The Evolution of NFV

• From closed, propriety, vertical to standard, commodity, horizontal hardware/software/platform.
• Greatly reduce CAPEX and OPEX for telecom operators.
• A new business model of virtualized, modularized, and customized micro-services (network slices).

Network Service Slice

• Slice 1 – Enhanced Mobile Broadband network slice:
  CDN (Content Delivery Networking), ICN (Information Concentric Networking)
• Slice 2 – Ultra Reliable Low Latency Communications network slice:
  IoV (Internet of Vehicles), V2V (Vehicle to Vehicle), V2I (Vehicle to infrastructure), V2X (Vehicle to anything)
• Slice 3 – Massive Machine Type Communications network slice:
  IoT (Internet of Things)

The Evolution of Radio Access Network

1G/2G RAN: RRH/BBU collocated

Existing issues:

• Base station must be located beside the antenna because of the rapid signal attenuation of coax cable.
• Huge expense on air condition system for the base stations deployed outdoor.
• Low utilization of base station resources.
• Base stations are difficult to communicate with each other via X2 interface.

Solved issues:

• Improve flexibility of deployment since theremote radio head function split from baseband unit.
• Indoor BBU deployment can reduce air conditioning cost.

Existing issues:

• Low utilization of base station resources.
• Base stations are difficult to communicate with each other via X2 interface.

Additional issues:

• Require low latency and accurate synchronization on Ir interface.

4G/B4G RAN: vBBU/RRH fixed function split

Solved issues:

• Virtualized BBU pool deployed on a single hardware can reduce cost and increase resource utilization.
• Save energy by reducing BBU hardware.
• Centralized BBU pool makes base stations cooperate much easier.

Existing issues:

• Require low latency and accurate synchronization on Ir interface.

Extra issues:

• Require higher backhaul bandwidth on S1 interface.

The Next Generation RAN

Separate RAN into three units: CU, DU, and RU that make your deployment more flexible.

• RU: The radio unit that handles RF and Low-PHY layer. The main considerations of RU design are size, weight and power consumption.
• DU: The distributed unit handles High-PHY, MACand RLC layers. This node runs a part of gNB functions depending on the functional split option, and controlled by the CU.
• CU: The centralized unit that handles PDCP and RRC layers.

The purposes of separating DU from RU:

• Less intelligent RU costs less
• The ability to control multiple RUs simultaneouslyto enable base station cooperation features like CoMP.
• Sharing baseband resource

The Evolution of Core Network

4G Core Network: EPC (Evolved Packet Core)

• Dedicated hardware and software for each network function.
• Point-to-Point interfaces between network functions.
• C/U plane are not completely separated.
• High expense and difficult to maintain, upgrade, recover, or add new services for operators.

5G Core Network

• Virtualized and modularized network functions on standard x86 servers.
• Service-Based Interface instead of Point-to-Point.
• Fully separated C/U plane.
• Lower expense and easier to maintain, upgrade, recover, or add new services for customized network slicefor operators.

Multi-access Edge Computing

• Highly reduce latency of RAN.
• Highly save the bandwidth from core network to Internet.
• Perform as a pivotal control/data/information node in between RANs and CNs or even the Internet clouds.

Performance Optimization

• Specialized accelerators based on FPGA (or eASIC) and ASICs for offloading CPU on compute intensive FEC / LDPC tasks.
• Lowering hardware requirement for DU allowing lower CAPEX and reducing energy requirement for lower OPEX

Summary

• 5G is based on years of evolution in wireless technologies.
• Introducing the possibility of using general purpose equipment as feasible alternative to expensive ASIC based proprietary solutions.
• Lowering the hurdle for 5G deployment as well as making it possible for private entities to deploy their own private 5G networks.