VoIP Spear servers work by pinging our users' endpoints. Ping is a nearly ubiquitous network tool that is used to test whether or not a computer/device is reachable across the Internet.
One problem with using ping is that ping uses the ICMP protocol while VoIP uses UDP. It was for this reason that we used UDP for testing when we first started developing VoIP Spear. We were aiming to support two types of testing -- basic testing would use ping/ICMP and advanced testing would use UDP. We envisioned that basic testing would be perfect for novice users because it's so easy to set up while advanced testing, on the other hand, would be more accurate and perfect for our advanced users.
After a few months, we realized two things:
So we decided to change course slightly and only offer ping/ICMP testing. It has meant that VoIP Spear is easy to use rather than a challenge. This decision also forced us to implement testing from multiple servers, something which lends an even greater degree of accuracy to our tests.
We've been delighted with the decision so far.