Release & Upgrade
Release Notice for RMS V2.5.24
Release Notice for UMSV1.1.41
Finder v1.0.9
OM50G V177 P2.2
OM20G V177 P2.2
NeeHau Client V2.0.0.23 (with OM20/20G/50/50G)
OM20G V177 P2
OM50G V177 P2
OM80E V177 P3

What is the purpose of SIP in VoIP?
The Difference Between PBX And PSTN
What Is The Meaning Of Hosted Pbx ?
How Do You Choose An IP PBX For Your Small Business?
How To Install New Rock OM20 IPPBX-OM20g Installation
Why are PBX's Becoming VoIP Based?
What's the Meaning of PBX And How does a PBX system work?
How Is Ip Pbx Different From Traditional PBX?
How does a hotel phone system work?
What is PSTN gateway?
Is VoIP Phone worth it for a small business?
The Difference Between A Ip Phone And A Voip Phone
Can you use your old phone with VoIP?
What Is The Sip Response Code?
What is VoIP Server And How a VOIP Server Works
What is SIP 500 error
What Is Voip Gateway
Ip-pbx Vs Voip Gateway
Best PBX Phone System Features for Businesses
How to Setup a VoIP System in Office
PBX Software Features
Traditional IP PBX configurations
How to choose business telephony system
IP PBX vs. Traditional PBX
PBX IP PBX and VoIP technology Advantages
Guide to Business VOIP PBX
PBX phone systems for small businesses
How Does a SIP Gateway Work?
SIP, VOIP & IP Phones
VoIP Phone Systems - Create the Perfect Business Phone System
What Is a PBX Phone System
How much business Phone System
What is a PBX System
Why use VOIP
What are the advantages of VoIP services
FXO/FXS Gateways
Which Voip Phone System Is Right for Your Business
How do I choose a VoIP provider
Flexible Hotel Phone Systems From New Rock
How Can VoIP Help Hotels Cut Cost
Hospitality Technology Solutions
Modern phones for hotel rooms
VoIP to the hospitality industry
Hotel phone system improves hotel service experience
Why is a Hotel Phone System Important
How Hotel Phone Systems
The Importance Of Using Hotel Phone System
Hotel VOIP telephone system
Small Hotel Phone System for up to 50 Rooms
How Hotels Use a PBX Phone System

Application Notes
How to Integrate MX Gateway with OM IP-PBX
Interconnect Two PBXs with FXO Gateways
Interconnect Two or More Extension Lines with FXS Gateways
Connecting MX100G-S SIP-ISDN Gateway to Elastix
Connecting MX100G-S SIP-ISDN Gateway to Asterisk
Expanding PBX Extensions to Remote Sites through IP Network
Multi-site Configuration for Gateways with Analog PBX
How to Troubleshoot Caller ID Detection Issues on FXO Port
Security Configuration Guide for New Rock OM Series IP-PBX
Connecting FXO Gateway to Asterisk
Connecting FXO Gateway to Elastix
Tie Trunk Configuration for OM with Elastix

Training Materials
What is VoIP gateway?
What’s the Difference between VoIP Gateway and SIP Trunk?
Smart Switchboard Introduces Exclusive Premium Customer Services
What's the Difference Between VoIP Gateway and ATA?
What's the Difference Between VoIP gateway and SBC?
New Rock’s New Gateway Security measures
Global VoIP Gateway Service Provider
How to Setup VoIP Gateway - A Complete Installation Guide
What is HX&MX VoIP Gateway Default Password?
Auto Provisioning
Six Practices for Audio Security
“PSTN failover” - Strong Support for High-availability IP Audio Communications
New Rock IP-PBX: Your All-In-One IP Office Telephony System
Connecting E1/T1-Based PBX to IP Telephony Networks
Popular IP-PBX Features Favored by Highly Efficient Officers
Five-star Customer Services
Top Three Advantages of Gateways with Imbedded VPN Clients
Low-Cost, High-Quality Gateway
Smart FoIP
Two Typical Applications for Telephone Networks
IPv6’s Top Three Advantages in VoIP Applications
MX100G-S SIP-ISDN Trunking Gateway Training
MX Series VoIP Gateway Training


Installation & Maintenance
OM SIP Trunk Configuration Documentation
NAT Traversal Service---Configuration video
User Guide for Finder V1.0.9
IP-PBX Installation (Video)
OM20G&OM50G Quick Installation Guide
OM80E Quick Start Guide
OM200G Quick Start Guide
OM500 Quick Installation Guide
HX4G&MX8G Quick Reference Guide
MX60E Quick Installation Guide
MX120G Quick Installation Guide
MX100G-S Quick Start Guide
SX3000 Quick Installation Guide
PT2400 Quick Installation Guide
PT4800 Quick Installation Guide

Marketing Materials

What is the purpose of SIP in VoIP?
Update Time:2021-10-14 10:54:26 Browse Times:742 Amount Downloads:1

Voip and SIP are often used interchangeably by users in the world of telephony now,but they are not the same in fact.SIP’s purpose is to initiate,maintain and terminate multimedia communication sessions in voice over IP(VOIP) applications. SIP is one of the most popular ways of implementing or delivering VoIP service to consumers, households, enterprises and other entities.VoIP is a much broader term that can be applied to any form of voice calls that happens over the Internet.

The Definition Of SIP

As stated above, SIP is one of the most common protocols used to deliver VoIP services. It is an IETF standard that was first introduced in the 90s and it continues to evolve today. To visualize the relationship between SIP and VoIP, take the example of Internet or email. These are pretty universal services used by practically every person and organization today.

Email is commonly implemented through SMTP – Simple Mail Transfer Protocol. By Implementing the services through universally accepted and standardized protocols, end users are able to send email or surf the web without barriers. For instance, a Gmail user can send email to an Outlook user or a Yahoo user or an enterprise user in much the same way. It doesn’t matter if the person is using a standalone desktop client or a webmail dashboard.

This is pretty much how SIP and VoIP are related and work. When an organization utilizes SIP to deploy their VoIP network, it is easy for other entities to work with the same equipment. For instance if the business purchases new SIP phones, they are already compatible with the network because they use the same protocol.

The Relationship Between SIP Aand VOIP

SIP is a text based protocol that was developed on a similar model to HTTP responses. When compared to alternatives such as H.323, it is very simple to construct and debug. But it is also extremely flexible and has powerful features that can be utilized in very complex PBX systems. It is a general-purpose protocol that can handle a variety of sessions. In VoIP specifically, SIP is used to perform a variety of functions including:

User registration

SIP endpoints – basically your telephones – register themselves with proxy servers that maintain lists of individual endpoint locations. When a particular phone initiates a call, the request is sent to the proxy server which then contacts the other endpoint to set up the session.

User availability

SIP determines if the various parties are available to answer the call or participate in the session. It means that different endpoints can set up rules stating when or how they would like to be contacted and when they are available for calls. For instance, a particular phone may not accept calls from 8 AM to 5 PM or will only accept calls from within the same network etc.

User capabilities

The various endpoints involved in a particular session use SIP to determine what kind of audio codecs and other media capabilities (video, file transfer etc.) can be utilized in the call.

Session set up

SIP tells the phone that is being called to start ‘ringing’ and manages the initial contact between all parties.

Session management

SIP also performs other management functions such as ending the call, adding another caller, switching to video conferencing etc.

What is the purpose of SIP in VoIP?

SIP is not the only protocol that can be used for implementing VoIP, there are plenty of others like H.323. At present however, very few organizations and equipment manufacturers implement VoIP on other protocols. SIP has become the defining standard and universally accepted protocol for VoIP. How did this happen? There are several reasons for this development.

Even though SIP is used for voice communication, it was not developed by or within the telecommunications industry. Instead it is an IP-based protocol that is maintained by the IETF which is the Internet Engineering Task Force. SIP is flexible and because it has its roots in the IT industry, is much more capable of being integrated with other Internet applications, software and systems. Thus it is highly suitable to the way businesses function in today’s world, rather than being a relic of telecom systems from the last century.

Organizations do not need to hire telecommunication experts for VoIP deployments. It is a simple text based protocol and similar to HTTP. This means that many IT professionals can immediately become familiar with SIP as they have been working with HTTP for many years. Since VoIP essentially treats voice calls as simply a form of data, enterprise deployments are generally managed and maintained by the IT department itself.

In addition to this, it is an open source protocol and has been developed to ensure interoperability from the beginning. Manufacturers of VoIP equipment frequently test SIP compatibility before launching their products. For all the above reasons SIP has gained significant traction and is now the first choice for any organization wishing to deploy VoIP networks.

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