chapter 1 Flashcards
explain tier system
tier 1: data centers have a single path for power and cooling, with no redundancy. They have an expected uptime of 99.671% (28.8 hours of downtime)
tier 2: data centers have a single path for power and cooling, with some redundancy components. They have an expected uptime 99.741% (22 hours of downtime per year)
tier 3: data centers have multiple paths for power and cooling, with one path active and one standby. They can perform maintenance and upgrades without disrupting the service. They have an expected uptime of 99.982% (1.6 hours of downtime per year)
tier 4: data centers have multiple paths for power and cooling, with both paths active and fully redundant. They can withstand any single point of failure without affecting the service. They have an expected uptime of 99.995% (26.3 minutes of downtime per year)
describe redundancy
redundancy is the practise of duplicating components or functions in a system to enhance its reliability and availability
explain what load balancing is
is a technique that distributes the workload among multiple servers, ensuring optimal performance and availability. load balancing can help cloud computing to handle high traffic, reduce latency and prevent overload.
explain what scalability is
the ability of a system to accommodate larger or smaller workloads by adding or removing resources manually or programmatically
explain what elasticity is
the ability of a system to automatically adjust the amount of resources allocated to it closely following the current demand and traffic.
explain what HA (high availability) is
is a feature that ensures that the services are always available and minimizes the downtime. High availability can help cloud computing to maintain the business continuity (BC)
explain what DR (disaster recovery) is
is a process that ensure that the data is always backed up and recoverable in the event of massive failures or disasters. Can be achieved by using multiple redundant servers, storage, and networks, but now also across different locations which are also known as availability zones or regions
explain basic security measures that go into providing confidentiality and integrity
Encryption: converts the data into a unreadable form, that can only be decrypted with a key
Firewalls: filter the incoming and outgoing traffic, blocking or allowing it based on predefined rules
Authentication: verifies the identity of the users, using methods such as passwords, tokens or biometrics
Authorization: determines the level of access to files and applications that the users have, using policies and roles
describe and give azure examples of the 3 main it as service models
Infrastructure as a service (IaaS): the most basic service model, where users can access and manage raw computing resources such as servers, storage, networks and operating systems. Example -> azure virtual machines (VMs)
Platform as a service (PaaS): PaaS is the next level of service model, where users can access and manage pre-configured computing platforms such as databases, web servers, development tools and middleware. Example -> azure app service
Software as a service (SaaS): SaaS is the highest level of service model, where users can access and use ready-made software applications such as email, office, CRM and ERP. Example -> Microsoft 365
explain 3 delivery models of cloud computing
Public cloud: is the most common and accessible delivery model, where cloud services are provided by a third party cloud provider over the public internet, and are shared among multiple users. Public cloud offers the most scalability, cost-effectiveness and variety of services but also has less privacy and customization
Private cloud: is the most exclusive and secure delivery model, where cloud services are provided by an organization over a private network to the client and are used by a specific group of users. Private cloud offers the most privacy, and customization but is also less scalable, cost-effective and has a lower variety of services
Hybrid cloud: is the most flexible and balanced delivery model, where cloud services are provided by an combination of public and private clouds and are integrated and coordinated through a common platform. Hybrid cloud tries to offer the best of both worlds, allowing users to leverage the advantages of each cloud type and mitigate the disadvantages of each cloud type
describe main public cloud providers
Amazon web services (AWS): market leader by public cloud platform, offering 200 services across 25 categories such as compute, storage, database, networking, security, machine learning and IoT
Microsoft azure: second largest public cloud provider and the fastest growing one, offering over 200 services across 18 categories such as compute, storage, database, networking, security, AI and blockchain
Google cloud platform (GCP): third largest public cloud provider and the most innovative one offering over 100 services across 20 categories such as compute, storage, database, networking, security, data analytics and AI
explain azure regions
Regions: is a geographical area that contains one or more data centers where azure services and resources are deployed and hosted. Azure regions are grouped into geographies such as “Europe” or “America”
explain azure zone
Zone: is a logical grouping of physical resources within a region such as servers, storage and network devices that provide high availability and fault tolerance for azure services and resources. Each zone has a number and is isolated from other zones in the same region
explain azure subscriptions
subscription is a logical container that represents a billing and management boundary for azure services and resources. Each subscription has a name and id. Customers can have multiple subscriptions under the same azure account and can use them to organize their resources by project, department or environment
explain azure resource groups
a resource group is a logical container that groups together related azure services and resources such as VMs, storage account and network interfaces. Each resource group has a name and a location. Customers can use resource groups to manage their resources as a unit and to apply policies, permissions and tags