Glossary

Macintosh Operating System. Formerly known as Mac OS X.

A server that receives, stores, sends, and processes emails.

An Internet site that attempts to install malware onto your device, usually to steal your personal information or to disrupt the operation of your system.

A megabit.

A unit of measure used to describe the rate of data transmission equal to one millions bits per second.

A unit of frequency equal to 10^6 hertz, which is defined as one cycle per second. 

A database used for managing the entities in a communication network. Often associated with SNMP.

Microsoft Exchange Server is a calendaring and mail server that runs exclusively on the Microsoft Windows Server product line. A hosted version of Exchange Server is available as part of Office 365

Two-part identifier for file formats and format contents transmitted over the Internet.

Measure representing the overall quality of a system or stimulus, calculated by taking the arithmetic mean of individual values of quality. Often used for, but not limited to, video, audio and audiovisual quality.

Receives email messages from a mail user agent (MUA) and cooperates with a mail transfer agent (MTA) to deliver the mail.

Software that transports email messages from one computer to another by using a client-server architecture.

Switch that filters and forwards packets based on MAC addresses and network addresses. A subset of LAN switch.

Scheme that allows multiple logical signals to be transmitted simultaneously across a single physical channel.

The existence of multiple clients sharing resources (services or applications) on distinct physical hardware. Due to the on-demand nature of cloud, most services are multitenant.

Resource record in DNS that specifies a mail server responsible for accepting email messages for a recipient’s domain. Includes a preference value to prioritize mail delivery when there are multiple mail servers.

Server connected to a network that resolves network names into network addresses.

The process of modifying IP address information in IP packet headers while in transit across a traffic routing device. The simplest type of NAT provides a one to one translation of IP addresses.

A NAT device, configured by a user, that performs network address translation in a VPC public subnet to secure inbound Internet traffic.

An automated email message from the mail system informing the sender that there was a delivery problem with an email message that they sent.

API used by applications on an IBM LAN to request services from lower-level network processes. These services might include session establishment and termination, and information transfer.

Layer 3 of the OSI reference model. This layer provides connectivity and path selection between two end systems. The network layer is the layer at which routing occurs.

Networking protocol for clock synchronization between computer systems over packet-switched, variable-latency data networks.

Resource-intensive OSPF area that carries a default route, static routes, intra-area routes, interarea routes, and external routes. The only OSPF areas that can have virtual links configured across them and that can contain an ASBR.

Nonrelational database systems that are highly available, scalable, and optimized for high performance. Instead of the relational model, NoSQL databases (like Amazon DynamoDB) use alternate models for data management, such as key–value pairs or document storage.

A network administration command-line tool available for many computer operating systems for querying the Domain Name System (DNS) to obtain domain name or IP address mapping or for any other specific DNS record.

Form of encryption where the plaintext is mixed with a large amount of non-cipher material.

Authentication method with an internal IP address as destination. Offline Authentication Works with all protocols (for example, POP3).

Refers to a location other than the subject site. Example: Barracuda Cloud Storage subscription plans provide diverse offsite storage that scales to meet your changing data requirements.

An Amazon EC2 pricing option that charges you for compute capacity by the hour with no long-term commitment.

Remote procedure call system based on calling conventions used in Unix and the C programming language.

At the place where a business or activity happens. Compare to offsite.

A free and open-source cloud computing software platform used to control pools of processing, storage, and networking resources in a datacenter.

Orthogonal sparse bigram transformation. In machine learning, a transformation that aids in text string analysis and that is an alternative to the n-gram transformation. OSB transformations are generated by sliding the window of size n words over the text, and outputting every pair of words that includes the first word in the window.

Scanning email messages from local users before any potentially harmful messages can be delivered to others on the Internet.