Voice over LTE, SIP & the IMS

5 Day Course
Code PWS212

Book Now - 2 Delivery Methods Available:

Classroom Virtual Classroom Private Group - Virtual Self-Paced Online


This course is designed to give the delegate an understanding of the options for voice traffic within an LTE network. We look and describe the various options available including, CSFB, VoLTE and voice call continuity in LTE.

The course will be enhanced with call flow example and SIP session examples. We will also investigate the full working of Session Initiation Protocol (SIP) and the IP Multimedia Subsystem (IMS), together with Private & Public Addressing.


Upon completion of the course delegate will be able to:

  • Describe the various methods of supporting voice services with 3G/4G LTE
  • Describe the EPC core network and procedures
  • Understand the QoS requirements in LTE
  • Describe the IMS structure and control entities
  • Describe the Policy & Charging Rules Function
  • Explain the content of the HSS
  • Understand the Default EPS Bearer setup
  • Understand the requirement for Dedicated EPS Bearers
  • Understand IMS Service Identity Modules
  • Explain Private & Public User Identities
  • Explain an IMS Session
  • Describe Circuit Switched Fallback procedures
  • Understand VoLTE Radio Performance

Target Audience

Any engineers who are assisting in the deployment of voice services within their LTE networks, support engineers for both core and radio networks, technical managers and sales executives.


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VoLTE System Architecture (9 topics)

  • LTE Radio
  • LTE Radio Background
  • LTE Radio Architecture
  • Evolved Packet Core
  • EPC Entities & Functions
  • EPS Mobility Management
  • IMS Entities
  • Home Subscriber Server
  • Policy & Charging Rules Function

VoLTE Functionality (27 topics)

  • Radio Functionality
  • Bearers & Schedulers
  • Mobility
  • Circuit Switched Fall Back Handover
  • Mobility from 2G/3G back to LTE
  • Power Saving Features
  • Positioning Services
  • UE Radio Access Capabilities for VoLTE users
  • EPC Functionalities
  • LTE Subscriber Identification
  • PDN Connectivity Establishment
  • EPS Dedicated Bearer Setup
  • IMS Identification
  • IP Multimedia Identification Module
  • Public User Identity
  • Private User Identity
  • Relationship between Public & Private Identity
  • Identification of Users device
  • Identification of Network Entities
  • Identification of Services
  • Identification without ISIM
  • IMS Service Provisioning
  • Enforcement of Allowed Services
  • Service Triggering Information
  • Selection of the AS
  • AS Behaviour
  • Service Provisioning in Action

VoLTE End-to-End & Signalling (45 topics)

  • VoLTE Subscription & Device Configuration
  • EPS Attach for CSFB/IMS VoIP & Default Bearer
  • IMS Registration
  • Constructing the REGISTER Request
  • From the UE to the P-CSCF
  • From the P-CSCF to the I-CSCF
  • From the I-CSCF to the S-CSCF
  • S-CSCF Challenges the UE
  • UE's Response to the Challenge
  • Registration at the S-CSCF
  • The 200 OK Response
  • Third-Party Registration to Application Servers
  • Subscription to Registration Event Package
  • Re-Registration & Re-Authentication
  • De-Registration
  • Related Standards
  • IMS VoIP Session
  • Constructing the INVITE Request
  • Routing
  • Media Negotiation
  • Media Resource Reservation & Policy Control
  • Charging
  • Session Release
  • Voice Continuity
  • PS - PS Intersystem Handover
  • Single Radio Voice Call Continuity
  • IMS Emergency Session
  • PDN Connection Setup for Emergency Session
  • Emergency Registration
  • Emergency Session
  • CS Fallback for Evolved Packet System Call Case
  • Architecture of CS Fallback in EPS
  • Description of SGs Interface
  • Idle Mode Signalling Reduction
  • Idle Mode vs Active Mode
  • CS Fallback Attachment
  • Mobile Originating Call using CSFB
  • Mobile Terminating Call using CSFB
  • Call Unrelated CSFB Procedures
  • Mobile Terminating Roaming Retry & Forwarding
  • VoLTE Messaging
  • Native IMS Messages
  • SMS Interworking
  • Multimedia Messaging Service
  • Unstructured Supplementary Services Data Simulation in IMS

IMS Services (8 topics)

  • Location Services
  • Emergency Service
  • Billing Services
  • Interworking with OTT Messaging
  • Presence
  • Group Management
  • Push-to-talk-over-cellular
  • Conferencing

VoLTE Radio Performance (3 topics)

  • Coverage
  • Latency
  • Capacity

Session Initiation Protocol (SIP) & Session Description Protocol (SDP) (7 topics)

  • Introduction to SIP requests
  • SIP Responses
  • Exploring the content of the SDP message
  • The Offer/Answer Process
  • Dialogues & Sessions
  • Managing QoS
  • Using RTP/RTCP


A good understanding of the LTE network and environment would be expected as would a strong understanding of IP. Cellular technologies should already be fully understood.

Scheduled Dates

Please select from the dates below to make an enquiry or booking.


Different pricing structures are available including special offers. These include early bird, late availability, multi-place, corporate volume and self-funding rates. Please arrange a discussion with a training advisor to discover your most cost effective option.

Code Location Duration Price Apr May Jun Jul Aug Sep
Virtual Classroom (Bangalore)
5 Days $4,165
Virtual Classroom (Dubai)
5 Days $4,165
Virtual Classroom (London)
5 Days $4,165
Virtual Classroom (Reston, VA)
5 Days $4,165
Virtual Classroom (Singapore)
5 Days $4,165

What Our Customers Say

The training was delivered with a high level of expertise and excellence. Instructor was highly knowledgeable.”

Technical Trainer, Aviat Networks

Overall the course was really good, the trainer really understood the material and was very approachable.”

Customer Training Manager, Aviat Networks

Excellent course, informative and well-paced.”

CSE, Cisco

Course was very well outlined. Topics were great and bridged many gaps.”

System Engineer, Cable & Wireless

An excellent intro to video encoding & MPEG transport streams - I would definitely recommend it.”

Broadcast Engineer, Cisco

Definitely an excellent intro. Left me interested in learning more.”

Broadcast Engineer, Eircom

Excellent training course with real examples and practical classroom demonstrations.”

Transport Designer, Orange

Instructor knowledge and experience was excellent.”

Solutions Engineer, Akamai

Excellent course, very clear and well organised. Course content delivery was very good.”

Assistant Engineer, Dhiraagu

Very informative and appropriate.”

Network Support Technician, BT

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