Glossary of Terms

​A B C D E F G H I J K L M N O P Q R S T U V W X Y Z


Activity Log API
Allows contract owners and administrators to discover the log of activity under a specific contract. This makes it possible to audit user activities as well as to make changes to any resources. The activity is grouped by contract and can be refined using date ranges. Activity information is READ-ONLY, so all calls made against the Activity Log API will be handled using GET requests.


An application programming interface (API) is an interface that allows the user to access information from another service and integrate this service into their own application. Through a set of defined requests, the asking application is allowed to access limited pieces of the called upon application’s functionality. APIs are used to share limited functionality between programs. See application programming interface


Ansible is an IT automation tool that allows users to configure, deploy, and orchestrate advanced tasks, such as continuous deployments, or zero downtime rolling updates.

Application Load Balancer

Application Load Balancer (ALB) is a pre-configured VDC element that operates at Layer 7 (HTTP) of the Open Systems Interconnection (OSI) model.

Application Programming Interface (API)

A set of methods and rules that allow services to interact, access, and exchange data.

Availability Zone

These are centron data centers, divided into separate areas (also known as "fire zones"). You can enhance reliability and set up high-availability scenarios by deploying redundant virtual servers and storage devices across multiple Availability Zones.


Backup Unit Manager

A backup unit manager is an application that schedules, manages and operates data backup processes on a computer, server or network device. It is an integrated application that works on client/server architecture for extracting backup data copies from a source computer or IT environment to a remote storage facility.

Billing API

The centron Cloud Billing API can be used to retrieve information about resource usage and invoices.

Block Storage

Block storage is a type of IT architecture in which data is stored as a file system. Block storage provides endless possibilities for storing large amounts of information, as well as guarantees the safety of resource planning systems, and provides instant access to the required amount of data without delay.


A bucket is a user-defined storage area in a cloud storage system. Each bucket can be divided into folders.


Chef: Knife plugin

Chef is a popular configuration management tool. It allows simplified configuration and maintenance of both servers and cloud provider environments through the use of common templates called recipes.


centronCTL is a tool to help you manage your centron ccloud resources directly from your terminal. centronCTL CLI is currently under development. We are working on adding new commands and use-cases in order to support all the operations available in the Cloud API.

Cloud API

Allows you to perform various management tasks, such as spinning up additional servers, adding volumes, setting up networking, etc. It is designed to allow users to leverage the same power and flexibility as the DCD visual tool. Both tools are consistent with their concepts and are well suited to make work smooth and intuitive.

Cloud Block Storage

centron ccloud Hard Disk Drive (HDD) and Solid State Drive (SSD) Block Storage allow the customer to make use of a dual-redundant storage system. Each block storage created by the customer is stored on two storage servers, providing active-active redundancy. For additional data protection, every storage server is based either on a hardware RAID system or on a software RAID system.

Cloud Computing

Cloud computing is the delivery of information technology services over a network, usually the internet. In the cloud computing model, infrastructure, data, and software are hosted by the vendor and delivered to the user as a service.


Cloud-init is a defacto multi-factor package that performs early initialization of a cloud instance. It is a set of community-maintained scripts that configures virtual machines based on information from the metadata service.

Cloud Storage

Cloud storage is a model of computer storage in which data is stored in facilities (often multiple facilities) managed by a hosting company (cloud service provider) and is accessed remotely by the user via a network.

Configuration Management Tools

Config Management Tools are an automated approach to maintaining computer systems and software in a known, consistent, state.


A container is an abstract unit of software that is an independent executable unit that contains everything needed to run an application. Containers have specific parameters and can run programs, work tasks, or specific tasks. The small size, high speed, and portability of containers are due to the absence of a guest operating system in each instance. This way, containers can simply use host OS components and resources.

Core Network

Centron ccloud operates a high availability core network at each location for the redundant connection of the product platform. All services provided by centron ccloud are connected to the Internet via this core network.
The core network consists exclusively of devices from brand manufacturers. The network connections are completed via an optical transmission network, which, by use of advanced technologies, can provide transmission capacities of several hundred gigabits per second. Connection to important Internet locations in Europe and America guarantees the customer an optimal connection at all times

Cross Connect

A cross-connect is a physical, hardwired cable that provides a direct connection between two different termination locations within a data center. Cross connects enable colocation customers to establish high-performance, dedicated connectivity to one another within the data center – providing increased reliability and lower latency over network connections standardly used outside of a data center.


CSI (Container Storage Interface) is an attempt to standardize the interaction between container orchestration engines and storage providers. This solution is being promoted by the Kubernetes, Docker, and Mesos. Its meaning is that storage providers implement one addition, and container orchestration platforms undertake to support the CSI interface.


A cube, or data cube refers is a three-dimensional (3D) (or higher) range of values that are generally used to explain the time sequence of an image's data. It is a data abstraction to evaluate aggregated data from a variety of viewpoints.


Database as a Servce (DBaaS)

DBaaS (also known as Managed Database Service) is a cloud computing service that allows users access to, and the use of, a cloud database system. Users can access this without purchasing and setting up their own hardware, installing their own database software, or managing the database themselves.

Database Cluster

A database cluster is a collection of databases that is managed by a single instance of a running database server. After initialization, a database cluster will contain a database named postgres, which is meant as a default database for use by utilities, users and third party applications.


Denial-of-service attacks ( DoS attacks) and distributed-denial-of-service attacks ( DDoS attacks) are attempts to make a computer, computer network, or service inaccessible or more difficult for the intended customers. The difference between a 'regular' DoS attack and a distributed-DoS attack is that in the latter case several computers attack their target simultaneously.

Ddos Protect

centron DDoS Protect is a managed Distributed Denial of Service defense mechanism, which ensures that every customer resource hosted on centron ccloud is secure and resilient against Layer 3 and Layer 4 DDoS attacks. This is facilitated by a filtering and scrubbing technology, which in event detection of an attack filters the malicious DDoS traffic and lets through only the genuine traffic to its original destination. Hence, enabling applications and services of our customers to remain available under a DDoS attack.

Digital Asset

A digital asset is an entity that exists in binary format and comes with a right to use. If there's no right to use, then it is not considered an asset. Common examples include images, audio files, spreadsheets, multimedia, email, websites, digital documents, etc.

Distributed Network

A distributed network is a computer network system that distributes the programming, software, and data across multiple computers. These computers may be in close proximity or geographically dispersed, but they work and communicate together as one system.


The Domain Name System (DNS) is a system used to convert a computer's hostname into an IP address on the Internet. For example, if a computer needs to communicate with the web server, your computer needs the IP address of the web server


Elastic computing

The ability to dynamically provision and de-provision computer processing, memory, and storage resources to meet changing demands without worrying about capacity planning and engineering for peak usage.

External Network

Depending on the location, different capacities for transmitting data to or from the Internet are available for operating the centron ccloud service. Due to the direct connection between the data centers at the German locations, the upstream can be used across locations.



Failover is switching to a redundant or standby computer server, system, hardware component or network upon the failure or abnormal termination of the previously active application, server, system, hardware component, or network in a computer network. Failover and switchover are essentially the same operation, except that failover is automatic and usually operates without warning, while switchover requires human intervention.


A firewall is a network security device that monitors incoming and outgoing network traffic and permits or blocks data packets based on a set of security rules. Its purpose is to establish a barrier between your internal network and incoming traffic from external sources (such as the internet) in order to block malicious traffic like viruses and hackers.

Flow logs

Flow logs is a feature that allows you to capture data related to IPv4 network traffic flows. Flow logs can be enabled for any network interface of a virtual machine (VM) instance and Network Load Balancer, as well as the public interfaces of the Network Address Translation (NAT) Gateway.

Forwarding rules

Forwarding rules define how the Network Load Balancer and Application Load Balancer distributes traffic to the targets. See forwarding rules for NLB and forwarding rules for ALB.


The File Transfer Protocol (FTP) is a standard communication protocol used for the transfer of computer files from a server to a client on a computer network.



We follow the binary interpretation of the gigabyte (also called gibibyte, 'GiB'), where a gigabyte equals 1024 megabytes, a megabyte equals 1024 kilobytes, and a kilobyte equals 1024 bytes. This defines one gigabyte as 1,073,741,824 bytes.



A hard disk drive (HDD), hard disk, hard drive, or fixed disk

Hot Plug

Hot plugging is the addition of a component to a running computer system without significant interruption to the operation of the system
Host Machine
A host machine is a piece of physical hardware that hosts virtual machines.
Hybrid Cloud – A hybrid cloud is a cloud computing environment that is comprised of a mix of private cloud, public cloud, and on-premises solutions. In a hybrid cloud, private and public cloud infrastructures remain distinct from one another but are bound together by technology that allows data and services portability between them.



Infrastructure as a service (IaaS) is a type of computing infrastructure that includes computing resources: virtual servers, storage, networks. These are a kind of virtual "computers" on which you can install, for example, an operating system, software, or applications. Тhe IaaS model provides the user with a complex infrastructure to run their IT solutions using cloud technologies.


A system image is a copy of the entire state of a computer system, stored in some non-volatile form such as a file. A system is said to be capable of using system images if it can be shut down and later be restored to exactly the same state. In such cases, system images can be used for backup.


An index is a method of sorting data by creating keywords or a listing of the data.

Internal Network

centron ccloud operates redundant networks at each location. All networks are operated using the latest components from brand manufacturers with connections up to 100 Gbps.
centron ccloud uses high-speed networks based on InfiniBand technology both for connecting the central storage systems and for handling internal data connections between customer servers.

IP Address

An IP address is a unique address that identifies a device on the internet or a local network. IP stands for "Internet Protocol," which is the set of rules governing the format of data sent via the internet or local network.




Live Vertical Scaling

LVS technology permits you to scale the number of CPU cores and amount of RAM while the server is running, without having to restart it. Please note that Windows only allows scaling the number of CPU cores, but not the amount of RAM. For scaling to more than eight CPU cores, Windows requires a reboot.

Load Balancer

Load balancing refers to the process of distributing a set of tasks over a set of resources (computing units), with the aim of making their overall processing more efficient. Load balancing can optimize the response time and avoid unevenly overloading some compute nodes while other compute nodes are left idle.


Managed Kubernetes

Facilitate a fully automated setup of Kubernetes clusters.

Managed NAT Gateway

The Managed NAT Gateway masks the source, providing another layer of protection against external compromise. All IP addresses generated during the process are transferred to public IPs using DNS. See NAT Gateway

Monitoring API

Sets alarms and alerts, and retrieves alarm history.

Monitoring as a Service (MaaS)

Monitoring as a service is one of many cloud computing delivery models under anything as a service. It is a framework that facilitates the deployment of monitoring functionalities for various other services and applications within the cloud.


A multi-cloud strategy is the concurrent use of separate cloud service providers for different infrastructure, platform, or software needs. A multi-cloud approach can help prevent vendor lock-in, and may help an enterprise deal with diverse workloads and partners.


Multi-Tenancy is a mode of operation for software in which multiple instances of one or many applications run in a shared environment. In a cloud computing model, pooled physical and virtual resources are dynamically assigned and reassigned to tenants according to consumer demand.


NAT Gateway

A NAT gateway is a Network Address Translation (NAT) service. You can use a NAT gateway so that instances in a private subnet can connect to services outside your VPC but external services cannot initiate a connection with those instances.

Network Address Translation (NAT)

Network address translation (NAT) is a method of mapping an IP address space into another by modifying network address information in the IP header of packets while they are in transit across a traffic routing device. The technique was originally used to avoid the need to assign a new address to every host when a network was moved, or when the upstream Internet service provider was replaced, but could not route the networks address space. It has become a popular and essential tool in conserving global address space in the face of IPv4 address exhaustion. One Internet-routable IP address of a NAT gateway can be used for an entire private network.

Network Load Balancer

Network Load Balancer (NLB) is a pre-configured VDC element that provides connection-based layer 4 load balancing features and functionality.


NFS (Network File System) is used to access information contained on the drives of other computers.


Network Interface Card (NIC) is a component that provides networking capabilities for a computer. It may enable a wired connection (such as Ethernet) or a wireless connection (such as Wi-Fi) to a local area network.


A node is any computer that connects to a blockchain network. 'Full' nodes store the entire distributed ledger from the first (genesis) block to the present and participate in blockchain consensus. 'Light' nodes are used by resource-constrained devices for application-specific purposes, such as reading specific blockchain data and submitting new transactions to full nodes for inclusion in the ledger.

NVMe Volume

Non-Volatile Memory Express (NVMe) is a standard hardware interface for solid state drives (SSDs) that uses the PCI Express (PCIe) bus. NVMe takes advantage of the parallel I/O of the PCIe bus and the low latency of SSDs. It supports speeds up to six times faster than SATA-based SSDs and 10 times faster than hard drives and is especially noticeable when reading and writing large files.


Object Storage

Object storage (also known as object-based storage is a computer data storage architecture that manages data as objects, as opposed to other storage architectures like file systems which manages data as a file hierarchy, and block storage which manages data as blocks within sectors and tracks.
Each object typically includes the data itself, a variable amount of metadata, and a globally unique identifier. Object storage can be implemented at multiple levels, including the device level (object-storage device), the system level, and the interface level. In each case, object storage seeks to enable capabilities not addressed by other storage architectures, like interfaces that are directly programmable by the application, a namespace that can span multiple instances of physical hardware, and data-management functions like data replication and data distribution at object-level granularity.

Object Storage Key Manager

An application used to store and manage encrption keys for Object Storage.


Database optimization is the strategy of reducing database system response time**.** Databases provide us with information stored with a hierarchical and related structure, which allows us to extract the content and arrange it easily. There are plenty of options to choose from for business and companies.


Point-in-Time Recovery (PITR)

PITR refers to PostgreSQL’s ability to start from the restore of a full backup, then progressively fetch and apply archived WAL files up to a specified timestamp.
PITR is important when someone has accidentally deleted a table or records in a database or if something has gone wrong which has corrupted the existing database. The fastest solution to this would be to retrieve the transaction logs and recover the database from the last “known good” point. PITR is done differently for individual databases.

Power Button

You can choose to Suspend, Resume, or Reset Cubes instances by clicking the Power button at the top right of the Inspector pane or in the context menu of the Cubes instance.


Provisioning is the process of setting up IT infrastructure. It can also refer to the steps required to manage access to data and resources, and make them available to users and systems.
Provisioning is not the same thing as configuration, but they are both steps in the deployment process. Once something has been provisioned, the next step is configuration.
When the term “provisioning” is used, it can mean many different types of provisioning, such as server provisioning, network provisioning, user provisioning, service provisioning, and more.

Public IPv4 Addresses

Every virtual network interface card that is connected to the Internet is automatically assigned a public IPv4 address by DHCP. This IPv4 address is dynamic, meaning it can change while the virtual server is operational or in the case of a restart.
Customers can reserve static public IPv4 addresses for a fee. These reserved IPv4 addresses can be assigned to a virtual network interface card, which is connected to the Internet, as primary or additional IP addresses.

Private IPv4 Addresses

In networks that are not connected to the Internet, each virtual network interface card is automatically assigned a private IPv4 address. This is assigned by the DHCP service. These IPv4 addresses are assigned statically to the MAC addresses of the virtual network interface cards.
The use of the IP address assignment can be enabled or disabled for each network interface card. Any private IPv4 addresses pursuant to RFC 1918 can be used in private networks.



A database query is a request for a database’s data so we can retrieve or manipulate it.


Remote Console

A terminal or workstation in a remote location that is used to monitor and control a local computer.

Reseller API

Allows managing contracts and their associated admin users under your master reseller account. Registration in the centron Cloud Partner Program is required for use of this REST-based API.

Routing Table

A routing table, or routing information base (RIB), is a data table stored in a router or a network host that lists the routes to particular network destinations, and in some cases, metrics (distances) associated with those routes. The routing table contains information about the topology of the network immediately around it.


S3 Object Storage

Create buckets and store objects with this S3 compliant service.

S3 Object Storage API

Enables storage, retrieval, display, and deletion of objects (or binary files) within the centron ccloud S3 storage offering.
Scalability is the ability of a process, system, or framework to handle a growing workload. In other words, a scalable system is adaptable to increasing demands. The ability to scale on demand is one of the biggest advantages of cloud computing.


SDK’s are like a toolbox that contain special libraries that can be used to easily manage your cloud servers by using your preferred development or coding language. They hold tools, libraries, relevant documents, sample code, processes, and or guides for use on that particular platform.


A server is a piece of computer hardware or software (computer program) that provides functionality for other programs or devices, called "clients". This architecture is called the client–server model. Servers can provide various functionalities, often called "services", such as sharing data or resources among multiple clients, or performing computation for a client.
A single server can serve multiple clients, and a single client can use multiple servers. A client process may run on the same device or may connect over a network to a server on a different device. Typical servers are database servers, file servers, mail servers, print servers, web servers, game servers, and application servers.


A snapshot is the state of a system at a particular point in time. It can refer to an actual copy of the state of a system or to a capability provided by certain systems.

Software Development Kit (SDK)

Software Development Kit (SDK) are like a toolbox that contain special libraries that can be used to easily manage your cloud servers by using your preferred development or coding language. They hold tools, libraries, relevant documents, sample code, processes, and or guides for use on that particular platform.


A solid-state drive (SSD) is a solid-state storage device that uses integrated circuit assemblies to store data persistently, typically using flash memory.

SSH keys

SSH keys are used for easier authorization on various services. When creating storages based on centron Linux images, you can inject SSH keys into your VM for setting up SSH access so that you can use SSH for secure communication.


Storage is a process through which digital data is saved within a data storage device by means of computing technology. Storage is a mechanism that enables a computer to retain data, either temporarily or permanently.



Targets are the compute resources, such as VM instances, containers, microservices, or appliances, to which the traffic is distributed for processing. Network Load Balancer backend serves registered targets using an IP address and a TCP port.
Targets can be added or removed and capacities scaled without disrupting the overall flow of connection requests.


A token represents some utility, resource, or asset value that can be bought, sold, or traded on an existing blockchain, like Ethereum. Tokens are often used in decentralized applications.

Two Factor Authentication (2FA)

2FA is an extra layer of security used to make sure that people trying to gain access to an online account are who they say they are. First, a user will enter their username and a password. Then, instead of immediately gaining access, they will be required to provide another piece of information. This second factor could come from one of the following categories:
  • Something you know: This could be a personal identification number (PIN), a password, answers to “secret questions” or a specific keystroke pattern
  • Something you have: Typically, a user would have something in their possession, like a credit card, a smartphone, or a small hardware token
  • Something you are: This category is a little more advanced, and might include biometric pattern of a fingerprint, an iris scan, or a voice print
With 2FA, a potential compromise of just one of these factors won’t unlock the account. So, even if your password is stolen or your phone is lost, the chances of a someone else having your second-factor information is highly unlikely. Looking at it from another angle, if a consumer uses 2FA correctly, websites and apps can be more confident of the user’s identity, and unlock the account.




A virtual data center is a collection of cloud resources for creating an enterprise-grade IT infrastructure. VDC resources include the processors, memory, disk space, and networks from which virtual machines are built.

Virtual Network

centron ccloud allows virtual entities to be equipped with network cards (“network interface cards”; NICs). Only by using these virtual network interface cards it is possible to connect multiple virtual entities together and / or to the Internet.

Virtual Server

Scalable instances with a dedicated resource functionality.

Virtual Machine

A virtual machine (VM) is the virtualization/emulation of a computer system. Virtual machines are based on computer architectures and provide the functionality of a physical computer.VMA virtual machine (VM) is the virtualization/emulation of a computer system. Virtual machines are based on computer architectures and provide functionality of a physical computer.



Write Ahead Logs (WAL)

WALs are used in nearly all modern RDBMS systems to provide durable and atomic transactions.
Changes to the data contained in a PostgreSQL database cluster managed by a single PostgreSQL server process is possible only via transactions. The modifications made to the data by transactions are recorded as an ordered sequence of WAL records. These records are written into fixed-length files called WAL segment files, or simply WAL files.

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