Introduction to VoIP
Traditional voice and data networks
- The Public Switched Telephone Network
- Packet-switched data networks
- OSI and IETF reference models
Realizing the benefits of VoIP
- Using data networks to transmit voice and video traffic
- Taking advantage of new communications features available with SIP and H.323
Applying VoIP Fundamentals
Defining multimedia conferences
- Voice, video, data and mixed conversions
- Key VoIP hardware and software components
- Gateways and gatekeepers
- Signaling & data protocols
Deploying H.323 or SIP within your organization
- SIP vs. H.323
- Configuring and testing SIP IP PBX and IP phones
- Setting up voice and video conferencing
- Creating ring groups for a call center
- Tuning network quality-of-service for user satisfaction
Analyzing H.323 and SIP calls
- Capturing SIP and H.323 signaling exchanges
- Implementing and analyzing silence suppression
- In-depth analysis of SIP signaling messages
- Registering with a gatekeeper or proxy
- RTCP messages
Leverage SIP for Seamless Communication
Building the IP infrastructure
- Packetizing voice for carriage through the IP network with RTP
- Employing reliable signaling with TCP
- Maintaining real-time voice performance with RTP
Analyzing VoIP signaling
- Distinguishing between SIP, H.323, H.225 and H.245
- Applying SDP to SIP packets
- Call setup and teardown
Addressing within VoIP networks
- Mapping phone numbers to IP addresses
- Gatekeepers, proxies, locations and call servers
Measuring voice quality
- Mean opinion scores (MOS)
- Detecting flaws in transmitted voice
- Grade of service and capacity planning
| Voice Quality Engineering
Classifying factors that affect voice quality
- Encoding voice effectively
- Comparing codecs
- Assessing the effects of delay and loss on quality
Selecting the best codec
- G.711, G.722, G.723, G.726, G.729
- Testing for differences in performance
- Adaptive techniques
- Voice companding: µ-law, A-law
Open and multivendor systems
- Anatomy of IP phones
- Open source Asterisk IP PBX
- Gateways to the PSTN legacy phone network
Capacity planning for voice over packet
- Determining bandwidth needs
- Comparing LAN and WAN performance
- Assessing the impact on data networks
Designing Networks to Carry VoIP
Calculating bandwidth service requirements
- Traffic engineering
- Measuring sporadicity of signals
- Sizing service loading for multisite operation
- Designing VoIP service: case study
Minimizing delay and delay variation
- Calculating queuing delays
- Sizing link capacity needs and required trunk speeds
- Calculating expected routing delays
- Controlling admission in commercial services
- Employing Random Early Discard (RED)
- Designing for high availability
Delivering Quality on Real Networks
Exploiting the Internet with VoIP services
- Making calls with IP phones over the Internet
- Providing international voice services
- Linking a call center to the Internet
- Adding VoIP to an e-commerce Web site
Employing quality services on intranets
- Resource Reservation Protocol (RSVP)
- Configuring IP precedence
- Multiprotocol Label Switching (MPLS)
- Observing the effects of data traffic and fair queuing on voice services
- Mixing voice and data traffic effectively
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