What is the full form of the phone

What is a SIP phone?

There are many SIP telephones: from entry-level IP telephones and cordless versions to high-end business models, everything is included. But what are SIP telephones actually? Which brand manufacturers are particularly popular and when is such a purchase worthwhile? You will find out in this guide. In addition, we will inform you which SIP telephones are particularly recommended.

1. What is a SIP phone?

1. What is a SIP phone?

At a SIP phone, also IP phone or VoIP phone called, it is a phone that is used as a hardphone or softphone in IP telephony. SIP telephones no longer require a conventional telephone connection, but can be easily connected via the existing Internet infrastructure. The Connection to the network takes place by Ethernet or wirelessly via WIRELESS INTERNET ACCESS. Most IP phones use it SIP (Session Initiation Protocol), a network protocol that regulates the establishment and termination of VoIP connections.


SIP telephones as hardphones hardly differ in appearance from conventional analog and ISDN telephones and can also be operated in this way. However, in contrast to traditional telephones, they use a different technology that enables data transmission over the Internet. However, in order to be able to use SIP telephony, a connection to a VoIP provider is required. Depending on the model, a hardware-based SIP telephone has numerous functions such as holding, toggling, forwarding, three-party conferences, telephone books or BLF.

Well-known manufacturers of IP telephones include:

The Placetel cloud telephone system can generally be used with all SIP-capable telephones.


SIP telephones can also be used as software solutions, so-called softphones. These can be seen as a useful addition to the hardphone and enable calls to be made using internet-enabled end devices, e.g. using a computer, laptop, tablet or smartphone. With the help of soft clients, a high degree of flexibility is achieved, as this enables location-independent use. And the best thing about it: Even when you are out and about, you can stay available at your office number if you wish.

Softphones for Android

Softphones for iOS

Especially the softphones Zoiper and Bria are very popular with users. You can find a detailed list of all softphones for Windows, Mac and Linux in our softphone guide.

SIP phone or IP phone - what are the differences?

The terms SIP telephone and IP telephone are used synonymously, with the latter actually being the correct variant. However, since most IP telephones use the open Session Initiation Protocol (SIP), the term SIP telephone has also spread. Telephones that support the open standard have the great advantage that they are compatible with most IP telephone systems. Only a few IP telephones use a closed standard. The disadvantage here, however, is that these can only be used with the manufacturer's own telephone systems.

2. When is a SIP telephone worthwhile?

2. When is a SIP telephone worthwhile?

Are you about to switch to All-IP or have you already been converted? You are now wondering whether you should keep your existing devices or switch to new SIP telephones? Contrary to what some claim, it is not necessary to switch to new devices for SIP telephony. Most routers nowadays have one or more connections to which analog or ISDN telephones as well as DECT telephones or their base can be connected. If you have a router without such a telephone interface, a connection with a VoIP adapter is possible.

But even if a modern, future-proof SIP phone is not necessary for Internet telephony, such a purchase can still make sense. Especially if you had already thought about getting new equipment in the near future. In the following we would like to briefly introduce you to the advantages of SIP telephones compared to conventional telephones:

1. Many useful additional functions

If you opt for a modern SIP desk phone, in addition to the standard functions such as hold, toggle, forwarding and participation in telephone conferences, other features such as unified communication or BLF realize. This enables you to improve teamwork even more. With BLF (busy lamp field) the availability or call status of other employees is displayed, provided that these have been stored on a speed dial key. So you always have the perfect overview of which employee is currently on the call. The Yealink T46S SIP telephone shown above shows 10 function keys, 2 of which light up green (employees are not on the phone at the moment) and 2 light up red (employees are currently talking). In addition, a call can easily be picked up on your own telephone if an employee is not at the desk.

2. Excellent voice quality
Having an IP phone connection is thanks to the High definition voice technology generally a significantly better voice quality than with a conventional landline line. However, the prerequisite for HD telephony is that both parties have an IP telephone. Furthermore, the router and the technology used by the call participant must also support HD Voice.

3. Telephoning from any location

As already mentioned above, softphones or soft clients can also be used for SIP telephony. These enable location-independent accessibility through use on the mobile phone or laptop.

4. Easy setup
Many VoIP providers offer auto-provisioning for certain SIP telephones. The selected end device immediately receives the current firmware and the correct settings, so that there is no need to set up all standard settings.

The Placetel cloud telephone system. Known from these media.
3. SIP phone purchase recommendation

3. SIP phone purchase recommendation

There are a few things to consider when buying an IP phone. The first question that arises is whether you would prefer to buy a desk phone, a DECT phone or a WLAN phone.

The following decision criteria help here:

1. How would you like to make a call?

  • corded or cordless?

2. What should the phone be able to do or what connections should it have?

  • BLF, PoE, multiple SIP accounts, HD audio, gigabit switch, Bluetooth, unified communications

3. Do you need programmable buttons?

4. Which design do you prefer?

5. Which user interface do you get along well with?

  • Haptic buttons or touchscreen?

Newer desk phones have the great advantage that they are frequently available large displays that are easy to display and easy to navigate. Furthermore, desk phones often offer more calling features as DECT or WLAN telephones. For example, some SIP telephones are Unified Communications-capable and equipped with extremely practical function keys.

But also DECT and WLAN telephones of course have their advantages. Through the cordless option When it comes to telephoning, these SIP telephone variants are particularly suitable for employees who have to move around a lot at work, e.g. for warehouses. If you are interested in a DECT telephone, our DECT telephone guide is suitable. Here you will also find a comparison of prices and providers and you will find out why WLAN telephones are inferior to the DECT variant in many ways.

But regardless of whether you ultimately opt for a modern desk, DECT or WLAN telephone, you should make sure that the open SIP standard is used when purchasing a new one. That is not said with the term “VoIP” alone. As before, there are still a few manufacturers who bring VoIP telephones onto the market with their own, closed standard. The disadvantage here, however, is that these telephones cannot be used with any other SIP telephone system other than that of the manufacturer.

The Best SIP Phones: A Comparison

To support you in your purchase decision, we have an IP telephone for you
Test selected by Comparison.org.

Among other things, the test compares:

  • the possible simultaneous VoIP calls
  • the phone number memory
  • Customer ratings
  • the display size
  • the advantages
  • the price

According to comparison.org and according to our expertise, the top SIP phones include:

Cheap price range
Mid price
Upper price range

For the business sector, we at Placetel can especially recommend SIP telephones from Cisco, Snom and Yealink.

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4. FAQ - common questions

4. FAQ - common questions

1. What does the abbreviation SIP mean?
SIP stands for Session Initiation Protocol, a network protocol that is used to set up and clear VoIP connections.

2. What is the advantage of SIP?
The advantage of SIP is that it is an open standard that is now used by many device manufacturers and is gradually becoming the standard protocol for VoIP. If the SIP standard is used with an IP telephone, it is compatible with most IP telephone systems with SIP protocol.

3. What is a SIP address?
In systems based on SIP, each subscriber has its own SIP address. In terms of structure, this is similar to an email address. It consists of two components and consists of the subscriber's SIP user and the domain name of the registrar server. An example for a SIP address would be: “sip: [email protected]

4. What is SIP telephony?
SIP telephony is understood to mean common voice communication via the Internet protocol. Other common terms are IP telephony, Voice-over-IP or Internet telephony. Thanks to SIP telephony, it is now possible to conduct data and telephone calls over the same network. Unlike analog telephone connections, IP connections are linked to broadband and thus enable telephony via the Internet connection.

5. What is a SIP number?
A SIP number, often also called an Internet number, is assigned by a VoIP provider. This is a completely normal number that is used for IP telephony and that is assigned by the Federal Network Agency (BnetzA). SIP numbers do not differ from conventional numbers. Users can order numbers from all German local networks and even international numbers. You can find out more about VoIP numbers on our phone number page.

6. What is a SIP trunk?
A SIP trunk is a type of telephone connection based on a data line. It is used to connect local telephone systems to the Internet and, if required, to modern VoIP providers. You can find more information in our SIP Trunk blog article.

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