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What are the VoIP Cabling Requirements when installing a new phone system?

When planning for a new telephone system installation, the first consideration should be on the infrastructure. Therefore, what data cabling do I currently have or what are the VoIP cabling requirements that I will need.

VoIP or Voice over Internet Protocol is simply the transmission of voice communication over a data network, such as the internet.

We discuss What is VoIP in more detail in this article

We have also described How VoIP works here.

With a new installation, this is straightforward. Thus, you can have a new cabling design and installation to suit the new VoIP phone system. However, with existing data cabling there can be confusion.

In this case, there may be existing cabling, but it’s not suitable for several reasons.

  1. The existing data cabling is a legacy phone cable (Such as BT) and not suitable for data transmission.
  2. There is existing data cabling, but its quality of installation is not suitable for VoIP. (VoIP requires a quality of service)
  3. There are not enough ports for the required telephones.
  4. The structured cabling is not centralised and therefore unable to be controlled by the new phone switches.

In brief, where these situations are present, a new data cabling installation or upgrade is required.

What should I plan for VoIP cabling requirements?

VoIP telephones require a data cable to each phone that originates from a data cabinet with access to a data switch. To this end, the telephone switch hardware is installed in the data cabinets throughout a building, and the phones can be wired to any switch as long as they are linked.

The data cabling can be any category of cabling from Cat5e to above. Cat5e and Cat6a are the standard choices for 1-gigabit transmission speeds. Furthermore, 10-gigabit transmission starts with Cat6a and above. However, 1-gigabit is more than adequate for VoIP transmission.

The cabling installation has to be at a professional level. VoIP requires a quality of service (QoS) to enable uninterrupted call quality. Indeed, unlike WiFi or PC data transmission, VoIP will result in poor quality or dropouts with poorly installed data cabling. With the PC’s, it might just result in a slow loading or drop out of a hardly noticeable web page. However, with a phone, it can be an echo, buzzing, or loss of call. In short, all very frustrating and potentially costly if losing potential customers.

You may have existing cabling and not be sure if its suitable for VoIP.

We discuss this further in this article.

Elements of a suitable data cabling installation for VoIP

For the most part, the following elements should all be part of a cabling installation for VoIP.

  • A minimum of Cat5e with Cat6 and Cat6a preferred if scaling for higher speeds.
  • Installed with a well-known cabling brand
    • Many installations are undertaken with generic cheaper cabling systems, and these cause failure over time.
  • Installed onto Patch Panels inside a designated cabinet or set of cabinets
    • Avoid having the ends of cabling terminated onto plugs and plugged straight into switches. These fail over time
  • Terminated into designated outlet boxes
  • A dedicated cable for each telephone
  • Installed in correct containment and away from electrical cabling and interference
    • Electrical interference will cause noise and dropouts on the calls
  • Tested with a Fluke DSX or similar, and full test results supplied.
    • Without these, you will not know if the cabling is at the required standard and suitable for VoIP use.

The elements above should all be part of any data cabling installation. However, in many fit-out cases, the correct specialists are not used, and without these, the problems are only found later when you move in.

Evaluating existing structured cabling

When you have existing data cabling in place, there are similar checks you can put in place to check suitability. In this case, you would want to ensure the following

  • Check that there is enough cabling for each of your new phones.
  • Ensure that the existing cabling is Cat5e or above
  • Test your existing cabling with a Fluke DSX or similar

The test results will show if the existing cabling passes to the required standard for all data transmission. With any failure, the cabling will need to be replaced to ensure good telephone performance.

VoIP Installation Service – Free Surveys and Advice

If you are considering having a VoIP system you can see more information on Voice & Data systems here. We can provide advice and free surveys on any cabling requirements you have regarding a new phone system. In addition, we are also able to provide a service to test your existing data cabling. Furthermore, we would produce a report of suitability for those data cables


For further articles with regards to VoIP cabling requirements please visit our Knowledge Centre HERE

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