# A Vision of 6 th Generation of Fixed Networks (F6G): Challenges and Proposed Directions
## 5 Optical Switching: Key Challenges and Proposed Directions  
### Need for More Sophisticated Switches to Support the F6G Ecosystem  
Today's industrial networks are not capable of handling the requirements of the growing IoT ecosystem, which incorporates the communication between machines, robots and sensors, especially in the industrial sector. Low data rates, high latency, and limited connectivity are the main characteristics of currently deployed networks, and they have become bottlenecks as they limit industrial manufacturing quality and efficiency. Therefore, there is an urgent demand to provide more bandwidth, ultra-low latency, and higher connectivity in order to handle the industry's time-sensitive traffic flow for automated manufacturing and industrial practices [13]. To further understand the optical switching required for the F6G ecosystem, we summarize some key quantities as they were stated in the previous EU-funded HORIZON-CL4-2021-DIGITAL-EMERGING-01-06 call:  
* Reliable and low latency communication with guaranteed service quality for the digital transformation of industrial processes. * Reduced congestion in data communication when a multiplicity of applications competes for simultaneous delivery, thereby causing data loss or a delay in data delivery. * Reduced power consumption to some pico-Joule per bit through the broader use of optical networking technologies, interconnects, and integrated optical communication components. * Lowered barrier for the uptake of higher-performance communication technologies by reducing the cost of transmission interfaces to around 50 cents per Gigabit per second. These requirements are critical for the operation of F6G networks and services and, in our opinion, a large amount of research work needs to be performed in order to offer the targeted switching components. The currently available solutions for switching, especially for services of the industrial sector, are almost entirely based on electrical interconnects, using expensive copper cables, and electronic switches for the aggregation of non-time-sensitive traffic and point-to-point links for the time -sensitive traffic. In the following paragraph, we present the main switching challenges that need to be efficiently addressed in order to satisfy the aforementioned requirements. One technical challenge for the F6G ecosystem is to provide a unified solution that can meet the stringent latency requirements utilizing a P2 MP architecture for both time-sensitive and non-time-sensitive traffic. A second challenge from an economical point of view is to provide a networking solution that can satisfy the cost and power consumption requirements mentioned above, as the traffic demands are scaling with time and are becoming larger. A third challenge is to create consensus around this solution with other system vendors and 14.0 system operators and be able to enter the very competitive, and somewhat closed, market of optical communication for industrial networks. Finally, the last challenge is to handle the very high capacity, which ends up in an optical node and needs to be switched efficiently at its egress. A schematical illustration of the switching concept,  
Figure 33: Predictions of capacity times length product (in Pb/s-km) based on experimental studies. which can be developed to interconnect both the \"Things\" within a factory and between the different factories is shown in Figure 34. In this schematic, two different switches are considered, one that is employed to interconnect the various \"things\" among the various factory floors (OXC-IF) and another one that can switch the traffic to and from the different interconnected factories (OXC-XC). Of course, depending on the factory characteristics and its dimensions, e.g., number of floors and number of interconnected items, it is possible to consider only a single optical switch per factory unit.