If you've ever renewed a broadband or leased line contract based on the biggest speed number on the quote, you've probably had the same experience afterwards: the connection "tests fine" on a speed checker, yet video calls still freeze, VoIP calls crackle, and cloud apps feel sluggish during busy periods. That's because download speed is only one measurement, and often not the one that matters most for how your business actually uses the internet. Before you sign anything new, it's worth understanding what else is going on in that connection, and how to test for it yourself.
Why download speed is the wrong headline number
Download speed tells you how much data a connection can pull in a single burst, which matters for things like downloading large files. It tells you almost nothing about how stable the connection is under everyday conditions, with multiple people on video calls, cloud backups running, and phone calls going out at the same time. A line can advertise 100Mbps and still be unusable for VoIP if the underlying connection is inconsistent.
The metrics that actually predict performance
For real-world business use, three other measurements matter far more than the headline speed:
- Latency: the delay between sending data and it arriving. High latency makes video calls feel laggy and out of sync, even if the speed is fine.
- Jitter: the variation in that delay over time. Jitter is the main cause of choppy, robotic-sounding VoIP calls, because voice data arrives at uneven intervals.
- Packet loss: when small chunks of data never arrive at all and have to be resent. Even a small amount of packet loss causes dropped words on calls, frozen video, and cloud apps that hang or time out.
A connection with low speed but low latency, low jitter and no packet loss can feel far more reliable day to day than a faster line that's inconsistent.
How to test before you sign
Most providers will let you trial a connection, or at least provide performance data from similar installations in your area, before you commit to a contract. A few practical steps:
- Run tests at different times of day, including your busiest periods, not just first thing in the morning when traffic is low.
- Use a tool that reports latency, jitter and packet loss alongside speed, not just a basic speed test.
- Test from the location and equipment you'll actually use day to day, not just a laptop plugged directly into the router in an empty office.
- If you rely on VoIP, ask the provider for the specific latency and jitter figures they guarantee, not just an uptime percentage.
- Where possible, get a short trial period written into the contract so you can walk away if real-world performance doesn't match what was promised.
What good looks like
As a rough guide for business connectivity: latency under 30ms, jitter under 10ms, and packet loss close to zero are the kinds of figures that support smooth VoIP and video calls. Anything significantly outside those ranges is worth questioning before you sign, regardless of what the advertised speed says.
Leased lines versus broadband
This is also where the difference between shared broadband and a dedicated leased line really shows up. Standard business broadband is typically shared with other users in your area, so performance can dip at peak times even if it tests well when you first connect it. A leased line gives you a dedicated connection with symmetrical speeds and consistent latency, which is why it's usually the better choice for businesses that depend heavily on VoIP, video conferencing or cloud-based systems, even though the headline speed might look similar on paper.
Choosing the right connectivity isn't about chasing the biggest number on a quote, it's about matching the connection to how your business actually works day to day. Valetech Solutions helps Greater Manchester businesses test and compare real-world connectivity options, from standard broadband to dedicated leased lines, so you can make a decision based on performance rather than a sales pitch. Get in touch with Valetech Solutions before you renew or switch providers.