Rui CarmoSkype used to be a proprietary VoIP application that provided a free peer-to-peer voice calling service (to other Skype users) and a prepaid service for dialing out to fixed or mobile phones anywhere on the planet.
It also provided basic presence and IM, but oddly enough, did not originally store your buddy list centrally and you had to add your contacts manually several times, which was plain stupid.
The protocol used is entirely proprietary and a nuisance to most ISPs and telcos because:
- Being P2P, it was hard to block (and many telcos did try)
- It was very creative in NAT traversal techniques (and many
ISPs did try to block it) - It was encrypted (using AES) and hard to snoop on (and many governments did try)
Skype was eventually acquired by Microsoft and Teams is its spiritual successor, but without all the P2P goodness.
Resources
| Category | Date | Link | Notes |
|---|---|---|---|
| Protocol Analysis | Pretty decent, even if outdated. |
||
| Call Recorder plugin for the Mac | |||
| 2005 | Be Afraid | ||
| 2008 | Skype for iPhone - It's official | Took them a good while. Of course, it will only work over Wi-Fi |