Business phones, explained.
Independent guides to VoIP, SIP trunking and cloud phone systems, with free calculators to size your lines, agents and bandwidth.
Do the maths before you buy.
Two free calculators built on standard telecom formulas. They run in your browser and store nothing.
Learn the systems behind the phones.
Clear explanations of the technology and the buying decisions that come with it.
What is VoIP? How internet calling works
VoIP turns your voice into data packets and sends them over the internet. Here is how it works, what you need, and where it falls short.
What is SIP trunking? How it works and when to use it
SIP trunking connects your business phone system to the phone network over the internet. Learn how channels, pricing models and setup work.
Cloud phone system: what it is and how to choose one
A cloud phone system runs your business phones over the internet with no on-site PBX. See features, trade-offs and a simple way to compare providers.
Most-read guides.
What is a PBX? On-premise vs hosted PBX explained
A PBX is the private phone system that routes calls inside and outside a business. Compare traditional, IP and hosted PBX options.
VoIP vs landline: cost, reliability and which to choose
A fair comparison of VoIP and traditional landlines on cost, call quality, power outages, features and emergency calling.
VoIP phone system for small business: a buyer's checklist
What to check before you pick a business VoIP provider: features, bandwidth, contracts, support, porting and emergency calling.
Quick answers.
What does Tyscom cover?
Plain-English guides to VoIP, cloud phone systems, SIP trunking and PBX, plus free calculators for phone line sizing and bandwidth.
Are the calculators free?
Yes. They run in your browser and nothing you enter is sent to us.
Does Tyscom sell phone services?
No. Tyscom is an independent information site and does not sell or resell phone services.
How accurate are the Erlang and bandwidth results?
They use standard formulas, but real networks add variation. Treat the results as planning estimates and confirm with your provider.
Size your phone lines before you buy.
Free calculators for lines, agents and bandwidth.
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