Note that most small business phone systems today include additional communication channels and team collaboration solutions, such as video calling, instant chat messaging, SMS texting, and file sharing.
Primary Rate Interface (PRI) is a T-1 transmission technology that has been widely used to support voice communications for over 50 years. It’s an interface standard used to deliver multiple lines of voice and data through physical copper lines that are part of your building’s physical infrastructure.

With German-engineered sound design, the new Snom series is designed to provide the small business market with the best sound quality and make it easier to add new people and integrate employees who use their mobile phone more than their desk phone. The new platform can start with just 2 lines and 2 phones, then easily grow up to 100 lines and up to 300 cordless, desk phones, and smartphone mobile users. And it’s your choice to have your phone services hosted in the cloud or installed to traditional landline phone lines in your closet — whatever makes the best financial sense for your organization right now.
For at least the next two years, these trends are likely to become important selling points in most VoIP vendor-customer pitches. While that's great, be sure to fully understand what's being offered and how the vendor is going to go about delivering it. Is a 5G implementation truly standards-based or are there still some proprietary hardware or software components? Have much will any new security measures affect overall voice performance, and does the vendor fully support the changing security requirements in important industry regulations, like HIPAA and SOX?