While choosing an intercom for your property might seem like a simple task, you know that the right access control experience can be the difference between receiving your delivery or missing it entirely. Having the right property technology is becoming increasingly important to prospective and current tenants, whether they’re residential or commercial.

So, it may be time to consider adding a layer of convenience and security to your property by installing an internet-powered SIP intercom. Read on to learn what SIP intercoms are, how they work, and why a SIP intercom is the best entry system for your building.

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The best SIP intercom

The best SIP intercoms use all of the powerful capabilities of the internet. And that means being able to connect to the latest devices, like smartphones and even Apple Watches.

ButterflyMX is a SIP intercom that takes full advantage of the internet’s potential. By letting residents open doors with their smartphones, ButterflyMX takes your property into the modern age while adding a variety of secure and convenient features for tenants and staff.

Since the ButterflyMX SIP intercom has a camera, tenants and visitors can video chat with each other. This also significantly improves security, ensuring only authorized guests can enter the property. Meanwhile, virtual keys provide a way for tenants to grant seamless access to visitors such as house cleaners and dog walkers. Furthermore, managing package delivery has never been easier thanks to ButterflyMX’s system of delivery PINs and passes for couriers.

For building staff, ButterflyMX’s web-based dashboard has features like an audit trail of all door release events, which helps them better secure the property. Also, the ButterflyMX intercom integrates with other property management services to create one, cohesive smart building ecosystem.


What is a SIP intercom?

A SIP — or Session Initiation Protocol — intercom is an electronic device that uses the internet to let a building’s tenants communicate with guests seeking entry. It also allows tenants to buzz in their guests without having to physically go down to their front door or gate.

SIP intercoms are the next evolution in the field of access control because they use the internet to transmit data. The analog intercoms of the past depended on wiring throughout the building to function. This made them expensive to install and limited them to on-premises use only.

All types of properties find SIP intercom systems useful, including residential apartments, office complexes, and student housing.

SIP intercoms have four parts:

  1. Base station. The base station is hardware installed at the property’s entrance. One of its most important components is a SIP intercom speaker. The intercom speaker allows visitors to speak with a building tenant through the base station.
  2. Server. An intercom SIP server is a central hub that keeps a database of access credentials and manages the entire intercom system. In the past, this server was installed on the property near the base station. Now, many modern SIP intercoms use the cloud, eliminating the need for buildings to purchase and maintain a server.
  3. Substations. Substations are the hardware that tenants use to talk to visitors. They can take many different forms. For example, a substation might be hardware mounted in a tenant’s unit, a SIP intercom phone, or even a resident’s smartphone.
  4. Door strike. A tenant who wants to grant entry to their visitor presses the ‘door open’ button on their substation, which sends a signal to the door strike to unlock. Door strikes can be electric or magnetic.


Watch how ButterflyMX works:


How does a SIP intercom work?

SIP intercoms work by using the internet to transmit audio and video data between a building tenant using a substation and a visitor at a base station. SIP helps to ensure that data being transmitted arrives successfully and in the correct order.

The Session Initiation Protocol is one type of internet protocol, which is a set of rules that computers use to send data over the internet. SIP is designed to enable two computers to initiate and shut down a data transmission session.

To transmit audio or video data specifically, intercom providers may also use VoIP, or the Voice over Internet Protocol. Thus, the term ‘VoIP intercom’ is commonly used as well. While the technical details of each protocol are different, the terms ‘IP intercom,’ ‘VoIP intercom’, and ‘SIP intercom’ are generally interchangeable.

Regardless of what they’re called, internet-based intercoms provide building residents, staff, and visitors with features like remote property access, video capabilities, and mobile apps.


sip phone on wall


The relationship between SIP and VoIP

We’ve mentioned that SIP intercoms are also sometimes referred to as VoIP door intercoms. This is because the two protocols, SIP and VoIP, are often used together.

VoIP, or the Voice over Internet Protocol, is actually an umbrella term for a collection of protocols that all work together to make sure the audio data from a call is transferred successfully over the internet. SIP is only one of these protocols and can act independently. For example, while VoIP only transfers audio or video data, all sorts of computers use SIP to initiate transfers of other types of data.

Put simply: Whether an IP intercom is classified as a VoIP or SIP intercom, there won’t be any noticeable differences for tenants, residents, or visitors.


Here’s how a guest contacts a tenant using a SIP intercom:

  1. Visitor uses base station to select a tenant. Visitors do this by selecting the tenant they’re visiting from a directory in the intercom base station.
  2. Base station establishes connection with substation. The intercom substation and the base station establish a connection using the SIP protocol.
  3. Visitor and tenant communicate. SIP enables data transmission. Meanwhile, the substation and base station can use another protocol, such as VoIP, to actually transmit data and allow the tenant and the visitor to communicate. SIP video intercoms also allow tenants and visitors to see each other.
  4. Tenant grants visitor entry. After the tenant presses a button on their substation, the electronic door strike releases and the visitor can enter.



Why your building needs a SIP intercom

Now that you know how a SIP-based door phone works, you can better appreciate the benefits of an internet-powered access control system.

SIP intercom benefits include:

  • Wireless capabilities. SIP door intercom base stations and substations can communicate wirelessly. As a result, you’ll save on installation costs since you don’t have to tear down and rebuild walls to lay wiring. And if your property has a gate, installing a SIP gate intercom means you don’t have to dig up the pavement to run outdoor wiring.
  • Added functionality. Digital intercoms can store and retrieve large amounts of data at lightning-fast speeds. So, this leads to features that benefit tenants, like virtual keys and delivery passes.
  • Administrative tools for staff. Some SIP intercoms simplify administrative tasks for property staff. For example, SIP intercoms provide features like web-based dashboards and integrations with other property management services.



In summary, a SIP intercom is the best way to ensure secure and convenient access control at any building. By harnessing the power of the internet, you can simplify your tenants’ lives. What’s more, you’ll also free your staff from administrative busywork and let them focus on creating a world-class resident experience.


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Ferdison Cayetano

I’m a proptech enthusiast from New Jersey who’s looking forward to the innovations that will revolutionize real estate.

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