Pbx Systems For Ip Telephony / Edition 1

by Allan Sulkin

Overview

This work explains telephone switching systems and how the technology is evolving to accommodate voice-over-IP traffic. Unlike data networks, telephone networks are proprietary. They're purchased as complete systems and are hard if not impossible to modify. Allan Sulkin explains how to acquire, deploy and maintain a system with all the features needed to support essential new applications, and how to get optimal performance from the system you have.

Product Details

ISBN-13:	9780071375689
Publisher:	McGraw Hill LLC
Publication date:	04/24/2002
Series:	McGraw-Hill Telecom Series
Pages:	487
Product dimensions:	7.40(w) x 9.30(h) x 1.12(d)

About the Author

Allan Sulkin is the founder of the TEQConsult Group, which advises enterprise communications providers on product development for customer premises . He is widely acknowledged as the foremost expert in PBX (private branch exchange) and ACD (automatic call distribution) communications systems today. His clients include Cisco, Lucent, Siemens, and Nortel. Sulkin is also a columnist and seminar leader for Business Communications Review. His company has its offices in Hackensack, New Jersey.

Table of Contents

Chapter 1	Enterprise Communications Systems Today	1
	The Fundamental Enterprise Communications Systems	5
	KTS	5
	PBX	6
	Hybrid System	7
	ACD Systems	8
	Voice Messaging System	9
	Interactive Voice Response System	11
	Convergence of KTS/Hybrid and PBX Systems	11
Chapter 2	Evolution of the Digital PBX, 1975-2000	15
	Digital Switching/Transmission	17
	Computer Stored Program Control	20
	Digital Desktop	22
	Modular System Design	24
	Feature/Function Enhancements	28
	Basic Voice Call Station/System Features	28
	Data Communications	31
	Video Communications	33
	Networking	34
	ACD-based Call Centers	36
	Computer Telephony Integration (CTI)	38
	Mobile Communications	41
	Messaging	42
Chapter 3	Legacy PBX Call Processing Design	45
	Fundamentals of PBX Circuit Switching	47
	Time Division Multiplexing	47
	Pulse Code Modulation	48
	TDM Bus Bandwidth and Capacity	49
	Port-to-Port Communications over a Single TDM Bus	51
	Multiple TDM Bus Design	52
	PBX Circuit Switching Design	54
	Center Stage Switch Complex	55
	Broadband TDM Bus	56
	Single-Stage Circuit Switch Matrix	57
	Multistage Circuit Switch Matrix	58
	ATM Center Stage	59
	Local Switching Network Design: TDM Buses and Highway Buses	60
	PBX Switch Network Topologies	64
	Centralized	65
	Distributed and Dispersed Switch Network Designs	67
	PBX Switch Network Issues	71
	Switch Network Redundancy	71
	Time Slot Access and Segmentation	73
	Time Slot Availability: Blocking or Nonblocking	75
Chapter 4	Legacy PBX Switch Network Design	79
	Nonblocking/Blocking PBX Systems	80
	PBX Grade of Service (GoS)	82
	Defining PBX Traffic: CCS Rating	83
	Trunk Traffic Engineering	88
	Determining Trunk Circuit Requirements	92
Chapter 5	Legacy PBX Traffic Engineering Analysis	95
	Common Control Complex	96
	Main System Processor	98
	Operating System Platform	98
	Basic Call Processing Functions	100
	Main System Memory	103
	Local Processors	104
	Port Circuit Card Microcontrollers	104
	Cabinet/Carrier Shelf Local Controllers	105
	System Processing Bus	106
	PBX Call Processing Design Topologies	107
	Centralized Control	108
	Dispersed Control	110
	Distributed Control	111
	Call Processing Redundancy Issues	112
	PBX Call Processing Power: BHC Rating	116
Chapter 6	Legacy PBX Common Equipment	121
	System Cabinets	123
	Carrier Types	126
	Control	126
	Switching	126
	Port	127
	Auxiliary	128
	Application	128
	Power	129
	Cabinet Power System	129
	Cabinet Backplane	132
	Cabinet/Carrier Expansion Requirements	132
	Port Growth	133
	Increased Traffic Requirements	133
	Increased Call Processing Requirements	133
	New Application Requirements	133
	Printed Circuit Boards	134
	Control Cards	136
	Local Loop Interfaces: Maintenance/Diagnostic	137
	Service Cards	137
	Port Cards	139
	Circuit Card Provisioning Issues	143
	TDM Bus Time/Talk Slot Restrictions	143
	Call Processing Limitations	144
	Power Distribution Limitations	144
	Card Slot Requirements	144
Chapter 7	Introduction to IP-PBX Systems	147
	ToIP and IP-PBX Systems	150
	IP-PBX SYSTEM: Benefits and Advantages	154
	Leverage Existing Investment in LAN/WAN Infrastructure	154
	Reduce Capital, Network, and Operating Expenses	154
	Simplify System and Network Configuration Upgrades and Expansion	155
	Conforms to Standards	156
	Support of Applications across the Enterprise	156
	Availability of New and Improved Station User Features and Applications	157
	The Case for Converged IP-PBX Systems	158
	ToIP Requirements	159
	Investment Protection	160
	Critical Reliability	162
	Private Network Compatibility	163
	Feature Requirements	165
	Pricing	166
	The Case for the Client/Server IP-PBX	169
	Converged Network	170
	Universality of IP Transport	171
	Network Bandwidth	171
	Simplified Centralized Management and Administration	172
	Rapid Deployment of New Technology and Applications	172
	Fully Distributed Network Design	172
	Scalability	173
Chapter 8	VoIP Standards and Specifications	175
	ITU-T H.323	176
	Point-to-Point and Multipoint Conferencing Support	177
	Internetwork Interoperability	177
	Heterogeneous Client Capabilities	178
	Audio and Video Codecs	178
	Management and Accounting Support	178
	Security	178
	Supplementary Services	178
	H.323 Benefits	179
	H.323 Architecture Components	180
	Terminal	181
	Gateway	181
	Gatekeeper	181
	Multipoint Control Unit	182
	Border Elements	183
	H.323 Architecture Protocols and Procedures	183
	Call Signaling and Control	183
	H323 Annexes	184
	Audio Codecs	184
	Video Codecs	184
	H.323 Audio Codecs	186
	H.323 Control and Signaling Mechanisms	186
	H.225.0 RAS	188
	Gatekeeper Discovery	188
	Endpoint Registration	188
	Endpoint Location	188
	Other Communications	188
	H.225.0 Call Signaling	189
	H.245 Media Control	189
	Capability Exchange	190
	Opening and Closing of Logical Channels	190
	Flow Control Messages	190
	Other Commands and Messages	190
	The Need for RTP/RTCP	190
	Real-Time Transport Protocol	192
	RTP Payload	192
	RTP Packet	193
	RTCP Packet	193
	Real-Time Transport Control Protocol	194
	SIP	197
	SIP Call Process	199
	SIP Addressing	199
	Locating a SIP Server	200
	SIP Transaction	200
	SIP Invitation	200
	H.323 or SIP?	201
	Emerging Dominance of IP	201
	Signaling Reliability Mechanism	201
	Client/Server Design	201
	Addresses	202
	Complexity and Cost	202
	Command/Message Format	202
	QoS Management	203
	Firewall/Proxy Design and Configuration	203
	Extendible and Scalable	203
	Other Protocols: MGCP and MEGACO (H.248)	204
Chapter 9	Converged IP-PBX System Design	207
	IP Station Ports	208
	Making IP Voice Calls	214
	IP Trunk Ports	216
	Dispersed Common Equipment over LAN/WAN Infrastructure	220
	Upgraded Circuit Switched PBX	220
	Distributed Modular Design	223
Chapter 10	Client/Server IP-PBX System Design	227
	Telephony Call Server	230
	Server Operating System	232
	Server Redundancy	233
	Multifunction Server Design	239
	Telephony Gateways	242
	Summarizing Client/Server IP-PBX Design Issues	247
Chapter 11	LAN/WAN Design Guidelines for VoIP	251
	Fundamental LAN Planning Guidelines	254
	Factors Affecting QoS: Packet Loss and Latency	260
	Packet Loss	260
	Latency	262
	QoS Controls	268
	802.1p/Q	268
	ToS	269
	Differentiated Services (DiffServ)	270
	QoS Control Summary Points	271
	A Final QoS Factor: Echo	272
	TIA IP Telephony QoS Recommendations	272
Chapter 12	PBX Cabling Guidelines	277
	Cabling System Fundamentals	279
	Cable Interference and Noise Issues	281
	Overview of ANSI/TIA/EIA 568	283
	Entrance Facility	284
	Equipment Room	284
	Backbone Cabling	284
	Telecommunications Closet	285
	Horizontal Cabling	286
	Telecommunications Outlet	289
	Work Area	290
	Overview of ANSI/TIA/EIA 569	291
Chapter 13	PBX Voice Terminals	295
	Voice Terminal Categories	297
	Analog Telephones	298
	Digital Telephones	299
	IP Telephone Design Basics	303
	Distinct IP Telephony Features/Functions	305
	Desktop Voice Terminal Attributes	317
	Power Requirements	324
Chapter 14	PBX Networking	325
	Public Networking	326
	Automatic Route Selection (ARS)	326
	ISDN Features	328
	ANI/SID	329
	CBCSS	330
	Private Networking	332
	Single System PBX Network: On-net Multilocation Support	332
	Distributed PBX Common Equipment Design	335
	Remote Port Cabinet Options	337
	Multiple System Private Networking	341
	Fundamentals of PBX Private Networks	343
	Uniform Dial Plan (UDP)	344
	Automatic Alternate Routing (AAR)	345
	FRLs and Network Class of Service (NCOS)	345
	Automatic Circuit Assurance (ACA)	346
	Virtual Private Networks (VPNs)	346
	Intelligent Feature Transparent Network (IFTN)	349
	IFTN Features and Functions	351
	Qsig	354
	Qsig Architecture	356
	Qsig Supplementary Services and ANFs	356
Chapter 15	PBX Systems Management and Administration	359
	System Administration	361
	Administration Sequence	361
	Performance Management	365
	Trunk Usage and Traffic	365
	Attendant Consoles	365
	Stations	366
	Traffic Distribution	366
	Busy Hour Traffic Analysis	366
	Processor Occupancy	366
	Threshold Alarms	366
	Feature Usage	367
	VoIP Gateways	367
	CDR	367
	Directory	369
	Inventory	369
	Cabling	369
	System Diagnostics and Maintenance	369
Appendix A	Call Processing Feature/Function Glossary and Definitions	373
Appendix B	PBX/IP-PBX Cost and Pricing Issues	399
Appendix C	Client/Server IP-PBX RFP Example	407
Appendix D	PBX/IP-PBX System Feature and Function Matrices	445
	Index	469