BL0-220 Nokia Bell Labs Distributed Cloud Networks Exam Questions and Answers

Multi-tenancy network connectivity provides dedicated resources through network slicing. Network slicing is a technique that allows operators to create multiple logical networks over a shared physical infrastructure. Each network slice can have its own characteristics, such as bandwidth, latency, security, and quality of service, to meet the specific requirements of different applications and customers. Network slicing enables operators to offer customized and differentiated services to various tenants, such as enterprises, industries, and public sector organizations, while optimizing the utilization of network resources. Network slicing is one of the key features of 5G networks, as it supports the diverse and dynamic use cases of 5G, such as enhanced mobile broadband, massive machine-type communications, and ultra-reliable low-latency communications. References: Nokia Bell Labs 5G Professional Certification - Distributed Cloud Networks, Unit 4: Operating Your Cloud, Section 4.2: Network Slicing.

 Low latency is the primary benefit of an Edge Cloud. Edge Cloud is a distributed cloud architecture that brings cloud resources closer to the end users and devices, reducing thedistance and delay for data transmission1. Low latency is crucial for many 5G use cases that require real-time responsiveness, such as autonomous driving, remote surgery, smart manufacturing, etc2. Low cost, large bandwidth, and high availability are not the primary benefits of an Edge Cloud, although they may be achieved depending on the deployment scenario and the service level agreement. References: 1: Nokia Bell Labs Distributed Cloud Networks, Unit 1: Cloud Ecosystem, Section 1.2: Cloud Types 2: Nokia Bell Labs Distributed Cloud Networks, Unit 5: New Services Automation, Section 5.1: Industry 4.0 Use Cases

Isolation is the networking concept that ensures that each tenant or user of a cloud service has their own network configuration and resources, such as IP addresses, subnets, firewalls, and routers. Isolation provides security, privacy, and performance benefits for the cloud tenants, as they can control and customize their own network settings and avoid interference or conflicts with other tenants. Isolation can be achieved by using different techniques, such as VLANs, VXLANs, VPNs, or network slicing.

References:

• Nokia Bell Labs 5G Professional Certification - Distributed Cloud Networks | Nokia Distributed Cloud Networks, Unit 2: Cloud Technologies and Features, slide 10
• Nokia Bell Labs 5G Certification Program - Courses | Nokia, Distributed Cloud Networks, Unit 2: Cloud Technologies and Features

Isolation in networking, particularly in the context of cloud computing, refers to the separation of network traffic for different users or tenant environments within a shared infrastructure. This ensures that each tenant's data and applications remain private and inaccessible to other tenants. Isolation can be achieved through various means, including virtual LANs (VLANs), network virtualization, and software-defined networking (SDN) techniques. The core idea is to provide tenants with the illusion of a private, dedicated network environment, even though the underlying physical infrastructure is shared among multiple tenants. This enables each tenant to have their own network configuration, policies, and management, ensuring security and privacy within a multi-tenant architecture.

 The best option to complete the sentence is VNF Forwarding Graph. A VNF Forwarding Graph (VNF-FG) is a logical representation of a network service that consists of a set of interconnected Virtual Network Functions (VNFs) and the traffic flows between them1. The VNF-FG is used to orchestrate and manage traffic through VNFs by specifying the order and the requirements of the VNFs that need to be traversed by the traffic2. The VNF-FG also defines the connection points, virtual links, and network forwarding paths that are involved in the service delivery3. References: 1: VNF Forwarding Graph and Network Service-Beginner’s Guide, Introduction 2: A survey of VNF forwarding graph embedding in B5G/6G networks - Springer, Section 1 3: A Deep Reinforcement Learning Approach for VNF Forwarding Graph Embedding, Section I

Closed loop automation Comprehensive Explanation and References of Correct Answer: AI/ML based operation requires pre-defined policies, open APIs, and closed loop automation to enable intelligent and adaptive cloud management and orchestration. Pre-defined policies provide the rules and objectives for the cloud resources and services, such as performance, security, and cost. Open APIs allow the communication and integration of different cloud components and platforms, such as Nokia’s 5G Edge Slicing solution and Microsoft Azure edge and cloud. Closed loop automation enables the continuous monitoring, analysis, and optimization of the cloud ecosystem based on the feedback from the AI/ML algorithms.

References:

• Nokia Bell Labs 5G Professional Certification - Distributed Cloud Networks | Nokia Distributed Cloud Networks, Unit 4: Operating Your Cloud, slide 7
• Nokia, A1 and Microsoft deploy industry’s first 5G edge cloud network slicing solution for enterprises | Nokia, paragraph 4

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

 A fault detection event will trigger the auto-healing operation. Auto-healing is a feature of cloud networks that enables the automatic recovery of resources or services from failures or errors1. Fault detection is the process of identifying and locating faults in the network using various methods such as monitoring, logging, or testing2. When a fault is detected, the auto-healing operation will initiate the appropriate actions to restore the normal functioning of the network, such as restarting, repairing, or replacing the faulty components1. Threshold, warning message, and new status are not events that trigger the auto-healing operation. Threshold is a predefined value or limit that indicates the acceptable performance or behavior of a resource or service3. Warning message is a notification or alert that informs the user or operator about a potential problem or risk in the network4. New status is a change or update in the state or condition of a resource or service, such as active, inactive, or degraded.

References: 1: Nokia Bell Labs Distributed Cloud Networks, Unit 4: Operating Your Cloud, slide 9 2: Nokia Bell Labs Distributed Cloud Networks, Unit 4: Operating Your Cloud, slide 10 3: Nokia Bell Labs Distributed Cloud Networks, Unit 4: Operating Your Cloud, slide 11 4: Nokia Bell Labs Distributed Cloud Networks, Unit 4: Operating Your Cloud, slide 12 : Nokia Bell Labs Distributed Cloud Networks, Unit 4: Operating Your Cloud, slide 13

 Your apps need cloud resources which are allocated and then provisioned. Allocation is the process of assigning cloud resources to a specific app or service, based on the requirements and availability1. Provisioning is the process of configuring and activating the allocated cloud resources, making them ready to use by the app or service2. Commissioning, instantiation, starting, and distribution are not the correct terms to complete the sentence. Commissioning is the process of testing and verifying the cloud resources before they are allocated3. Instantiation is the process of creating an instance of an app or service, which is a running copy of the app or service that uses the provisioned cloud resources4. Starting is the process of launching an instance of an app or service, which can be done manually or automatically. Distribution is the process of spreading the cloud resources across different locations or domains, to achieve scalability, redundancy, or performance. Termination is the process of deleting or releasing the cloud resources that are no longer needed by the app or service.

References: 1: Nokia Bell Labs Distributed Cloud Networks, Unit 3: Cloud Resource Planning, slide 8 2: Nokia Bell Labs Distributed Cloud Networks, Unit 3: Cloud Resource Planning, slide 9 3: Nokia Bell Labs Distributed Cloud Networks, Unit 3: Cloud Resource Planning, slide 10 4: Nokia Bell Labs Distributed Cloud Networks, Unit 3: Cloud Resource Planning, slide 11 : Nokia Bell Labs Distributed Cloud Networks, Unit 3: Cloud Resource Planning, slide 12 : Nokia Bell Labs Distributed Cloud Networks, Unit 3: Cloud Resource Planning, slide 13 : Nokia Bell Labs Distributed Cloud Networks, Unit 3: Cloud Resource Planning, slide 14

 Distributed cloud is a concept that refers to the deployment of cloud services across multiple locations, such as public, private, hybrid, or edge clouds1. Cloud options are the different types of cloud models that can be used to meet the specific needs and requirements of different applications and users2. Cloud options are complementary with distributed cloud, as they enable the flexibility and scalability of cloud services across the cloud continuum3. Therefore, option B is the correct statement, while options A and C are incorrect. References: 1: Nokia Bell Labs Distributed Cloud Networks, Unit 2: Cloud Technologies and Features, Topic: Distributed Cloud Description 2: Nokia Bell Labs Distributed Cloud Networks, Unit 2: Cloud Technologies and Features, Topic: Cloud Options 3: Cloud continuum | Nokia, Overview

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

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.

The approximate maximum distance of an Edge Cloud from the end-user is 300KM. Edge Cloud is a type of cloud deployment that brings cloud resources closer to the end-user, reducing latency and improving performance1. Edge Cloud can be located at various distances from the end-user, depending on the use case and the network topology2. However, the general range of distance for Edge Cloud is between 10KM and 300KM3. 10000KM, 5000KM, and 10Q0KM are too far to be considered as Edge Cloud, as they would introduce significant delays and inefficiencies in the network.

References: 1: Nokia Bell Labs Distributed Cloud Networks, Unit 1: Cloud Ecosystem, slide 4 2: Nokia Bell Labs Distributed Cloud Networks, Unit 1: Cloud Ecosystem, slide 15 3: Nokia Bell Labs Distributed Cloud Networks, Unit 1: Cloud Ecosystem, slide 16

The properties related to a public cloud are for users, there is no cloud infrastructure operation and easy scaling. A public cloud is a cloud service that is offered by a third-party provider over the public internet, and is available to anyone who wants to use or purchase it1. Users of public cloud do not need to operate or maintain the cloud infrastructure, as it is the responsibility of the cloud provider2. Public cloud also offers easy scaling, as users can quickly and dynamically provision or release resources according to their needs2. Public cloud is suitable for applications that have unpredictable or variable demand, or that do not require a high level of security or customization3. References: 1: Nokia Bell Labs Distributed Cloud Networks, Unit 1: Cloud Ecosystem, Section 1.1: Cloud Types 2: Nokia Bell Labs Distributed Cloud Networks, Unit 2: Cloud Technologies and Features, Section 2.1: Cloud Computing 3: Nokia and DISH to deploy first 5G standalone core network in the public cloud with AWS, Press Release

Different paths for a NF providing Cloud Resilience are defined in a Network Service Descriptor. A Network Service Descriptor (NSD) is a document that describes the topology, configuration, and requirements of a network service. It specifies the network functions (NFs) that compose the service, the virtual links that connect them, and the forwarding graphs that define the traffic flows between them1. A NSD also defines the resilience policies for each NF, such as the number of instances, the scaling triggers, the fault management actions, and the alternative paths in case of failures2. A Network Function template, an NS Orchestrator configuration, and an NFV Orchestrator configuration are not the correct options to complete the sentence. A Network Function template is a document that describes the characteristics and requirements of a single network function, such as the virtualization environment, the resources, the interfaces, and the dependencies1. An NS Orchestrator configuration is a set of parameters that control the behavior and operation of the NS Orchestrator, which is a component that manages the lifecycle of network services3. An NFV Orchestrator configuration is a set of parameters that control the behavior and operation of the NFV Orchestrator, which is a component that coordinates the allocation and release of resources for network services3. References: 1: Nokia Bell Labs Distributed Cloud Networks, Unit 3: Cloud Resource Planning, Section 3.2: Network Function 2: Nokia Bell Labs Distributed Cloud Networks, Unit 3: Cloud Resource Planning, Section 3.3: Network Service Descriptor Role 3: Nokia Bell Labs Distributed Cloud Networks, Unit 4: Operating Your Cloud, Section 4.1: Industry Trends in Data Center Hardware

Kubernetes is an orchestrator, which is a software system that automates the deployment, scaling, and management of containerized applications1. Kubernetes allows users to define the desired state and configuration of their applications, and then ensures that the actual state matches the desired state2. Kubernetes also provides features such as service discovery, loadbalancing, storage management, and self-healing3. Therefore, option B best describes Kubernetes, while options A, C, and D are incorrect. References: 1: Nokia Bell Labs Distributed Cloud Networks, Unit 2: Cloud Technologies and Features, Topic: Microservices and Containerization 2: What is Kubernetes? | Kubernetes, Overview 3: Kubernetes - an overview | ScienceDirect Topics, Overview