SIP... or Session Internet Protocol... isn't necessarily a new communications concept. It has been around awhile although it seems to be garnering a resurgence in Telephony applications today. But... how do you explain what SIP is when asked?
Good luck with this one, trying to explain SIP to technical people is tough enough.
Here's some very simple short statements that may help...
- SIP enables telephony over the internet network
- SIP allows us to packetize and prioritize voice traffic over digital circuits.
- SIP is a way voice is packed into a digital signal that is then enabled for transfer through the internet.
- SIP digs a channel in an IP network so voice/video can flow between two (or more) places. When you finish talking, SIP shuts the channel up.
- It's an internet protocol like HTTP for web browsing, only this one is used to make a phone-like connection between computers, pda, voip-phones or other devices that can talk over the internet.
- SIP is a protocol that allows unlike mediums to communicate. All you really need to know is that SIP is the new PRI and is more cost effective from a trunking perspective.
- SIP has nothing to do with the internet.... regardless of where, when, or how voice traffic is being transmitted. f it's being sent as 0's and 1's... SIP is what differentiates voice from all other data.
- SIP enables you to eliminate the cost of maintaining two networks (POTS + Ethernet) by putting your phone traffic on your Ethernet network.
- SIP is a business-class, integrated voice and data service with connectivity provided to your IP-PBX (a telephone switch that supports voice over IP)
Or... you may explain to a non-technical person by describing the SIP VoIP operation like this:
1. Callers and callees are identified by SIP addresses.
2. When making a SIP call, a caller first locates the appropriate server and then sends a SIP request. (The most common SIP operation is the invitation).
3. SIP or VoIP is a technology that allows you to make calls between devices, be it over the local network or over the Internet (Managed or un-managed). SIP is a standards based technology that behaves very much like your old telephone line but just uses the Internet as its medium.
4. Instead of directly reaching the intended callee, a SIP request may be redirected or may trigger a chain of new SIP requests by proxies.
5. Users can register their location(s) with SIP servers.
6. SIP messages can be transmitted either over TCP or UDP
7. SIP messages are text based and use the ISO 10646 character set in UTF-8 encoding.
8. Lines must be terminated with CRLF.
9. Much of the message syntax and header field are similar to HTTP.
10. Messages can be request messages or response messages.
Taken From :How to Explain SIP to a Non-Technical Person