Unified communications as a service (UCaaS) supports the same functions as its premises-based unified communications (UC) counterpart. The main difference is UCaaS adheres to a cloud service delivery model.

• Voice and telephony – This area includes fixed, mobile and soft telephony, as well as the evolution of PBXs and IP PBXs. This also includes live multimedia communications, such as video telephony.
• Conferencing – This area includes separate audio conferencing, video conferencing and web conferencing functions, as well as converged unified conferencing capabilities.
• Messaging – This area includes email, which has become an indispensable business tool, voicemail and unified messaging (UM) in various forms. The vast majority of email deployments are implemented via either Microsoft Exchange (cloud or on premises) or Google Gmail (cloud only).
• Presence and instant messaging (IM) – These play an increasingly central role in next generation communications, enabling the aggregation and publication of presence and location information from and to multiple sources. This enhanced functionality is sometimes called “rich presence.”
• Clients – Unified clients enable access to multiple communications functions from a consistent interface. These may have different forms, including thick desktop clients, thin browser clients and mobile PDA clients, as well as specialized clients embedded within business applications.
• Communications-enabled applications – This broad group of applications has directly integrated communications functions. Key application areas include consolidated administration tools, collaboration applications, contact center applications, workstream collaboration applications and notification applications.

1. Multi-tenant – customers share a common (single) software instance
2. Multi-instance – each customer receives its own software instance

Both architectures possess such cloud characteristics as shared infrastructure (for example, data centers, racks, common equipment and blades), shared tools (for example, provisioning, performance and network management tools), per-user-per-month pricing, and elasticity to dynamically add and subtract users.

Read more information on each vendor’s strengths and cautions from Gartner’s 2016 UCaaS Magic Quadrant published August 2016 on the Gartner website or contact Tier4 directly for a thorough breakdown on the Unified Communications as a Service solution providers.

Enterprises can secure UCaaS from four types of providers.

1. CSPs – These are the legacy network service providers, with core strength in voice and data services.
2. Technology vendors – provide a UCaaS offering marketed directly to end users
3. Application specialists – both platform provider and service provider
4. System integrators – usually provide UCaaS by running commercial UC applications (Cisco or Microsoft) out of their own data centers