Deploying Voice over IP on your network that offers the best quality is not hard if you pay attention to these 5 VoIP best practices. Good quality stable VoIP is about consistent steady data flow for calls and dependable signaling rather than having the maximum data transmission speeds. Choppy or broken voice on conversations can be avoided if good VoIP network practices are put in place inside your network and even though you may not have control on the wider WAN, you'll want to do everything in your power to make sure that quality issues are not inherent inside the LAN. It doesn't matter if you have five phones or a hundred deployed, it's best to stick to the following best practices when deploying a VoIP system on any network.
There are many good affordable routers, network appliances (firewalls) and managed switches that are widely available without having to spend a lot. Choose devices from known manufacturers that make products designed for intuitive configuration and get good reviews from those that have used them. Many of the well known companies offer excellent online resources for helpful guidance. Always attempt to reduce complexity when given the opportunity; less hardware, but better hardware is an advantage. Take precautions to prevent any double NAT on your network and understand the expected traffic flow so that your firewall is property configured. Remember, there is VoIP traffic in and out of the network and inside the network between phones.
Having totally separate physical networks is the ideal, however at times not easily achievable. If cabling infrastructure is just being installed, then by all means run separate cables for the phones and computers. VLAN tagging can be (and should be) used to integrate the phones using current existing cabling, or new cabling, separating the voice network from the data network. Using the switch port of the IP phone for the PC is typical in many VoIP deployments and does eliminate additional cabling. The phone is then used as a small switch which can under high bandwidth demand use some of the phones resources. (VLAN tagging should eliminate any potential audio issues as a result of the phone underperforming in this scenario.)
Competing network traffic can cause a degradation of two-way UDP voice communication. Packets of voice traffic are not guaranteed delivery; if other data causes a delay then that piece of voice is lost. With enough lost voice packets a person will start experiencing broken voice. Voice traffic is extremely susceptible to bandwidth limitations, clogged or slow links, or just non-voice traffic on the same VLAN (Virtual Local Area Network) taking precedence. Separating voice onto its own VLAN allows for more precise control and ensures that the voice traffic is independent with the highest priority. Provide easy to identify names to the VLAN IDs.
Set QoS (Quality of Service) rules that prioritize your VoIP traffic on all your network devices. A good VoIP router and configurable managed switches should include QoS settings that allow traffic to be given precedence across your network. Remember, QoS policies become easier to setup when you know where all the phones are.
Use traffic shaping to guarantee enough available bandwidth for voice. When setting up VANs group all your phones and tag them appropriately which will go a long way towards easier management.
In most cases it's a good idea to use POE switches and get IP phones
without the power supply. This will lower the cost of the phone, which
will offset the cost of the POE switches. Advantages are the elimination
of having an extra device on the floor around each desk and the ease of
rebooting all connected phones if ever needed by un-powering the switch.
(Remember, if power is lost to the phone the PC connected will loose it's
connectivity.) Remote workers will require the power supply, however.
If a cloud based PBX service is being used, then an added advantage depending on the provider, would be to move as many services as practical to that provider. Having one provider instead of several vendors, for services like video conferencing, faxing, project collaboration, chat, etc., brings simplification and ease of integration. If other cloud based services are used, then traffic shaping for voice priority is important. Some vendors make SD-WAN appliances that will help control bandwidth allocation.
Setting up your VoIP network using best practices requires some forethought, however goes a long way in creating a more stable and friendly voice network. Whether you have an on-premise IP-PBX or a cloud based hosted VoIP service, these tips are important. Security is always a concern, and should always be a high priority.
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