utilization of high bandwidth channels martin weiss
TRANSCRIPT
Utilization of High Bandwidth Channels
Martin Weiss
Slide 2
Objectives of this Meeting
Describe multiplexing techniques Identify the elements of the public
telephone network Describe the organization of the
public telephone network
Slide 3
Frequency Division Multiplexing
Line 6Line 5Line 4Line 3Line 2Line 1
Time
Frequency
Guard Band
Transmission
Bandwidth
Slide 4
Time Division MultiplexingFrequency
Time1 2 3 4 5 6 1 2 3 4 5 6
Framing
Samples from Lines
Slide 5
North American Digital Multiplex Hierarchy
Common transmission rates–DS0 = 64 kbps–DS1 = 1.544 Mbps = 24 DS0's–DS3 = 44.736 Mbps = 28 DS1's = 672 DS0's
Slide 6
ITU Digital Multiplex Hierarchy
Common transmission rates–E0 = 64 kbps–E1 = 2.048 Mbps = 30 E0's–E2 = 8.448 Mbps = 120 E0's–E3 = 34.368 Mbps = 480 E0's–E4 = 139.264 Mbps = 1920 E0's–E5 = 565.148 Mbps = 7680 E0's
Slide 7
Structure of Digital Transmission - T1
Data is organized into Frames Frames are delimited by a Framing
Bit Frames of frames, called
Superframes, are also defined
Slide 8
Structure of a T1 Frame
Channel 1
Channel 2
Channel 3
Channel 24
F
Frame length–24 channels * 8 bits/channel = 192 Bits
–Add 1 framing bit = 193 Bits
Slide 9
1 2 3 4 5 6 7 8 9 101
11
2
1 1 1 1 1 10 0 0 0 00
Frame Number
Value of Framing Bit
Normal T1 Superframe Structure
Slide 10
ESF Frame Structure
Frame Number
Contents of Framing Bit
1 2 3 4 5 6 7 8 9 101
11
2
D D C 0 D CC D 0 D 1D
19
20
21
22
D D C 1 D CC D 0 D 1D
13
14
15
16
17
18
23
24
D - Data Link Bits
C - CRC-6 Bits
Slide 11
Components of a T1 Line
CSU CSU
IXC Network
USER
LEC 2 Network
LEC 1 Network
CSUUSER CSU
User's CPE
Slide 12
Structure of the Public Network
Technical structure–Telephone network structure–Equipment requirements and configuration
Organizational Structure (US)–Local access–Long distance
Slide 13
Initial Network Structure
Slide 14
Intermediate Network Structure
Central
Office
Slide 15
Expansion of the Intermediate Structure
Central
Office
Central
Office
Central
Office
Central
Office
Slide 16
Toll Offices
Central
Office
Central
Office
Central
Office
Central
Office
Toll Offic
e
Slide 17
Switching Hierarchy (Pre-Divestiture)Regional
CenterSectional
Center
Primary Center
Toll Center
Central OfficeLocal
Tandem
Office
High Usage Trunks
Slide 18
Components of the Public Network
Local Loop
Switch
Multiplexer
Switch
Multiplexer
Transmission
System
PBX
Local Loop
Trunk Lines
Signalling
Slide 19
Structure of the Public Network (1950s)
InsideWire
LocalLoop
CentralOffice
TandemOffice
Tariffed andRegulated
InterstateNetwork
State Federal
Slide 20
Structure of the Public Network (1970s)
Tariffed andRegulated
InsideWire
LocalLoop
CentralOffice
AT&T’s TandemOffice
OCC’sTandemOffice
2 wire
4 wire
PCA
InterstateNetwork
InterstateNetwork
State Federal
Slide 21
Structure of the Public Network (1980s)
Tariffed andRegulated
LocalLoop
CentralOffice
“Dominant” IXC’s POP
“Non-Dominant”IXC’s POP
4 wire
4 wire
EnhancedServiceProvider
InterLATANetwork
InterLATANetwork
State Federal
Slide 22
Structure of the Public Network (Early 1990s)
Tariffed andRegulated
LocalLoop
LECCentralOffice
“Dominant” IXC’s POP
“Non-Dominant”IXC’s POP
4 wire
4 wire
EnhancedServiceProvider
CAPs/Cable TV/Wireless
OperatorServices Providers
ToIXC
InterLATANetwork
InterLATANetwork
State
Federal
Slide 23
Structure of the Network (Late 1990s)
LocalLoop
LECCentralOffice
IXC’s POP
EnhancedServiceProvider
CAPsCATVWirelessIXC
OperatorServices Providers
ToIXC
InterLATANetwork
State
Federal
InterLATANetwork
LEC’s POP
Slide 24
Telephone Competition (1893-1912)
LocalLoop Central
OfficeTandemOffice
InterstateNetwork
LocalLoop
CentralOffice
TandemOffice
Bell System
Non-Bell Company
Local Franchise
Slide 25
Telephone Competition (1912-1921)
LocalLoop Central
OfficeTandemOffice
InterstateNetwork
LocalLoop
CentralOffice
Bell System
Non-Bell Company
Tariffed andRegulated
State
Slide 26
Signalling in the Telephone Network
Traditional signalling Modern signalling Intelligent Network services
Slide 27
Traditional Signalling Terminal to Switch Switch to Switch
Slide 28
In-Band Signalling
Signalling Path and Message Path
Slide 29
Out-of-Band Signalling
Message PathSignalling Path
Slide 30
ITU Signalling System 7 (SS7)
New generation of signalling system
More capable than SS6 (CCIS) The Integrated Services Digital
Network (ISDN) requires SS7
Slide 31
SS7 Services: The Intelligent Network
Extensive Application of SS7 Technology
Custom Local Access Subscriber Services (CLASS)
Advanced Intelligent Network Services–More sophisticated applications of IN services