VoIP

  Definition of VoIP: VoIP stands for voice over IP. It is the capability to carry normal telephony-style voice over an IP-based internet with POTS-like functionality, reliability, and voice quality. VoIP enables a router to carry voice traffic (for example, telephone calls and faxes) over an IP network. In VoIP, the DSP segments the voice signal into frames, which then are coupled in groups of two and stored in voice packets. These voice packets are transported using IP in compliance with ITU-T specification H.323.

Basic Telephone Signaling---

Line signaling: On-Hook:



Li  ne Signaling: Off-Hook 1. Signaling supervision



Line-Signaling: Dial-Tone 2. Call information (network to user)



Line-Signaling: Addressing 3. Dialing the destination 

Line-Signaling-Ringing  4. Call information (network to user)





 Line Signaling: Off-Hook 5. Call Completion 

How VoIP is used over the Internet

Top 10 Reasons how VoIP Saves
 * VoIP service has an average monthly rate of around $25
 * Most VoIP service providers offer unlimited long distance in the US, Canada, and Puerto Rico as a standard feature
 * International long distance rates are cheap
 * Some VoIP service provides offer some type of incentive for using their brand of service (e.g. 2 free months of service for referrals)
 * Some VoIP service providers includes premium features with basic plans, like caller ID, voicemail, three-way calling, telemarketer screening and call return
 * Subscribers have the option for portability; meaning they can take their number with you as you travel
 * Wireless VoIP allows users to make calls on internet-enabled cell phones, bypassing costly wireless roaming fees or high long distance rates
 * Most VoIP providers give you the option of paying in advance, offering even greater discounts to customers who do
 * In-network calls to other voip service subscribers are often free, even if the calling parties are in different parts of the world
 * Users can make PC-to-PC calls for free using SoftPhone programs.