Cloud vs. classic telephone system - which solution will suit your company in 2025?

The classic telephone system - proven technology with limits

The classic telephone system (PBX) is physically located in the company and is connected directly to the public telephone network. Previously, the connection was made via ISDN. However, at the latest since it became clear that ISDN would be switched off, classic telephone systems have also been connected with internet-based SIP trunks. You can find out why ISDN is being switched off in the article "ISDN switch-off Austria - What companies need to know now!".

Advantages of a classic telephone system:

• High stability and reliability: the PBX runs locally in your server room, independent of services from the cloud.
• Full control: All data and functions are stored internally, which is particularly interesting for sensitive industries and due to the current geopolitical situation.
• Many years of experience: Many companies have existing expertise in their IT departments and can operate the systems themselves.

Disadvantages of a classic telephone system:

• Acquisition and maintenance costs: hardware, installation and regular updates cause initial as well as ongoing costs.
• Low flexibility: relocation, new extensions or integration of modern tools (e.g. Microsoft Teams, CRM systems) require the relevant knowledge.
• Limited scalability: As the company grows, it is often necessary to invest in additional hardware and software.

Particularly in times of remote work and hybrid working models, traditional telephone systems reach their limits.

The cloud telephone system - telephony directly from the cloud

The cloud telephone system (also known as VoIP telephony ) runs entirely over the internet. Providers host the software on secure servers and companies access it via apps, browsers or IP telephones. The article "What is the difference between VoIP and cloud telephony?" goes into more detail about the difference between Voice-over-IP and a cloud telephone system.

Advantages of a cloud telephone system:

• Maximum flexibility: employees can make calls from anywhere - in the office, at home or on the move.
• Simple scaling: new users can be added or removed with a click.
• Cost transparency: No expensive hardware, no maintenance contracts - you usually pay per user.
• Integration into existing systems: Links with Microsoft 365, CRM or helpdesk tools are easy.
• Automatic updates and security: The provider takes care of maintenance, data protection and regular software updates.

Disadvantages of a cloud telephone system:

• Dependence on the internet: Without a stable connection, voice quality can suffer.
• Data protection issues: Companies must ensure that the provider is GDPR-compliant and uses servers in the EU.
• As a service: Payment "as a service" results in ongoing costs regardless of the period of use.

Which telephone system for companies?

A cloud telephone system is best suited for companies. However, it depends on your company structure, industry and IT strategy whether a classic or cloud telephone system is right for your company:

There will be a clear trend in 2025. The cloud telephone system is increasingly becoming the standard for companies. It is flexible, cost-efficient and can be seamlessly integrated into modern IT structures. Nevertheless, traditional telephone systems retain their raison d'être in certain industries and scenarios - especially when maximum control, independence and data security are paramount.

However, investing in the right communication solution today lays the foundation for efficient and future-proof business processes. When switching to a cloud telephone system in particular, it is worth taking a close look at the provider, especially with regard to security standards, data sovereignty and the support offered.

If you are currently considering switching to a cloud telephone system, be sure to take a look at our article "Cloud telephone system: The 5 most common mistakes when switching and how to avoid them!". There you will find practical tips that will make the switch to cloud telephony much easier for you.