|
Feature |
VoIP |
PSTN |
|
Pricing |
Free (local and international) VoIP-to-VoIP calling, calls to landline and mobile phones have nominal charges. | No free calls. International calling is very costly. Phone plans usually cost around £15 to £30 per month depending on the service provider. |
|
Connectivity type |
All channels carried over one Internet connection | Dedicated telephone lines |
|
Required bandwidth |
Requires 10 Kbps in each direction | Requires 64kbps per line (in each direction) |
|
Call forwarding |
Some VoIP service providers offer free call forwarding, while others offer it for an extra fee. | Extra fee charged to enable this feature |
|
Call waiting |
Most VoIP service providers offer free call waiting. | Extra fee charged to enable this feature |
|
Call transferring |
Some VoIP service providers offer a free call transfer feature, while others do not support call transferring. | Extra fee charged to enable this feature |
|
Business continuity |
Service terminates when Internet connectivity is lost. Organizations must have an alternative solution for VoIP connectivity. | Service remains active during power outages because phone jacks don’t require electric power. But cordless phones require electric power and would be unusable in a power outage. |
|
Scalability |
Upgrades require more bandwidth and software updates. | Upgrades require purchasing more hardware and dedicated lines, which can be very costly. |
|
Remote extensions |
This feature is standard. | This feature requires dedicated lines for each extension and is very costly. |
|
Emergency calling |
Depends on the service provider, but emergency calling is usually not provided by VoIP. | Emergency calling is enabled. |
