Transcript NGN Architectures

Network Architectures for a
Multi-Service Broadband Internet
George Clapp
973-829-4610
[email protected]
Wednesday, April 6, 2016
Growth in the Number of Hosts
NetSizer
70
65
60
55
50
45
Jan-00
Dec-99
Nov-99
Oct-99
Sep-99
Aug-99
Jul-99
Jun-99
May-99
Apr-99
Mar-99
40
Feb-99
Host Count (millions)
75
Date
http://www.netsizer.com/daily/table.html
Multi-Service Broadband Internet Architectures – 2
Worldwide Business-to-Business E-Commerce
7.29
8
$ (trillions)
7
6
5
3.95
4
2.18
3
2
1
0.145
0.403
0.953
0
1998
2000
2002
2004
7% of $105T total global sales transactions
GartnerGroup
January 26, 2000
http://gartner12.gartnerweb.com/public/static/aboutgg/pressrel/pr012600c.html
Multi-Service Broadband Internet Architectures – 3
Multi-Service Broadband Internet Architectures – 4
Access to the Internet
 Stanford Institute of Quantitative Study of Society
– Polled 4,113 individuals; 2,689 households
http://www.stanford.edu/dept/news/report/news/february16/internetsurvey-216.html
Multi-Service Broadband Internet Architectures – 5
Increasing Use with Time
http://www.stanford.edu/dept/news/report/news/february16/internetsurvey-216.html
Multi-Service Broadband Internet Architectures – 6
Generational Differences in Use of the Internet
Multi-Service Broadband Internet Architectures – 7
Market Demand for Internet/Online Services
40%
35%
Link
30%
Wheat, First, ...
25%
Yankee
20%
Jupiter
15%
Kagan
10%
Average
5%
2004
2003
2002
2001
2000
1999
1998
1997
1996
1995
1994
0%
1993
Percentage of US Households
45%
Multi-Service Broadband Internet Architectures – 8
Market Demand for High Speed Access
Millions of High Speed Users
25
20
15
Total BBD + ISDN Market
ADSL (Bellcore)
Cable Modems (Kagan)
10
ISDN BRI (IDC 98)
5
0
1997
1998
1999
2000
2001
2002
2003
2004
Multi-Service Broadband Internet Architectures – 9
Forecasts
One View
Source: IDC/Link 9/98
Multi-Service Broadband Internet Architectures – 10
Traffic Growth Rates
Voice grows at 3% per year; data grows at 100%
per year
35
30
25
20
Voice
15
Data
10
5
0
2000
2001
2002
2003
2004
2005
2000
2001
2002
Voice
2003
2004
2005
Simplistic but true
Data
Multi-Service Broadband Internet Architectures – 11
Parts of a Network
Operations
Premises Access
Metropolitan
Other
carriers
Backbone
(long-haul)
Switching
Transmission
Multi-Service Broadband Internet Architectures – 12
Access Networks
Hybrid Fiber Coax
(HFC)
Digital Subscriber
Line (DSL)
Fiber in the loop (FITL)
Fiber to the X (FTTx)
Optical Network
Unit (ONU)
HUB
xDSL
Modem
xDSL
ONU
Access
Multiplexer(s)
Wireless
Voice Switch
POTS (Plain Old Telephone Service)
Multi-Service Broadband Internet Architectures – 13
Cable Networks
Few hundred
thousand homes
passed
Primary
Hub
Information
Head
end
Primary
Hub
Primary
Hub
Few tens of
thousands homes
passed
Secondary
Hub
Secondary
Hub
Node
Node
Node
Node
Few hundred to
thousand homes
passed
Multi-Service Broadband Internet Architectures – 14
Cable Networks
Another View with Neighborhoods
http://www.webproforum.com/hfc_dwdm/
Multi-Service Broadband Internet Architectures – 15
PacketCable Architecture
MTA
Cable
Modem
PSTN
HFC access
network
CMTS
Media Gateway (MG)
Call Management
Server (CMS)
Managed
IP Network
Announcement
Server
MG Controller
PSTN Gateway
HFC access
network
MTA
Signaling Gateway
CMTS
Cable
Modem
PSTN: Public Switched Telephone Network
CMTS: Cable Modem Termination System
MTA:
Multimedia Terminal Adapter
OSS
Back Office
Servers and
Applications
Multi-Service Broadband Internet Architectures – 16
Multimedia Cable Network Systems (MCNS)
Data over Cable System Interface Specifications
(DOCSIS)
Cable Distribution Network
PSTN Gateway
CMTS
CMTS
PSTN
V
Head End
HFC
HFC
MTA
MTA
Multi-Service Broadband Internet Architectures – 17
Cable Voice over IP Architecture
VoIP Infrastructure
Cisco
HFC
Network
ILEC/PTO
IP Network
V
CPE
Cable Modem
GigaBit Switch Routers
Packet Over Sonet
Integrated
CMTS/HeadEnd Router
VoIP
Trunking Gateway
Multi-Service Broadband Internet Architectures – 18
Cable Voice over IP Architecture cont’d
GSR12008
GSR12008
Cat8500
Cat8500
AS5300
CMTS/
HEADEND ROUTER
BACKBONE
ROUTERS
V
V
V
V
CAMPUS
SWITCH ROUTER
TRUNK
GATEWAYS
uBR7246
Public Telephone
Network
Optical Nodes
Multi-Service Broadband Internet Architectures – 19
Typical HFC Frequency Plan
Upstream
Downstream
Ch
2
5 MHz
Ch
78
42 MHz 54 MHz
2-way services
320 Kbps to
10 Mbps
550 MHz
AM Video
750,860 MHz,
1 GHz
Digital
Video
2-way services
30 to 40 Mbps/6 MHz channel
 Upstream and downstream data channels are shared
Multi-Service Broadband Internet Architectures – 20
Asymmetric Digital Subscriber Line
DSLAM: Digital Subscriber Line
Access Multiplexer
ADSL
Modem
ATM
Switch
Fabric
ADS
L
To ISPs,
IXCs
Class 5
Switch
Data Rate
(Mbps)
1.5–2.0
1.5–2.0
6.1
6.1
Wire Gauge
(AWG)
24
26
24
26
Distance (ft)
18,000
15,000
12,000
9,000
Multi-Service Broadband Internet Architectures – 21
ADSL Access
http://www.3com.com/solutions/dsl/dsl_tech_microwt.html#_Toc389638794
Multi-Service Broadband Internet Architectures – 22
Differences between ADSL and HFC
 ADSL is dedicated point-to-point
technology
 Cable modem is a shared bus
(typically 100 customers)
 ADSL peak rate is 6 Mbps
downstream; average rate is
typically 1-2 Mbps
 Cable modem peak rate is 30-40
Mbps shared over all customers
currently active
 ADSL upstream rates are typically  Cable modem systems typically
1/10 of downstream
have a single shared upstream
channel at lower rate
Multi-Service Broadband Internet Architectures – 23
Types of xDSL
 ADSL
– Downstream: 1 Mbps to 8 Mbps
– Upstream: 128 kbps to 640 kbps
– Range: 12 kft to 18 kft
 G.lite
– Downstream: 1.5 Mbps
– Upstream: 512 kbps
– Range: 18 kft
 VDSL
–
–
–
–
Downstream: 13 Mbps to 52 Mbps
Upstream: 1 Mbps to 4 Mbps
Range: 1 kft to 4 kft
For use off of DLC RDT or FTTC ONU
 IDSL
–
–
–
–
Downstream: 128 kbps
Upstream: 128 kbps
Range: 18 kft
No POTS
 HDSL
–
–
–
–
–
–
Downstream: 1.544/2.048 Mbps
Upstream: 1.544/2.048 Mbps
Range: 12 kft
Requires Two Pair
Used for commercial T1/E1 service
Taking the majority (70% of U.S. in
1996) market for T1s
 SDSL (One Pair HDSL)
–
–
–
–
Downstream: 784 kbps
Upstream: 784 kbps
Range: 12 kft
No POTS
Multi-Service Broadband Internet Architectures – 24
Limitations and Obstacles to xDSL
 Distance limited, Maximum loop length dependent on
– Data rate
– Gauge makeup
 Bridged Tap
 Load Coils
 Noise
 Crosstalk
 Serving Arrangement - Copper vs. DLC
Multi-Service Broadband Internet Architectures – 25
Total Loop Length
 National Segmentation
41% Urban
50% Suburban
9% Rural
Working Length - All RBOCs
100%
All
90%
Urban
Suburban
80%
Rural
70%
60%
50%
40%
30%
20%
10%
0%
0.5
1
1.5
2
2.5
3
3.5
4
5
6
7
8
kilofeet
9
10
11
12
13
14
15
16
17
18
Multi-Service Broadband Internet Architectures – 26
Digital Loop Carrier
 Digital Loop Carrier (DLC) Solution Needed
– Over 20% of US loops served by DLC
– Much higher in some regions of the country
– Majority of new growth served by DLC
– Many of the affluent, suburban, prime ADSL subscriber
neighborhoods served by DLC
1998 DLC Deployment
35%
30%
25%
20%
Fiber fed DLC
Copper fed DLC
15%
10%
National Total
U S WEST
Pacific Telesis
NYNEX
GTE
BellSouth
Bell Atlantic
0%
Southwestern
Bell
5%
Ameritech
Percent of total lines
40%
Multi-Service Broadband Internet Architectures – 27
National Loop Statistics
 Load Coils
– Approximately 2% - 8% of all loops are loaded
– xDSL will not operate over loaded lines
 Bridged Tap
– Approximately 70%-80% of all loops have one or more Bridged Tap
– Bridged Tap are generally not a problem.
– Lowers SNR by a few dB resulting in small decrease in range
– Bridged-tap at or very close to the Quarter-wavelength length may
cause more problems
Multi-Service Broadband Internet Architectures – 28
Spectral Compatibility
 T1 lines and ADSL
– Near End Cross Talk (NEXT) from T1 can nearly stop downstream ADSL
– NEXT from ADSL can disrupt T1
 Repeatered HDSL and ADSL
– HDSL repeaters can destroy ADSL on long loops.
 ADSL and VDSL
– NEXT from ADSL can significantly hurt VDSL signals
 Unbundling xDSL, and different CLECs
– May cause incompatibilities between various flavors of xDSL
Multi-Service Broadband Internet Architectures – 29
Summary
 xDSL allows LECs to deploy high speed data services quickly
and economically over their existing infrastructure
 At the same time, the xDSL addressable market is constrained
by the existing infrastructure
 Loop Qualification is a necessity
 DLC solutions are necessary to unlock more potential
subscribers
Multi-Service Broadband Internet Architectures – 30
Emergence of “Double-Bubble” Networks
PSTN
Gateway
Gateway
IP Network
Incumbent Local Exchange Carriers (ILECs) build out a separate IP network
Multi-Service Broadband Internet Architectures – 31
Dense Wave Division Multiplexing
 Multiplex wavelengths into a single optical fiber
 Lucent WaveStar OLS 400G supports up to 80 optical channels
of 2.5 Gb/s each over a single fiber
http://www.webproforum.com/dwdm/topic01.html
Multi-Service Broadband Internet Architectures – 32
New Options in Protocol Stacks
IP
ATM
IP
IP
SONET/SDH
SONET/SDH
ATM
IP
WDM Optical Network
Physical Fiber Plant
Multi-Service Broadband Internet Architectures – 33
DWDM as Capacity Expansion
ATM uplink on OC-3c
OC-3c
IP Router
SONET
ADM
W
D
M
ATM uplink on OC-3c
IP Router
SONET
ADM
OC-48
OC-48
OC-48
SONET
ADM
W
D
M
ATM
Switch
OC-48
SONET
ADM
OC-3c
ADM: Add Drop Multiplexer
Multi-Service Broadband Internet Architectures – 34
Elimination of SONET
ATM uplink on OC-48
OC-48
IP Router
W
D
M
W
D
M
ATM
Switch
IP Router
ATM uplink on OC-48
OC-48
Multi-Service Broadband Internet Architectures – 35
Revisiting Cable Networks with DWDM
http://www.webproforum.com/hfc_dwdm/index.html
Multi-Service Broadband Internet Architectures – 36
Backbone IP Network
NMS(s)
Cable Modem
IP
EMS
IP
Router
Cable
WDM
EMS
Internet
IP
Router
WDM
Cable
Access
IP
Router
WDM
WDM
WDM
IP
Router
Multi-Service Broadband Internet Architectures – 37
Target Internet Backbone Architecture
Routers
Servers
WDM
Multi-Service Broadband Internet Architectures – 38
The Quality of Service Challenge
Transmission of voice through data networks
Delay
Losses
Jitter
 150 msec one way delay
 Minimum jitter buffer of 15 msec
 1-2% packet loss
Multi-Service Broadband Internet Architectures – 39
The rising tide:
a first answer to the quality concern
Transmission Rate (kb/s)
Historical modem speeds
"Moore's Law" prediction
1000
100
10
1
0.1
1983
1987
1991
1995
1999
2003
Multi-Service Broadband Internet Architectures – 40
The delays are already almost acceptable
but there are wide variations
00
20
00
18
00
16
00
14
00
12
00
10
0
80
0
60
0
40
0
20
0
16%
14%
12%
10%
8%
6%
4%
2%
0%
TCP connection delays (ms)
Multi-Service Broadband Internet Architectures – 41
Congestion happens!
• Loss of transmission resource
• Olympic games, earth-quake, TV show...
Multi-Service Broadband Internet Architectures – 42
Diffserv and Edge Control:
Solving the QoS challenge
Managed IP
backbone
Edge
router
Customer
Multi-Service Broadband Internet Architectures – 43
Bandwidth
Evolution of the Network
Two options for quality of service
1: Rising tide
Diffserv
2: Retooling
Multi-Service Broadband Internet Architectures – 44
Different Requirements for Voice and Data
 Voice
– Sensitive to delay and jitter
– Low tolerance for packet loss
 Data
– Delay insensitive
– Packet loss dramatically reduces throughput
 Small buffers
– VoIP delays lie within acceptable bounds; compliance with loss
bounds are ensured only for low loads of TCP traffic
– Severe degradation of TCP performance even at very low loads
since the buffers are unable to accept even small bursts that are
generated by a TCP flow
 Large buffers
– Good throughput for TCP
– VoIP traffic suffers a sharp increase in jitter at even moderate buffer
sizes
Multi-Service Broadband Internet Architectures – 45
Separation of traffic with priority classes
Voice > Data
Multi-Service Broadband Internet Architectures – 46
Conclusion
 Continued exponential growth in size and functionality of the
Internet
 Thanks for fiber optics, network technology is keeping pace with
demand
Multi-Service Broadband Internet Architectures – 47