BL0-220 Sample Questions Answers

Multitenancy in cloud computing defines a set of cloud resources shared by several customers. Multitenancy is a feature of cloud computing that allows multiple customers, or tenants, to use the same cloud infrastructure and services, such as servers, storage, network, and applications, while maintaining their own data and configuration. Multitenancy enables cloud providers to optimize the utilization and allocation of cloud resources, reduce the cost and complexity of cloud operations, and offer scalable and flexible services to different customers. Multitenancy also benefits customers by providing them with on-demand access to cloud resources, pay-per-use pricing models, and enhanced security and isolation. The other options are not correct definitions of multitenancy in cloud computing. A set of cloud resources isolated from each other is a single-tenant model, where each customer has its own dedicated cloud infrastructure and services. A set of cloud resources located in different data centers is a distributed cloud model, where cloud resources are spread across multiple physical locations to provide low latency, high availability, and local compliance. A set of cloud resources assigned to the same network slice is a network slicing model, where a logical network is created over a sharedphysical network to support specific applications and customers with customized performance, quality, and security. References: Nokia Bell Labs 5G Professional Certification - Distributed Cloud Networks, Unit 2: Cloud Technologies and Features, Section 2.2: Cloud Characteristics.

The most appropriate word to complete the sentence is benefits. The public cloud ecosystem offers many benefits to users, such as scalability, flexibility, cost-efficiency, and innovation12. Constraints, problems, and operability are not suitable words to describe the advantages of the public cloud ecosystem over the simple consumption of resources. References: 1: Nokia Bell Labs Distributed Cloud Networks, Unit 1: Cloud Ecosystem, slide 7 2: Nokia Bell Labs 5G Certification Program - Blended Learning, Section 2: Distributed Cloud Networks, slide 9

Adaptability is the most critical benefit a cloud native deployment provides when deploying applications in complex and very low predictive environments. Cloud native applications are designed to be modular, scalable, resilient, and portable across different cloud platforms1. They can leverage the cloud features such as automation, orchestration, and service discovery to dynamically adjust to changing conditions and demands2. This enables them to cope with the complexity and unpredictability of the environments they operate in, such as edge computing, industrial automation, and smart cities3. Capability and reliability are also important benefits of cloud native deployment, but they are not the most critical ones. Capability refers to the ability to deliver high-performance and feature-rich applications that meet the user and businessneeds1. Reliability refers to the ability to ensure the availability and consistency of the applications despite failures or errors1. However, these benefits are not sufficient if the applications cannot adapt to the evolving and diverse scenarios they face in the real world. References: 1: Nokia Bell Labs Distributed Cloud Networks, Unit 2: Cloud Technologies and Features, Section 2.3: Cloud Native applications design 2: Nokia Bell Labs Distributed Cloud Networks, Unit 2: Cloud Technologies and Features, Section 2.5: Microservices and Containerization 3: Google Cloud, Nokia partner to accelerate cloud-native 5G3

Habana and EyeQ are two examples of AI hardware solutions that are designed to accelerate deep learning and computer vision applications. Habana is a company that produces AI processors for both training and inference workloads1. EyeQ is a family of system-on-chips (SoCs) developed by Mobileye for advanced driver-assistance systems (ADAS) and autonomous driving2. DataLake and Sparks are not AI hardware solutions. DataLake is a term that refers to a large-scale data storage architecture that can store structured, semi-structured, and unstructured data from various sources3. Sparks is a misspelling of Spark, which is an open-source distributed computing framework for large-scale data processing and machine learning4. References: 1: Nokia Bell Labs Distributed Cloud Networks, Unit 4: AI/ML in Cloud Networks, Section 4.2: AI Hardware 2: Nokia Bell Labs Distributed Cloud Networks, Unit 4: AI/ML in Cloud Networks, Section 4.2: AI Hardware 3: Nokia Bell Labs Distributed Cloud Networks, Unit 2: Cloud Technologies and Features, Section 2.4: Cloud Storage 4: Nokia Bell Labs Distributed Cloud Networks, Unit 4: AI/ML in Cloud Networks, Section 4.3: AI Software

A Network Service Descriptor (NSD) is a template that defines the characteristics and requirements of a network service, such as the number and type of virtual network functions (VNFs), the connectivity and topology between them, the scaling policies, and the service level agreements1. A NSD is defined in a catalog that is managed by the cloud orchestration layer, which is responsible for deploying, monitoring, and controlling the network services across the distributed cloud2. Therefore, cloud orchestration requires a NSD defined in a catalog, while the other options do not. References: 1: Nokia Bell Labs Distributed Cloud Networks, Unit 3: Cloud Resource Planning, Topic: Network Service Descriptor Role 2: Nokia Bell Labs Distributed Cloud Networks, Unit 4: Operating Your Cloud, Topic: Cloud Orchestration

A Network Service Descriptor (NSD) is an integral part of network function virtualization (NFV) architecture. It describes the composition of network services, including how different network functions are chained or combined to provide a specific service. Cloud orchestration involves the automated management of various cloud computing services and resources, including networking services. It requires a comprehensive description of these services (i.e., NSD) to automate their deployment, scaling, and management effectively. NSD in a catalog would be used to define the parameters and configurations needed for the orchestrated service to be deployed in a cloud environment, making cloud orchestration the most likely context for requiring an NSD.

To reduce time and complexity for development and deployment. Comprehensive Explanation and References of Correct Answer: The main advantage of development concepts such as DevOps and CI/CD used in cloud native applications is to reduce time and complexity for development and deployment. DevOps is a set of practices that aims to improve collaboration and communication between development and operations teams, and to automate and streamline the software delivery process. CI/CD is a subset of DevOps that focuses on continuous integration, continuous delivery, and continuous testing of software changes. By using these concepts, cloud native applications canachieve faster and more frequent releases, higher quality and reliability, lower costs and risks, and better customer satisfaction.

References:

• Nokia Bell Labs 5G Professional Certification - Distributed Cloud Networks, Unit 4: Operating Your Cloud, slide 3
• Catching the 5G train with CI/CD Services, paragraph 1
• Nokia unveils new 5G core deployment services to give operators better capabilities, paragraph 1

Software as a Service (SaaS) is a cloud computing offering that provides users with access to a vendor's cloud-based software. Users do not install applications on their local devices. Instead, the applications reside on a remote cloud network accessed through the web or an API. Within this context, Database-as-a-Service (DBaaS) is considered a form of SaaS, where the service provider manages the database's installation, maintenance, backup, and scaling needs on behalf of the customer. Platform-as-a-Service (PaaS) provides a platform allowing customers to develop, run, and manage applications without dealing with the complexity of building and maintaining the infrastructure typically associated with developing and launching an app. PaaS can include various software components, including database management systems, and thus can be considered a subset of SaaS.

Latency, Privacy and Capacity are the three key drivers required for video-based service in on-premise cloud. Latency refers to the delay between the source and the destination of a video stream, which affects the quality of experience for the end-users. Privacy refers to the protection of the video content and the user data from unauthorized access or leakage. Capacity refers to the ability of the network and the cloud to handle the high bandwidth and storage demands of video applications. On-premise cloud is a cloud deployment model where the cloud infrastructure is located within the enterprise premises, and is managed by the enterprise or a third-party service provider. On-premise cloud can offer lower latency, higher privacy and greater capacity for video-based service than public cloud, which is located outside the enterprise premises and is shared by multiple tenants. References: Nokia Bell Labs 5G Professional Certification - Distributed Cloud Networks, Unit 2: Cloud Technologies and Features, Section 2.3: Cloud Deployment Models.

 The 5G Core control plane is responsible for managing the network functions, services, and resources, such as authentication, authorization, session management, policy control, mobility management, etc.1. The 5G Core control plane can be deployed in a distributed cloud architecture, which consists of different cloud layers that have different characteristics and roles2. The Metro Edge Cloud is a cloud layer that is located near the access network, and provides low latency, high bandwidth, and local processing for the control plane functions3. The Core/Central Cloud is a cloud layer that is located in the core network, and provides high availability, scalability, and security for the control plane functions4. The distributed cloud architecture enables the 5G Core control plane to optimize the network performance, efficiency, and flexibility, and to support various use cases and applications. References: 1: Nokia Bell Labs Distributed Cloud Networks, Unit 1: Cloud Ecosystem, Section 1.2: Cloud Architecture 2: Nokia Bell Labs Distributed Cloud Networks, Unit 1: Cloud Ecosystem, Section 1.3: Distributed Cloud 3: Nokia Bell Labs Distributed Cloud Networks, Unit 3: Cloud Resource Planning, Section 3.2: Cloud Resource Planning for Distributed Cloud 4: Nokia Bell Labs Distributed Cloud Networks, Unit 3: Cloud Resource Planning, Section 3.3: Cloud Resource Planning for Central Cloud : Nokia Bell Labs Distributed Cloud Networks, Unit 5: New Services Automation, Section 5.1: Distributed Cloud Services Automation

Monolithic applications are a mono-block functional service because they are composed of a single, self-contained unit that contains all the components of the application, such as the user interface, business logic, data access, etc1. Monolithic applications are not smaller in size than cloud native applications, as they tend to grow larger and more complex over time2. Monolithic applications are not more reliable than microservices, as they are more prone to failures, bugs, and performance issues due to the tight coupling and interdependency of the components3. Monolithic applications do not involve the most complex management strategy, as they are easier to develop, test, and deploy initially, but they become harder to maintain, scale, and update as the application evolves4. References: 1: Nokia Bell Labs Distributed Cloud Networks, Unit 2: Cloud Technologies and Features, Section 2.4: Cloud Application Architectures 2: Monolithic Architecture 3: Microservices vs Monolithic Architecture 4: Monolithic vs. Microservices Architecture

The statement that best describes the scaling stage of the application life cycle is the application adjusts its capacity. Scaling is the process of increasing or decreasing the number of resources allocated to an application based on the demand and performance1. Scaling can be done manually or automatically using policies and metrics1. The other statements do not describe the scaling stage, but rather other stages of the application life cycle. The periodic upgrade of the service is part of the maintenance stage, which ensures the reliability and security of the application2. The deployment of the application over the infrastructure is part of the installation stage, which involves the configuration and activation of the application2. The termination and freeing of associated resources is part of the decommissioning stage, which removes the application from the network2. References: 1: Nokia Bell Labs Distributed Cloud Networks, Unit 4: Operating Your Cloud, slide 23 2: Nokia Bell Labs Distributed Cloud Networks, Unit 4: Operating Your Cloud, slide 10

A YAML XML template file contains the configuration of a VNF or CNF. A VNF stands for Virtual Network Function, which is a software-based network function that runs on a virtual machine or a container. A CNF stands for Cloud-native Network Function, which is a network function that is designed and implemented using cloud-native principles and technologies, such as microservices, containers, and Kubernetes. A YAML XML template file is a file that defines the structure, parameters, and dependencies of a VNF or CNF, as well as the resources and policies required to deploy and manage it. A YAML XML template file is based on the TOSCA (Topology and Orchestration Specification for Cloud Applications) standard, which is a language for describing the components and relationships of complex cloud applications. A YAML XML template file is used by the MANO (Management and Orchestration) system to instantiate, configure, and operate a VNF or CNF on the cloud infrastructure. References: Nokia Bell Labs 5G Professional Certification - Distributed Cloud Networks, Unit 2: Cloud Technologies and Features, Section 2.4: Cloud Software and Hardware Resources.

 On-Boarding of a Network Service requires both NS and NF templates. NS stands for Network Service, which is a logical grouping of network functions and resources that provide a specific functionality or service to the end user. NF stands for Network Function, which is a software component that performs a specific task or function within the network. Templates are files that describe the characteristics, requirements, and dependencies of network services and network functions. On-Boarding is the process of registering and validating network services and network functions in the cloud platform, so that they can be instantiated and managed.

References:

• Nokia Bell Labs 5G Professional Certification - Distributed Cloud Networks, Unit 5: New Services Automation, slide 7
• Module by Module - Self Study Note Guide, DC5.1– New Services Automation, page 19

On-boarding a Network Service typically involves Network Service (NS) and Network Function (NF) templates. NS templates define the overall structure and requirements of a network service, including its composition of various NFs and their interconnections. NF templates specify the configurations for individual network functions that are part of the service. Together, they enable the automated deployment and management of complex network services in a standardized manner.

All life cycle stages are clearly identified. Comprehensive Explanation and References of Correct Answer: Life cycle management is the process of managing the development, deployment, operation, and decommissioning of cloud applications and services. It involves defining the requirements, design, testing, deployment, monitoring, scaling, updating, and retiring of cloud resources. One of the benefits of life cycle management is that it provides clarity and visibility into the different stages of the cloud service, from inception to termination. This helps to ensure quality, efficiency, security, and reliability of the cloud service, as well as to optimize the use of resources and reduce costs.

References:

• Nokia Bell Labs 5G Professional Certification - Distributed Cloud Networks, Unit 4: Operating Your Cloud, slide 3
• Module by Module - Self Study Note Guide, DC4.1– Industry Trends in Data Center Hardware, page 16

The networking concept of “Underlay” refers to the physical network layer that provides the connectivity and transport for the overlay network, which is the virtual network layer that runs on top of the underlay network1. The underlay network is composed of routers, switches, links, and protocols that enable the data transmission between different locations2. The underlay network is independent of the overlay network, meaning that it does not need to be aware of the network configuration, policies, or services of the overlay network3. Therefore, option A best describes the underlay network, while options B, C, and D are incorrect. References: 1: Nokia Bell Labs Distributed Cloud Networks, Unit 2: Cloud Technologies and Features, Topic: Underlay and Overlay Networks 2: Module by Module - Self Study Note Guide, DC2.2– Cloud Options 3: Underlay Network - an overview | ScienceDirect Topics, Overview