Journey to 5G adoption: Key network transformation areas

Journey to 5G adoption: Key network transformation areas 
Adoption of 5G is one of the major focus areas of most global Telco providers currently with hopes of
 utilizing 5G to provide many new services to users & creating new 
revenue streams. In order to achieve the same Telcos have been on a 
network transformation journey from last 4–5years by initially focusing 
on virtualizing their Infrastructure & Network Elements & then 
on moving network to the cloud by adopting cloud technologies. However, 
based on where the operator is located,the regulatory norms and 
technology adoption status in the region and their financial health, the
 operators are in different phases of the transformation.
While transformation is essentially never ending, in this article we will be briefly looking into the key areas of network transformation that network operators need to focus on as part of their 5G adoption roadmap to realize maximum benefits of 5G.
Key focus areas to consider as part of Network Transformation for maximum 5G benefitsFor
 the 5G Network to be most efficient the design should ensure that it’s 
“Agile to the core” and to achieve this the target should be to build 5G
 network on a network cloud, using “Open” architecture, leveraging 
disruptive technologies like AI/ML/Cloud & having automation built 
in.
Below are some key focus areas that should be considered as they are either essential for 5G or recommended :
1. Adopting Cloud Technologies:5G
 has been designed incorporating Cloud infrastructure as its foundation 
& in order to see the true potential, its essential cloud 
technologies are adopted throughout the network. Depending on the 
workloads/use case & the expected amount of traffic decision can be 
taken on the type of cloud setup required (private/public/hybrid) and 
the service type to be utilized on each cloud (IaaS/PaaS/SaaS).
Adoption
 of cloud technologies, will also help the Telcos to better manage the 
data center traffic, associated CAPEX & OPEX costs & provide 
additional avenues for Data redundancy ( subject to regulations).
2. Containers based Microservices Architecture:Microservices
 is one of the big developments of last decade which has changed the way
 applications are built, packaged & ultimately deployed by 
decomposing the monolithic application into services modules where each 
service is a functionality that is performed by the application. 
Microservices implementation has enabled service modules to be developed
 independently and in parallel to each other making the development 
cycle more agile and enabling faster turn around time for the 
application. Also as each service is independent, each service is 
deploy-able independently as per continuous deployment methodology &
 scaled as well independently as and when required.
With
 software becoming independent since introduction of virtualization 
& containerization in Telecom, the microservices based architecture 
has become the requirement for application/software which are part of 
Telecom architecture. Additionally, with cloud & cloud technologies 
serving as base for 5G(including some 4G implementations) and all latest
 telecom technologies, containerized versions of applications/software 
has become necessity to be able to utilize the benefits provided by 
cloud computing & to be able to utilize the portability benefit 
provided by containers in Telcos Hybrid Cloud Setup.
3. OSS/BSS Modernization:Modernization
 of BSS (Business Support System) & OSS (Operations Support System) 
is not something new to 5G. However, it is a crucial from perspective of
 5G benefits realization.
As
 per the points we have discussed above, the BSS/OSS systems should 
undergo digital transformation such that in the end it is essentially 
running on cloud, having microservices based implementation deployed as 
containers & leveraging automation & orchestration in its entire
 setup where ever possible along with Artificial Intelligence & 
Machine Learning capabilities in order to achieve close to perfect “Zero
 Touch Provisioning”. Also, to further ensure OSS/BSS is having “Open” 
architecture the systems should be compliant to TMForum standard 
specified interfaces and OpenAPIs.
From
 5G perspective, The dream scenario would be for the entire use 
case/service order journey till activation to take place with a click of
 a button. Eg: If telco’s customer wants an IoT service then:
Order would be fed manually into the CPQ software (Configure, Price, Quote).
The
 CPQ would interface with the BSS systems (Product/Service Catalog, 
CRM(Customer Relationship Manager)) to check available catalog options, 
getting/updating customer data and provide pricing to customer.
The sales agent would accept the price or make any necessary correction and submit the order.
Once
 order is submitted then order would go to order system, update 
inventory systems and then service design should takes place where 
service order is decomposed into workflow tasks.
The
 workflow tasks are executed by service/network provisioning and finally
 orchestration & activation for both IoT device as well as the IoT 
service on 5G Core (including 5G slice selection if setup) through 
domain/service orchestrator like MANO.
Once
 service is active intimation is sent to Billing systems to bill usage 
to customer & customer notified of service readiness.
Also
 service monitoring & fault management tasks take place and in case 
of any issues detected by assurance system automatically closed loop 
assurance will get triggered to the MANO system and the network elements
 as applicable.
In
 entire journey in above dream scenario user involvement is mainly 
towards order time & nothing else. But in a practical scenario as 
well user involvement can be made minimal with proper network 
architecture design & digital BSS/OSS system described above.
The below figure shows the BSS/OSS systems and their connectivity from end to end perspective. of BSS/OSS cycle .

4. End to End Network Service OrchestratorAs
 operators started transforming their networks to include virtualization
 and containerization, they have started adopting different 
MANO(Management & Orchestration) solutions to orchestrate and mange 
lifecycle of Network functions (Virtual or Containerized). However, the 
setup is are more geared towards VNFM(VNF Managers) provided by specific
 vendors and VIM(Virtual Infrastructure Manager) provided by the 
virtualizing platform/Kubernetes. Also, involvement of NFVO(NFV 
Orchestrator) & G-VNFM (Generic- VNFM) is in limited capacity only 
within the scope of select network elements or use cases. The ETSI NFV 
architecture showing the MANO components can be seen in the image.

To
 make 5G efficient, in order to automate & orchestrate majority 
tasks with minimal user intervention, the operators should have an End 
to End Network Service Orchestrator that would handle requests from BSS 
OSS and manage the same by orchestrating request through existing 
orchestrators & overall end to end managing lifecycle of the 5g 
network/use case. Also the end to end orchestrator could as well serve 
as domain/service orchestrator if required, assist with closed loop 
automation & manage lifecycle of individual network functions if 
required.
Below image showcases end to end orchestrator in an example.
Example:
 An operator has deployed 3 clouds — RAN, 5G Core & Edge and looking
 to deliver 5G service and Edge service. Their Edge service 
implementation involves selection of the 5G core elements from 5G core 
cloud and integrating with Edge Network functions present on the Edge 
cloud.
For
 this scenario orchestration & lifecycle management, the operator 
has following orchestrators: (i) 3 VIMs — to manage the 3 infra cloud 
platforms (ii) 2 VNFM — to manage RAN & 5G Core/Edge (iii) 3 NFVO — 
to orchestrate & setup RAN xNFs, 5G Core xNFs & 5G/Edge service 
(iv) 1 End to End Network Service Orchestrator — which would receive 
request from SOM or Service fulfillment and automate orchestration 
through relevant NFVO/VNFM & appropriate VIM. Also the orchestrator 
would coordinate with assurance for any close loop assurance aspects.
5. ORAN implementation:In
 the points covered so far, we have focused more on telecom systems 
perspective on which 5G technology would run rather than 5G technology 
network elements/architecture perspective. In this point we are looking 
at 1 of the core elements of 5G technology i.e. Radio Access Network 
(RAN). RAN along with 5G core & application servers plays a major 
part from 5G Network realization perspective.
Open
 RAN (ORAN) is essentially Cloud RAN / virtualized RAN implementation 
with “Open” interfaces. With goal of 5G network to be “Open” in a cloud 
platform, Open Cloud RAN is the obvious choice of implementation to 
achieve the same. Operators are already slowly migrating from 
traditional cell sites to deploying virtualized/cloud RAN solution and 
Open RAN timing essentially couldn’t be better as it saves the operators
 from investing too much on first migrating to vRAN/cloud RAN and then 
to ORAN. Also in case operator has migrated to vRAN solution 
implementing of ORAN will not be a big challenge as it mainly would 
involve deploying new xNF for Radio Unit(RU),Distributed Unit(DU) & 
Control Unit(CU) which support “Open” interfaces from ORAN offering of 
vendors.
Additionally,
 OpenRAN architecture has introduced a component for orchestration 
aspects, management and automation of RAN elements called SMO (Service 
Management & Orchestration). SMO’s role will be vital when 5G use 
cases involving Network Slicing are needed and their orchestration / 
management is required.
The
 SMO can be integrated with an E2E network service orchestrator(as 
mentioned in point 3) to automate the overall request process from 
BSS/OSS.
The ORAN architecture from ORAN Alliance is shown in image below.

ORAN Architecture6. Service Based Architecture 5G Core:The
 last key focus area is another core aspect of 5G Technology i.e. 5G 
core. 5G Core will be dealing with both data/voice user plane traffic as
 well as control plane traffic and working along with RAN for 5G 
connectivity & application servers for use cases realization.
Operators need to implement the 5G core which uses Service based architecture and defined by ETSI TS 123 501
 . The 5G core involves separation of Control & User Plane functions
 based on services being implemented (essentially decomposing into 
microservices) and making it more modular . This implementation permits 
placing Control functions at more centralized locations while User plane
 functions at individual data center/cloud locations.Also, this architecture enables supporting of Network Slicing use cases 
to allot portion of Packet core for use in IoT or Edge or any other 5G 
use cases as required.
The 5G architecture is shown below:

5G Core ArchitectureThe
 network functions part of 5G core are: Authentication Server Function 
(AUSF) ; Access and Mobility Management Function (AMF) ; Data Network 
(DN) e.g. operator services, Internet access or 3rd party services ; 
Unstructured Data Storage Function (UDSF) ; Network Exposure Function 
(NEF) ; Network Repository Function (NRF) ; Network Slice Specific 
Authentication and Authorization Function (NSSAAF) ; Network Slice 
Selection Function (NSSF) ; Policy Control Function (PCF) ; Session 
Management Function (SMF) ; Unified Data Management (UDM) ; Unified Data
 Repository (UDR) ; User Plane Function (UPF) ; UE radio Capability 
Management Function (UCMF) ; Application Function (AF) ; User Equipment 
(UE) ; (Radio) Access Network ((R)AN) ; 5G-Equipment Identity Register 
(5G-EIR) ; Network Data Analytics Function (NWDAF) ; CHarging Function 
(CHF).
ConclusionWhile
 change is only constant in transformation & there are alternatives 
to keep the ball rolling for operators, above points if adopted position
 operators in best possible way for taking advantage of 5G & forward
 looking into realizing 6G, 7G & so on…
Disclaimer:
 The post above expresses my sole viewpoint and not the opinion of any 
organization I work with presently or in the past.