SIP is a Signaling Protocol

SIP is a Signaling Protocol

spscom.com

SIP as an Enabling

Technology

SIP and VoIP Fundamentals

Mike Taylor - CTO

Strategic Products and Services

888.777.7280

/

300 Littleton Road

/

Parsippany, NJ 07054

Agenda

What is SIP?

Acceptance of SIP

SIP Economics?

Leveraging SIP for Mobility

SIP and Business Continuity

What is Session

Initiation

Protocol?

Text Based Signaling Protocol –

IETF 3261

Think HTTP

Signaling for Voice, Video, IM/Chat or ….

Separate from Media

SS7

Media

ISDN SIP

The more it changes the more it stays the same!

4

SIP is a

Signaling

Protocol

SIP is the “language” that devices speak to set up phone calls (or other types of communications) between devices.

After the call is set up, the device uses Real

Time Protocol (RTP) for the talk path (just like H.323)

SIP uses English (people can read it) messages to communicate between endpoints.

This is good and bad. Security concerns.

SIP is not proprietary – it is developed as an industry standard protocol!

SIP vs. H.323

Both of these protocols are IEEE industry standard signaling protocols

They are not proprietary

H.323

Mature protocol that can support a large set of call control features

SIP

Is maturing and call control features are currently being added

Does not yet support the full set of call control features as is in H.323 today

Has the promise of much more because this protocol has the potential to do much more

5

SIP vs. H.323

These are simply signaling protocols with

IEEE RFC documents that describe the details of the protocol spec

The specific method of SIP implementation is up to the provider of the product being used

In general, each SIP implementation will be a little different

Most SIP termination devices will have

“Adaption Modules” to account for these differences

H.323 is a more mature protocol where most of the interoperability issues have been resolved

6

Why is

SIP so

Important?

SIP is being adopted by EVERYONE as the industry standard signaling protocol.

This includes Avaya, Microsoft, Cisco,

WorldCom, AT&T, CommWorks, Google,

Lucent and Yahoo!

7

8

5 Building

Blocks of SIP

User Agents

Network Servers

SIP Messages

Session Description Protocol

Gateways and SBCs

9

SIP

Components

User Agent Client

(UAC) : It generates requests and send the request to servers - typically Proxies or Registrars

User Agent Server

(UAS) : It gets requests, processes those requests and generate responses.

Back-To-Back User Agent

(B2BUA) : Both

UAC and UAS

A UA can be either a UAS or UAC dependent on which UA initiated the request for the media session. It is also possible that a UA could be operating as both a UAS and UAC especially during a three-way call or call transfer.

10

SIP User

Agents

User agents (UAs) are applications installed on SIP endpoints such as an IP phone, mobile phone, wireless device , or a laptop / desktop PC that interface between the user and the SIP network.

SIP UAC/UAS

SIP UAC/UAS

SIP Network

Servers

Network servers provide:

Registrar and Location services

Routing (Proxy or Redirect)

Presences Services

Servers in the network allow easy session establishment!

11

SIP Network Server

12

REGISTER

INFO

SIP Method

SIP Messages

Simple Yet

Powerful

SIP Method

INVITE

Description

Invites a user to a call

ACK

BYE

Used to facilitate reliable message exchange for

INVITEs

Terminates a connection between users or declines a call

CANCEL

OPTIONS

Terminates a request, or search, for a user

Solicits information about a server's capabilities

Registers a user's current location

Used for mid-session signaling

Description

SIP UAC/UAS

SIP

Network

Server

SIP UAC/UAS

Session

Description

Protocol

(SDP)

SDP is used for

multimedia

session announcement, invitation and other forms session initiation

SDP determines following additional information:

Bandwidth

Contact info for the person responsible for the media type

Transport protocol

Media format

Multicast address and Transport Port for media.

Remote address for media / Transport port for contact address.

Once the SIP session is built, SDP adds multimedia

14

Gateways and

Session Border

Controllers

SIP Gateways

Provide protocol translation and interoperability with non-SIP system elements such as:

TDM

H.323, and

PSTN

Session Border Controllers (SBCs)

Provide robust security and management by:

Allowing SIP communications to transition enterprise firewalls

Solving NAT traversal issues

As firewalls, preventing unauthorized access to and from an enterprise network.

SIP Simplifies Networks

A Single Pipe to the Cloud

Phones

Phones

LAN

LAN

PBX

Router

IP Data/Telephony

Internal Communications

PBX

TDM

External Communications

TDM

External Communications

Router

IP Data/Telephony

All Communications

PSTN Long

Distance

PSTN Local

Access

• VoIP for internal communications only

• Separate TDM interfaces required for external communications with partners/suppliers/customers

• Extra cost, extra hardware, extra complexity

IP

Network

VoIP Today

SIP Trunking

PSTN Long

Distance

Service

Provider

SIP

Network

• Single IP link for voice/data

• Eliminate PSTN interfaces for longdistance and local access

• Save 20%+ on toll charges

• Prepare for future SIP solutions

PSTN Local

Access

SIP

An ecosystem that broadens your app universe!

Adaptable

For different users, needs,

• industries

Simple to use and deploy

Contextual

How and where you work

Business process integration

Inclusive Architecture

Leverage “best in class” apps from across solution providers

Multi-Modal

Speech, mobile devices, PCs, phones

Video, Web 2.0, collaboration, kiosks

ACCEPTANCE OF SIP

SIP Disaggregates Voice Networks

Runs on TCP, UDP or SCT protocols

More cost effective that IP

Can carry rich UC to interconnect applications more effectively

300

250

200

150

100

50

0

Worldwide SIP Trunking Line Penetration, 2008-2015:

Comparison of May 2008 and December 2009 Forecast

Line Centric

Voice Calls

Administered

Individual Routing

2008 2009 2010 2011 2012 2013 2014 2015

December 2009 Forecast

May 2008 Forecast

Source: IDC

User Centric

Multimedia Sessions

User Control

Centralized Policy

SIP ECONOMICS

Better Manageability

SIP is easy to learn, develop, troubleshoot and support

Modeled after HTTP, easier to understand and interpret

Single network for all communications

Enhanced scalability

From single road warrior to small branch to carrierclass enterprise solutions with common applications and user experience

Lower Communications and Business Costs

Cost saving SIP trunking

Reduced PBX hardware

Minimize travel with collaborative applications

Leverage multimodal communications to eliminate the costs of delayed decision making

Reduce cost of real estate and optimize geographic coverage with a more mobile workforce

Administrative Savings – In English

Easy to Troubleshoot and Understand

BEFORE

PRI-based Architecture:

Capacity managed site-by site

Each site requires sufficient headroom

Small sites have dramatic under-utilization

SIP Trunking Setting the Stage:

Voice as an Application

AFTER

SIP-based Architecture:

Underutilized PRIs from multiple vendors are collapsed onto a single handoff using a shared pool of concurrent call paths

Case Study

Example: 1,250 Seat Organization

5:1 User-to-SIP Trunk drives 250 sessions

(11) T1 equivalent

$4,050 savings per month

$57.60 per channel month for PRI

$41.40 per channel month for SIP

$16.2 savings per month x 300 channels

Gartner report: http://www.gartner.com/id=1378124

250 Session Mediant 4000

MSRP at $19,750

SIP can also Reduce Hardware Costs

Reduce

HARDWARE components

Reduce

FOOTPRINT requirements

Reduce

POWER consumption

And this is not even using a high density gateway!

Before

8 full racks of equipment…

Times of Change – Savings!

After

3 racks of equipment

Think of the hardware savings

…energy savings

…space savings

…power savings

…maintenance contracts

…T1 management reduction

Disaster

Recovery

Location A

SIP traffic is data and can be re-routed. This includes DID numbers!

Do not necessarily have double the trunks to provide a 100% back up, just the access pipe

Carrier

Location B

Integration

Native Mobility

A single SIP Address Of Record (AOR) provides a unifying public address for all communications

SIP intelligence allows simultaneous or sequential “ringing” to all devices

End-point Flexibility

Seamless integration of desk phones, video devices, soft clients or mobile phones and devices

Eliminate the complexity of multiple networks

Simplify business processes

Unprecedented Interoperability

Open, IETF Standard based

Active working groups (SIPit, SIPconnect, SIP Forum)

Wide applications eco-system

Productivity

Presence

Understand availability and communication preferences before initiating communications

Enhanced Constituent Service

Speed first call resolution in the contact center through ability to leverage available experts and use side-bar communication channels

Faster decision making improves responsiveness to customers

Improved ability to reach the right employee drives customer satisfaction

Improved Employee Productivity

Integrate communications into business processes

Maximize workforce effectiveness regardless of location

What Can

Presence Look

Like?

Enterprise

Session Border

Controller

Enterprise

Session Manager

Active

Enterprise

IP-PBX Core

Carrier

SIP

SBC

Enterprise

Session Border

Controller

Enterprise

Session Manager

Active

Enterprise

IP-PBX Backup

Typical SIP Architecture

Remote Worker

Or

Mobile Device

Session Border Controller

Security

SIP Normalization

Demarcation

Session Manager

SIP Registrar

Session Management

Application Integration

Dial Plan

Routing

How do You Realize the Savings from SIP?

Avaya AuraTM Savings

Estimator

Sales Engineering

Solution Architecture

Services

Financial Monitoring

Services

SIP Economic

Assessment Service

Business & Technical

Planning Services

Implementation

Services

1

Current State Discovery &

Analysis

Current State Discovery &

Analysis

Example Deliverable:

IT Network Diagram

You can easily find anything in your IT Infrastructure with complete Drill-Down Details

Example Deliverable: SIP Payback

Optimize payback by using SIP in 2 ways:

1.

Internal SIP (Migrating Voice traffic to the Data Network)

2.

External SIP (Connectivity to the PSTN)

All options yield a positive return but a combined view accelerates the return in less than 2 years

QUESTIONS?

Thank You

spscom.com

Strategic Products and Services

888.777.7280

/

300 Littleton Road

/

Parsippany, NJ 07054

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