3.2; QSFP L4.1-L4.2) are plug-in connections.

3. The fibre-optic cross-connection system according to claim 1, wherein the at least one or the plurality (n) of input switch(es) (S1, S2) is/are connected to the plurality (m) of output switches (L1-L4) by means of a connection device (1).

4. The fibre-optic cross-connection system according to claim 3, wherein the connection device (1) has a number of k channel inputs for each connected input-side multi-channel transceiver (QSFP S1.1-S1.4; QSFP S2.1-S2.4), k designating the number of fibre-optic channels of each input-side multi-channel transceiver (QSFP S1.1-S1.4; QSFP S2.1-S2.4).

5. The fibre-optic cross-connection system according to claim 3, wherein the connection device (1) has a number of k channel outputs for each connected output-side multi-channel transceiver (QSFP L1.1-L1.2; QSFP L2.1-L2.2; QSFP L3.1-L3.2; QSFP L4.1-L4.2), k designating the number of fibre-optic channels of each input-side multi-channel transceiver (QSFP S1.1-S1.4; QSFP S2.1-S2.4) and/or output-side multi-channel transceiver (QSFP L1.1-L1.2; QSFP L2.1-L2.2; QSFP L3.1-L3.2; QSFP L4.1-L4.2).

6. The fibre-optic cross-connection system according to claim 4, wherein the channel inputs and/or channel outputs are provided in LC, ST or MPO plug holders.

7. The fibre-optic cross-connection system according to claim 1, wherein the total number N2 of input-side and output-side multi-channel transceivers is $N_2=2.Math.m\left(n+\left[\frac{n}{k}\right]\right).$

8. The fibre-optic cross-connection system according to claim 1, wherein the number of fibre-optic channels of each input-side and/or output-side multi-channel transceiver is as follows: k=4.

9. The fibre-optic cross-connection system according to claim 1, wherein for establishing an inherent redundancy, the total number N2 of input-side and output-side multi-channel transceivers is less than 4 mn and preferably more than or equal to $2.Math.m.Math.n+\left(n.Math..Math.\frac{m}{k}.Math.+m.Math..Math.\frac{n}{k}.Math.\right).$

10. A method for use of a fibre-optic cross-connection system, in particular having spine-leaf topology, having: an input side (S1, S2), in particular a spine side, which has one or a plurality (n) of input switches (S1, S2), each input switch (S1, S2) comprising a plurality of fibre-optic multi-channel transceivers (QSFP S1.1-S1.4; QSFP S2.1-S2.4), each of which has a number of k fibre-optic channels (Tx0-Tx3), and an output side (L1-L4), in particular a leaf side, which has a plurality (m) of output switches (L1, L2, L3, L4) which each have a plurality of fibre-optic multi-channel transceivers (QSFP L1.1-L1.2; QSFP L2.1-L2.2; QSFP L3.1-L3.2; QSFP L4.1-L4.2), wherein the fibre-optic channels (Tx0-Tx3) of at least one, in particular every, input-side multi-channel transceiver (QSFP S1.1-S1.4; QSFP S2.1-S2.4) are divided and connected to output-side multi-channel transceivers (QSFP L1.1-L1.2; QSFP L2.1-L2.2; QSFP L3.1-L3.2; QSFP L4.1-L4.2) which are different from one another, in particular belonging to different output switches (L1, L2, L3, L4), the method comprising the step of establishing an inherent redundancy in case of a failure of a multi-channel transceiver.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In the following, the invention will be explained in more detail on the basis of an embodiment on the basis of FIGS. 1-5. The embodiment shown in FIGS. 2-4 and discussed is intended only to demonstrate how a cross-connection according to the invention is intended to be set up. A person skilled in the art will recognise that the system can be equipped or escalated using as many switches or multi-channel transceivers as required.

[0033] FIG. 1 is a diagram of a conventional, fibre-optic cross-connection system for two spine switches to four leaf switches having redundant optical channels;

[0034] FIG. 2 is a diagram of a fibre-optic cross-connection system according to the invention for two spine switches to four leaf switches having inherent redundant channels;

[0035] FIG. 3 is a layout example for a first leaf-quad-block cross-connection system for the application of two spine switches to four leaf switches;

[0036] FIG. 4 is an exemplary layout diagram of an MPO12 plug-in connector for multi-channel transceivers; and

[0037] FIG. 5 is an exemplary diagram of the split connections according to the invention on the example of a QSFP multi-channel transceiver.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0038] As shown in FIG. 1, the conventional, redundant design, in which a substitute transceiver must be provided in order to create the redundancy, requires, e.g. for the depicted spine-leaf connection structure having two spine switches and four leaf switches, a total number of thirty-two multi-channel transceivers QSFP (e.g. QSFP28), each having, for example, four internal fibre-optic channels (Tx and Rx). If, for example, a 100 Gb/s transmission system is used, the four internal channels each transport 25 Gb/s and are conventionally aggregated to 100 Gb/s.

[0039] In order to compensate for the failure of a QSFP, the spine switches are each connected to two QSFPs.

[0040] By means of the cross-connection system proposed according to the invention, which in particular is designed as a plug-in connection system, the fibre-optic channels of the connected multi-channel transceivers QSFPx (x is a placeholder), as the example in FIG. 2 shows, are divided by means of the use of the internal split mode of the QSFPs, such that not all, but rather some of the internal channels of the QSFP are switched to the particular receiver apparatus. The division of the four channels of a QSFP is shown, by way of example, in FIG. 5.

[0041] By means of the fibre connections, in particular plug-in fibre connections, of the proposed plug-in connection system, which comprises a connection device 1 in FIG. 2 which connects the input switches (also referred to here as spine switches) to the output switches (also referred to as leaf switches), the data lines are once again mixed together or aggregated using the plug-in scheme shown in FIG. 3, such that the entire data transfer rate can be conveyed to the receiver apparatus.

[0042] The plug-in connection from FIG. 3 can be implemented, for example, by means of so-called LC quad-couplings which are used as a connection device in the shown example, it being possible to use, for example, MPO plug-in elements in order to couple the individual channels to the connection device, as shown here by way of example.

[0043] The layout of an MPO12 plug-in element is shown in FIG. 4. Using this standard layout, the four internal channels (Tx and Rx) of the connected QSFP are mixed by means of the system according to the invention and, as a result, create the desired inherent redundancy.

[0044] In the shown example application, this results in a reduction of 50% in the number of QSFP in the case of proportionally obtained redundancy of the data transfer rate. The calculated proportional redundancy of the data transfer rate increases in this exemplary constellation by means of the fibre-optic channel mixture from 0% to 50% for the leaf switches and from 0% to 75% for the spine switches, since the failure of a QSFP only affects the total data transfer rate by a corresponding proportion owing to the internal split mode.

[0045] Consequently, the proposed concept of the inherent redundancy allows a 100% redundancy solution to be developed. For this purpose, in the example application from FIG. 2, the number of multi-channel transceivers used on the spine side increases in each case to six QSFPs per spine and on the leaf side increases in each case to three QSFPs. By means of this constellation, a 100% redundancy is possible in the event of QSFP failure, since the crossed channels of the remaining multi-channel transceivers can be used in order to provide the 100 Gb/s data transfer rate.

[0046] As a result of this constellation, the number of multi-channel transceivers required is reduced to 75% of the number of a conventional connection system from FIG. 1.