Skype P2P Communications
Transcending Any Network, Firewall or NAT You Can Throw Its Way
Skype is a peer to peer (P2P) Internet network utility developed in Luxembourg by Niklas Zennstrom and Janus Friis (creators of KaZaA). At its core, Skype is a messenger; however, it is a messenger with many additional features.
SkypeOut is a service that competes with open source VoIP protocols, such as H.323, SIP, and IAX. Skype can bridge networks using its free desktop application. Its power and flexibility comes from its P2P communications architecture. The Skype communication structure avoids network stoppages by using a decentralized communication model. Skype’s decentralized model makes each user a node in its network.
Skype to Skype (SkypeIn) user communication is absolutely free as a text or voice communications system, similar to MSN and Net Meeting. SkypeOut is a pay service that allows Skype users to access telecom or PSTN (Public Switched Telephony Network) just like VoIP. This allows the Skype user to call anyone across the world at anytime.
Skype’s Short Story
Skype has had an interesting run in the short time it has been around. Skype was purchased by Ebay for $2.6 billion. Skype may have recently entered the first phase of a potentially deadly fate suffered by many innovative software solutions: imitation followed by the subsequent marginalization by Microsoft.
Skype’s paid service SkypOut is the result of the company’s agreement with telecom networks to use their networks in the same manner that VoIP services can. It’s similar to VoIP in that the Skype uses the internet to place long distance calls, but it doesn’t replace your phone service like VoIP. The Skype user is billed local call rates for long distance calls, whether it is to a landline or mobile phone anywhere in the world.
To pay for the Skype service, you must purchase Skype credits. These are purchased from Skype in advance, but they’re only good for 180 days.
Today there are Skype phones that connect to your PC (running the Skype client) via USB and operate like a cordless. The handset will even let you call your SkypeIN contacts. Skype phones are being taken one step further with Skype compatible cell phones. The Skype cell will run a Skype client over your phone’s wireless network and allow you to use your SkypeOut credits for your cell phone. Soon there will be a Symbian (S60) version of the Skype client for many popular cell phones, including Nokia and Sony Ericsson. Pocket PCs can already use the Skype interface, using a Wi-Fi connection to the internet to make long-distance calls. With innovations like Skype, our world is becoming interconnected with less use of expensive telecom networks. However, this technology and its related networks have a long way to go before it is completely seamless.
Skype is not free; it requires a tick client running on a PC. The latest and immediate future iterations of Skype will see it running through 3G and Wi-Fi networks. Skype is neither seamless or trouble free: Skype is known for latency problems and isn’t as reliable a voice communications line as telecom or even most VoIP services.