Disadvantages

• Less interoperable between technologies (overall) than conventional telecom

• More varied in quality than traditional telecom

  • Sound quality

• Reliability issues

  • Requires electrical power and Internet to be up

  • Security issues sometimes arise

• Electrical power required, unlike for PSTN phone service (battery back-up now being supplied by some).

• Access to 9-1-1 may be limited (depends on the company)