sip and skypeSIP and SKYPE both are the means to enjoy IP telephony. Find out the differences between the two.

FCC report of 2010 suggests that 23 % of all voice-based communications in the United States was performed via SIP-based communication system. SIP or Session Initiation Protocol is a signaling protocol which is necessary for initiating a communication and multimedia session over the Internet.

Communication over the Internet is becoming a hyped topic these days. Internet-based telephone systems are gaining name and fame. The day is not far when IP telephony will completely eradicate the conventional telephony. Internet-based telephony is full of sophisticated features. VoIP, which is a group of technologies, help in the delivery of communication and multimedia sessions via an IP network. VoIP renders the entire process of making calls very economic. Not only this, the voice quality being delivered in a VoIP-based call is far better than that delivered in a call made via PSTN. Unlike POTS (Plain Old Telephone Service), VoIP is evolving and improving itself day by day.

POTS and PSTN give a 10-digit number to each one who connects with them for their servcie. On the other hand, VoIP generates a user ID for each user. So it is more likely that all of us would like to remember a much smaller and easier user ID instead of mugging up a long and complicated telephone number.

Business and personal communications are becoming enormous on daily basis; therefore, it is almost becoming mandatory to switch over to VoIP. Most of the time, businesses and even the households are left puzzled over choosing between SIP and Skype. VoIP implementation varies from company to company. It depends on the specific needs of a business. SIP is one of the protocols which is quite often used these days to initiate Internet based voice communication.

SIP and Skype are two different methodologies and are an integral part of VoIP. They are very much different from each other. The applications for which they are extensively used worldwide are same for both but the technicality involved in the operation of both these thespians is highly different.

There is a central server which is used by both SIP and Skype for the validation and establishment of connections between their users.

Central server is also used for storing the IP addresses, Contact lists, and other data. Central server can be used for differentiating between SIP and Skype. Skype is managed via a single server whereas in case of SIP, each service provider has his own individual server.

In case of Skype, there is a single service provider and a single server therefore, usernames cannot be repetitive and each user has to have a unique username across the world. SIP is being managed by a number of service providers and a number of servers therefore, usernames can be repetitive.

Skype user is strictly able to communicate with another Skype user only. He cannot communicate with the network of any other service provider. On the other hand, a SIP user has the capability of communicating with the network of any other service provider. This difference thus generates variability in the call routing of the two. A SIP service provider has to establish a connection between his server and the server of the service provider of the receiver. On the other hand, Skype works under the same server.

The way in which SIP and Skype transmit voice packets and the quality of voice itself differs remarkably between the two.

When we speak over the microphone, codecs convert the analog voice signals into digital signals. These digital signals are compressed and moved over the line. On reaching the destination, these digital signals are decompressed and decoded back to analog signals by codecs. Codecs used by SIP for coding and decoding are G711 and G727 whereas Skype uses iLBC and iSAC codecs for coding and decoding the signals. Unlike SIP, Skype uses encryption for delivering media sessions including voice, text, or multimedia file. SIP prefers RTP protocol whereas Skype prefers UDP protocol.

SIP operates in a Public domain whereas Skype operates in a Private domain.

SIP is an IETF (Internet Engineering Task Force) standard protocol. It manages only few details and features such as the internet availability at user’s end, authenticity of the user, and calling features such as call forwarding, call queue, and more. All the other applications are managed by RTP (Real-time Transport Protocol), SDP (Session Description Protocol), STUN (Session Traversal Utilities for Network Address Translator), and some other protocols of IETF. On the contrary, Skype manages all the applications on its own and does not depend on any protocol of IETF. The way in which Skype gets the things done and the technology it utilizes for the same still remains undisclosed as it is a privately operating endeavor. If you want to work with Skype, you will have to install their setup. Once installed successfully on your system, you will not require any other supplementary protocol for the proper running of Skype.

Skype is based on peer-to-peer model.

Calls and other multimedia sessions are transmitted under a single server. There is no middleman involved in connecting the calls between two Skype users. SIP works on the traditional server-client model. There are many intermediaries involved in connecting a call made from one SIP server to the other. This is because calls are not made under the same server.

Peer-to-peer model of Skype might be a very suitable and perfect choice for individuals who want to communicate among themselves. But this application is not suitable for large business setups. Adopting SIP for managing communication in an enterprise and even outside is a wise decision. The decision is all yours. Choose prudently. Skype and SIP both are good when talked of individually but when situations differ, these two act differently.

Article WritingViola Allen is a SIP and VoIP expert, currently employed with SIPServices Dot Com. Her passion is to write about the recent technological advancements, including Cloud Hosted PBX and SIP Trunking. Her main motive is to gain more and more information about the latest technological advancements in the industry.