# The 6G Ecosystem as Support for IoE and Private Networks: Vision, Requirements, and Challenges
## 4 The Requirements of 6G
These classes, respectively, provide extensive coverage and performance across diverse domains; ultrahigh rates with low latency, and high data density with ultra-reliability. These technologies enhance robust communication infrastructure, ensuring ultra-massive connectivity, extreme reliability, and connection continuity, enabling pervasively intelligent, reliable, scalable, flexible, adaptable, and secure terrestrial wireless. Hence, 6G systems require a cellular communication redesign that offers exceptional flexibility, surpassing the existing scope through three key strategies: (i) leveraging various sensing mechanisms, including artificial intelligence (AI), to comprehend diverse facets of the communication network and environment, (ii) improving or revolutionizing technology options, and (iii) achieving optimal resource utilization by considering real-world sensing capabilities alongside awareness. Quality, performance, and alignment with the specifications of 6G communication systems are evaluated by establishing key performance indicators (KPIs). These KPIs are currently in the process of formulation and finalization by entities like the ITU Telecommunication Standardization Sector (ITU-T) and various industry stakeholders. Although still under development, the existing literature points to several overarching areas often taken into account [66]:  
* _Data Rate and Capacity:_ associated with system throughput. Measures of how much data can be transferred within a given time interval, reflecting the high-speed, high-capacity, peak and experienced spectral efficiency, maximum channel bandwidth, traffic capacity per geographic coverage area, and connection density. Must be fulfilled at 95% of all user locations. QoS and QoE will manage trade-offs between data transmission capacity or spectral efficiency and other concurrent metrics like energy efficiency and service latency. * _Latency:_ Defines the end-to-end latency and jitter, aiming for ultra-low latency to enable delay-sensitive real-time applications. * _Reliability:_ Defined by the metric for the duration of uninterrupted operation of infrastructure, and related to the orchestration and management of networks, ensuring robust and dependable communication, especially for critical applications like remote surgery or autonomous vehicles. * _Energy Efficiency:_ Focus on reducing energy consumption to prolong device battery life and promote sustainability. * _Coverage:_ Ubiquitous mobile ultra-broadband will be available everywhere, extending connectivity to remote and underserved areas, potentially through satellite networks. * _Spectral Efficiency:_ Maximizing data transmission over limited frequency bands. * _Mobility Support:_ Seamless communication while moving at high speeds, such as in high-speed trains or vehicles. * _Connection Density:_ Accommodating a high, or even a massive, number of devices within a certain geographic area is important for the IoT. * _Security and Privacy:_ Implementing strong security procedures to protect users and data. * _Sustainability:_ Ensuring that 6G networks and devices are environmentally sustainable and minimize their ecological footprint. A 6G network requires a service-based end-to-end (E2E) architecture with key roles played by software-defined networking (SDN), network function virtualization (NFV), and network slicing. These technologies enhance network programmability, enabling the creation of multiple logical networks on a shared physical infrastructure. Anticipated benefits include higher data rates, improved spectral and energy efficiency, broader coverage, wide bandwidths, extremely high reliability, ultra-low latency, and dynamic QoS management across all network segments. Dynamic QoS management is crucial for flexible network resource utilization. However, common SDN implementations often statically provide required QoS through resource reservation based on predefined rules in forwarding engines, mapping packets into existing queues with assigned priorities [85; 86].