Bandwidth.com improved their online VoIP Test at http://www.bandwidth.com/tools/voipTest
. The free test measures critical factors of your Internet connection such as throughput, latency, and SIP port tests to see if your connection can handle VoIP calls.
A critical factor in deciding whether your connection can handle VoIP is upload speed. While connections supplied by cable companies and traditional telecom companies have fast download speed, the upload speed is usually much slower, such as 400 Kbps for ADSL and 400-600 Kbps for cable. Using such a connection for both Internet and VoIP applications may result in poor call quality. A T1 connection from Bandwidth.com provides 1.54 Mbps of upload speed.