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www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
Right-Size Your IP-PBX
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
Agenda
What we will cover
• Define “Right-Sizing”• Telephony Past and
Present• Sample Planning
Methodology• Key Considerations
– 5 - W’s– Architectures
What we will not cover
• Specific Vendor Implementations
• Feature Details• Protocol Wars
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
Right-Sizing Defined
• Right-Sizing is the careful planning, consideration and implementation of a VoIP solution that meets current capacity requirements and allows for simplified expansion for future needs while taking into account the necessary endpoint and feature bandwidth requirements.
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
Why is this a concern?
• Legacy PBX solutions have fixed capacities based on card-based technology.
In other words, you can’t add more than 16 stations to a 16-port card.
• IP-PBX solutions are not always constrained by port counts on cards so the limiting factor is most often the bandwidth on the connecting link; be it LAN, WAN, WIFI, satellite, or cellular.
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
The Past
Each phone plugged directly into the legacy switch. When the card was full, you had to add another card; when the switch was filled to capacity, you bought a new phone system
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
Today – Enterprise Wide Scalability
VoIP ManagerVoIP Manager
BranchHubBranchHub
PSTN
PSTN
AnalogAnalogDevicesDevices
(Desktop, Fax, (Desktop, Fax, Conference,Conference,
Modem)Modem)
Facility 1Facility 1
VoIP ManagerVoIP Manager
AnalogAnalogDevicesDevices
Facility 2Facility 2
PSTN
Facility 3Facility 3
SOHOSOHO
LegacyPBX
Multi-mediaMulti-mediaCommunicationCommunication
DesktopsDesktops
T1/E1/PRI
T1/E1/PRI
Analog FXO Trunks
Analog FXO Trunks
IPIPTelephonesTelephones
(Vmail, Email(Vmail, EmailUnified Messaging)Unified Messaging)
WANWAN
IPIPTelephonesTelephones
IP TelephonesIP Telephones
IP IntegratedIP IntegratedDesktopDesktop
VoiceVoiceMessagingMessaging
MeetingHubMeetingHubCOHubCOHub
Mobile UserMobile User
VoIP ManagerVoIP Manager
COHubCOHub
PhoneHubPhoneHub
IP Connectivity (Ethernet or WAN)IP Connectivity (Ethernet or WAN)
Digital Trunks (T1, E1, ISDN PRI)Digital Trunks (T1, E1, ISDN PRI)
Analog Lines (PSTN or Stations)Analog Lines (PSTN or Stations)
* requires private network * requires private network connectivity via, typically via a VPN connectivity via, typically via a VPN connectionconnection
Key: Key:
PSTN
AnalogAnalogFXO GatewaysFXO Gateways
(IP Conference Hub)(IP Conference Hub)
Internet*Internet*
IP WiFiIP WiFiTelephonesTelephones
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
Discovery Review Design OrderReview
Adopt a Adopt a Methodology for Methodology for Planning Your Planning Your
Solution for Today, Solution for Today, Tomorrow, and Next Tomorrow, and Next
Year.Year.
Comprehensive Planning
ReviewStage CutoverReview
Planning Methodology (DDOSC)
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
Important Planning Considerations
• Ethernet switch type, capacity and manageability.• What are your bandwidth limitations.• How much bandwidth will be allocated to voice.• Is the bandwidth dedicated on a separate physical
network or is it on a logical VLAN• How will you provide Quality of Service (QoS)• Which codecs will be used and where.• Total Number of Endpoints• Additional feature requirements (Video, IM, etc.)• How will the phones receive power? Through a wall
jack at each location or via a Power over Ethernet (PoE) capable switch
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
Quick Definitions
QoS – Quality of Service - refers to the probability of the telecommunication network meeting a given traffic contract, or in many cases is used informally to refer to the probability of a packet succeeding in passing between two points in the network within its desired latency period.
vLAN – Virtual LAN - is a method of creating independent logical networks within a physical network. Several VLANs can co-exist within such a network. The advantages of a vLAN are:
• Reduces the broadcast domain, which in turn reduces network traffic and increases network security (both of which are hampered in case of single large broadcast domain)
• Reduces management effort to create subnetworks • Reduces hardware requirement, as networks can be logically instead of physically separated • Increases control over multiple traffic types • Increases network security
PoE – Power over Ethernet - describes a system to transmit electrical power, along with data, to remote devices over standard twisted-pair cable in an Ethernet network. The common standard is known as IEEE 802.3af although some vendors have proprietary power over ethernet technology.
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
Codec Defined
• A portmanteau of “coder-decoder” which describes a device or program capable of performing transformations on a data stream or signal.
• Codecs are used to convert an analog voice signal to digitally encoded version. Codecs vary in the sound quality, the bandwidth required, the computational requirements, etc.
• Each service, program, phone, gateway, etc typically supports several different codecs, and when talking to each other, negotiate which codec they will use.
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
Common Codecs
• GIPS Family - 13.3 Kbps and up • GSM - 13 Kbps (full rate), 20ms frame size • iLBC - 15Kbps,20ms frame size: 13.3 Kbps, 30ms frame size • ITU G.711 - 64 Kbps, sample-based Also known as Toll Quality • ITU G.722 - 48/56/64 Kbps • ITU G.723.1 - 5.3/6.3 Kbps, 30ms frame size • ITU G.726 - 16/24/32/40 Kbps • ITU G.728 - 16 Kbps • ITU G.729 - 8 Kbps, 10ms frame size • Speex - 2.15 to 44.2 Kbps • LPC10 - 2.5 Kbps • DoD CELP - 4.8 Kbps
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
Bandwidth Calculation Considerations
• When calculating bandwidth requirements per call, you must also factor in overhead for the IP and UDP headers.
• For example, G.711 has a bitrate of 64Kbps but a nominal IP bandwidth requirement of 80Kbps per call. The extra 16Kbps per call results from IP overhead.
• Finally, When calculating bandwidth, one can't assume that every channel is used all the time. Normal conversation includes a lot of silence, which often means no packets are sent at all. So even if one voice call sets up two 64 Kbit RTP streams over UDP over IP over Ethernet (which adds overhead), the full bandwidth is not used at all times.
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
Other Important Considerations
• When calculating bandwidth requirements and allocations make sure to take into account all variables of the link
– Is it a dedicated link?– How much bandwidth will be allocated to voice?– What other applications are running?– Will you employ silence suppression?
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
Why Should You Consider VoIP?
•Your Legacy PBX is obsolete, too costly to service, or out of capacity.
•Continued investment results in a stranded asset, not fully depreciable.
•You have a high concentration of “knowledge” workers that can benefit from the increased productivity realized from “enhanced services”.
•You are rapidly expanding and a converged solution is easier to deploy, maintain and grow.
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
Where Should You Implement VoIP?
•Which employees would benefit the most? knowledge workers, executives, call center agents?
•What locations are the best fit? Remote offices, HQ, new offices?
•Which networks are capable? All LAN’s, most LAN’s, WAN connected remote offices?
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
When Should You Deploy VoIP?
•What is the appropriate sense of urgency?•Is there an immediate problem that can be solved? •Can you start by “extending the life” of your current system?•How can you leverage this opportunity to begin positioning for your future needs?
•If possible, develop a phased approach over 6, 12, 18 months.
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
What Are Your Best Applications for VoIP?
•Should you replace all legacy systems with VoIP?•Can you continue to leverage VoIP to extend the life of your existing system? If so, how will that solution allow you to expand easily and cost effectively.
•Can the VoIP platform start small and easily grow to meet my longer term needs? If so how and at what cost?
•Can you utilize a “best-of-breed” approach to the solution? Phones, Call control, Voicemail from different providers?
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
Which Vendor(s) Can Best Meet Your Needs?
•Experienced with Voice applications or Data Applications?
•Open solutions vs Closed solutions?•Multi-Vendor Components vs Single Vendor Components ?
•Application focused vs Network focused?
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
IP PBX Deployment Scenarios
Technology EvaluationTechnology Evaluation Proactive IntroductionProactive Introduction Full Scale AdoptionFull Scale AdoptionExploratoryExploratory Cap and GrowCap and Grow GreenfieldGreenfield
• Proactive evaluation of the technology and capabilities.
• Limited reach within the organization initially.
• Controlled roll out.• Minimize capital
expenditures.
• Cap investments in legacy solutions.
• Selective introduce capabilities to targeted users.
• Solve practical business needs.
• Understand the larger picture and potential.
•Lowest Risk•Ensures readiness for the
future•May represent throw away
investment
•Balanced Approach•Manages obsolescence
effectively•Does not realize full
benefits•Expansion may be a
challenge
•Full benefits are realized•Best ROI
•Greatest change•Greatest Risk
• Deploy IP at all new locations.
• Replace legacy systems.• Mandate use of
enhanced services.• Actively pursue
productivity advantages.
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
IP PBX Approaches
Extended LifeExtended Life TDM over IPTDM over IP Purpose Built IPPurpose Built IPIP EnabledIP Enabled HybridHybrid Client ServerClient Server
• Ideal for extending the life of a Legacy PBX
• Often used for tie line migration to IP
• Lowers TDM Trunk costs
• Ideal for small scale systems (<100 stations)
• Dependant on embedded call processing modules
• Redundancy is a challenge
• Most scalable approach• Most flexible approach – can also
be used as a legacy PBX migration strategy
• Greatest amount of change
PSTNIP
WAN
IPLAN
LegacyTDM PBXIP
Tru
nks
MediaGateway
PSTNIP
WAN
IPLAN
MediaGateway
TelecomServers
PSTNIP
WAN
IP Trunks
IPStations
TDM Trunks
Telecom ServerAnalogStations
IP LAN
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
Evolving VoIP TelecommunicationsAlternative Approaches
Software Centric
Network Agnostic
Open Standards Oriented System
Flat / Distributed Architecture
N + 1 Redundancy
Simple Configuration
Bundled Features
Add-on Upgrades for Expansion
Many Endpoints and Application
Best of Breed Options
Costs Less
Hardware Centric
Proprietary Networks
Proprietary / Closed Systems
Hierarchical / Centralized Architecture
N times 2 Redundancy – if any
Complex Configuration
Expensive Add-on Features
Forklift Upgrades for Expansion
Limited Endpoints & Applications
Single Vendor Solution
Costs More
Hybrid Approach Client Server Approach
www.itexpo.com
October 10-13, 2006• San Diego Convention Center, San Diego California
Summary
• Start NOW, even if modestly. The sooner you gain exposure and experience the better. Do not let your organization be caught by surprise.
• Try to anticipate the future. Make sure the solution fits your needs not only today, but tomorrow as well.
• Understand your migration path. Avoid forklift upgrades when you expand.