NSM - Network Security Monitoring

NSM is the collection, analysis, and escalation of indications and warnings to detect and respond to intrusions. Inspired in name by Todd Heberlein’s “Network Security Monitor,” NSM is an operational model based on the Air Force’s signals intelligence collection methods. NSM integrates IDS products, which generate alerts; people, who interpret indications and warning; and processes, which guide the escalation of validated events to decision makers. We’ll describe Network Security Monitoring in the context of an intrusion that was detected and remediated using NSM principles.

Source: Book "Hacking Exposed: Network Security Secrets & Solutions, Fourth Edition"

ASP - Application Service Provider

An application service provider (ASP) is a company that offers individuals or enterprises access over the Internet to applications and related services that would otherwise have to be located in their own personal or enterprise computers. Sometimes referred to as "apps-on-tap," ASP services are expected to become an important alternative, not only for smaller companies with low budgets for information technology, but also for larger companies as a form of outsourcing and for many services for individuals as well.

ASP is also an abbreviation for Active Server Pages.

Read more about Application Service Provider or ASP

SaaS - Software as a Service

Software as a Service (SaaS) is a software distribution model in which applications are hosted by a vendor or service provider and made available to customers over a network, typically the Internet.

SaaS is becoming an increasingly prevalent delivery model as underlying technologies that support Web services and service-oriented architecture (SOA) mature and new developmental approaches, such as Ajax, become popular. Meanwhile, broadband service has become increasingly available to support user access from more areas around the world.

SaaS is closely related to the ASP (application service provider) and on demand computing software delivery models. IDC identifies two slightly different delivery models for SaaS. The hosted application management (hosted AM) model is similar to ASP: a provider hosts commercially available software for customers and delivers it over the Web. In the software on demand model, the provider gives customers network-based access to a single copy of an application created specifically for SaaS distribution.

Credits: TechTarget.com

HaaS - Hardware as a Service

See Infrastructure as a Service (IaaS)

IaaS - Infrastructure as a Service

Infrastructure as a Service is one of the three main categories of cloud computing service. The other two are Software as a Service (SaaS) and Platform as a Service (PaaS). It is a provisioning model in which an organization outsources the equipment used to support operations, including storage, hardware, servers and networking components. The service provider owns the equipment and is responsible for housing, running and maintaining it. Typically, the client pays on a per-use basis.

Infrastructure as a Service is also sometimes referred to as Hardware as a Service(HaaS).

Credits: TechTarget.com