network architectures for a multi-service broadband internet
DESCRIPTION
Network Architectures for a Multi-Service Broadband Internet. George Clapp 973-829-4610 [email protected] Monday, September 8, 2014. Growth in the Number of Hosts NetSizer. http://www.netsizer.com/daily/table.html. Worldwide Business-to-Business E-Commerce. - PowerPoint PPT PresentationTRANSCRIPT
Network Architectures for a Multi-Service Broadband Internet
George [email protected], April 21, 2023
Multi-Service Broadband Internet Architectures – 2
Growth in the Number of HostsNetSizer
40
45
50
55
60
65
70
75F
eb-9
9
Mar
-99
Apr
-99
May
-99
Jun-
99
Jul-9
9
Aug
-99
Sep
-99
Oct
-99
Nov
-99
Dec
-99
Jan-
00
Date
Ho
st C
ou
nt
(mil
lio
ns)
http://www.netsizer.com/daily/table.html
Multi-Service Broadband Internet Architectures – 3
Worldwide Business-to-Business E-Commerce
GartnerGroupJanuary 26, 2000http://gartner12.gartnerweb.com/public/static/aboutgg/pressrel/pr012600c.html
7% of $105T total global sales transactions
0.145 0.4030.953
2.18
3.95
7.29
0
1
2
3
4
5
6
7
8
1998 2000 2002 2004
$ (t
rilli
on
s)
Multi-Service Broadband Internet Architectures – 4
Multi-Service Broadband Internet Architectures – 5
Access to the Internet
http://www.stanford.edu/dept/news/report/news/february16/internetsurvey-216.html
Stanford Institute of Quantitative Study of Society– Polled 4,113 individuals; 2,689 households
Multi-Service Broadband Internet Architectures – 6
Increasing Use with Time
http://www.stanford.edu/dept/news/report/news/february16/internetsurvey-216.html
Multi-Service Broadband Internet Architectures – 7
Generational Differences in Use of the Internet
Multi-Service Broadband Internet Architectures – 8
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
19
93
19
94
19
95
19
96
19
97
19
98
19
99
20
00
20
01
20
02
20
03
20
04
Link
Wheat, First, ...
Yankee
Jupiter
Kagan
Average
Market Demand for Internet/Online ServicesP
erc
en
tag
e o
f U
S H
ou
seh
old
s
Multi-Service Broadband Internet Architectures – 9
Market Demand for High Speed Access
Total BBD + ISDN Market
ADSL (Bellcore)
Cable Modems (Kagan)
ISDN BRI (IDC 98)
0
5
10
15
20
25
1997 1998 1999 2000 2001 2002 2003 2004
Mill
ion
s o
f H
igh
Sp
ee
d U
sers
Multi-Service Broadband Internet Architectures – 10
Source: IDC/Link 9/98
ForecastsOne View
Multi-Service Broadband Internet Architectures – 11
Simplistic but true
2000
2001 2002 2003 2004 2005
Data
Voice
0
5
10
15
20
25
30
35
2000 2001 2002 2003 2004 2005
Voice
Data
Traffic Growth RatesVoice grows at 3% per year; data grows at 100% per year
Multi-Service Broadband Internet Architectures – 12
Parts of a Network
Othercarriers
Premises Access Metropolitan
Operations
Backbone(long-haul)
Transmission
Switching
Multi-Service Broadband Internet Architectures – 13
Access Networks
AccessMultiplexer(s)
Wireless
Voice Switch
POTS (Plain Old Telephone Service)
Digital Subscriber Line (DSL) xDSLxDSL
Modem
Fiber in the loop (FITL)Fiber to the X (FTTx)
Optical Network Unit (ONU)
Hybrid Fiber Coax (HFC)
HUB
ONU
Multi-Service Broadband Internet Architectures – 14
Cable Networks
Headend
PrimaryHub
PrimaryHub
PrimaryHub
SecondaryHub
SecondaryHub
Node
Node
Few hundred thousand homes passed
Node
Node
Few tens of thousands homes passed
Few hundred to thousand homes passed
Info
rmatio
n
Multi-Service Broadband Internet Architectures – 15
http://www.webproforum.com/hfc_dwdm/
Cable NetworksAnother View with Neighborhoods
Multi-Service Broadband Internet Architectures – 16
PSTN Gateway
PacketCable Architecture
CableModem
MTA
CableModem
MTA
HFC access network
HFC access network
CMTS
CMTS
Call Management Server (CMS)
Announcement Server
OSSBack OfficeServers and Applications
Media Gateway (MG)
Signaling Gateway
MG Controller
PSTN
ManagedIP Network
PSTN: Public Switched Telephone NetworkCMTS: Cable Modem Termination SystemMTA: Multimedia Terminal Adapter
Multi-Service Broadband Internet Architectures – 17
Cable Distribution Network
V
CMTS
PSTN Gateway
HFC
MTA
CMTS
HFC
MTA
PSTN
Head End
Multimedia Cable Network Systems (MCNS)Data over Cable System Interface Specifications (DOCSIS)
Multi-Service Broadband Internet Architectures – 18
Cable Voice over IP Architecture
CiscoCisco
IP Network ILEC/PTOV
HFC Network
VoIP Infrastructure
VoIPTrunking Gateway
GigaBit Switch RoutersPacket Over Sonet
IntegratedCMTS/HeadEnd Router
CPECable Modem
Multi-Service Broadband Internet Architectures – 19
Cable Voice over IP Architecture cont’d
V
GSR12008GSR12008 OC-12
OC-12
VVV
Public TelephoneNetwork
Cat8500
TRUNKGATEWAYS
CMTS/HEADEND ROUTER
CAMPUSSWITCH ROUTER
BACKBONEROUTERS
AS5300
uBR7246
Cat8500
Optical Nodes
Multi-Service Broadband Internet Architectures – 20
Typical HFC Frequency Plan
750,860 MHz,1 GHz
5 MHz 42 MHz 550 MHz54 MHz
Ch 78
Upstream Downstream
2-way servicesDigital Video
AM Video2-way services
Ch2
320 Kbps to 10 Mbps
30 to 40 Mbps/6 MHz channel
Upstream and downstream data channels are shared
Multi-Service Broadband Internet Architectures – 21
DSLAM: Digital Subscriber Line Access Multiplexer
ADSL
Asymmetric Digital Subscriber Line
ATMSwitchFabric
Class 5Switch
To ISPs,IXCs
ADSL Modem
Data Rate(Mbps)
Wire Gauge(AWG)
Distance (ft)
1.5–2.0 24 18,0001.5–2.0 26 15,000
6.1 24 12,0006.1 26 9,000
Multi-Service Broadband Internet Architectures – 22
ADSL Access
http://www.3com.com/solutions/dsl/dsl_tech_microwt.html#_Toc389638794
Multi-Service Broadband Internet Architectures – 23
Differences between ADSL and HFC
ADSL is dedicated point-to-point technology
ADSL peak rate is 6 Mbps downstream; average rate is typically 1-2 Mbps
ADSL upstream rates are typically 1/10 of downstream
Cable modem is a shared bus (typically 100 customers)
Cable modem peak rate is 30-40 Mbps shared over all customers currently active
Cable modem systems typically have a single shared upstream channel at lower rate
Multi-Service Broadband Internet Architectures – 24
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
Types of xDSL
Multi-Service Broadband Internet Architectures – 25
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 – 26
Working Length - All RBOCs
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.5 1 1.5 2 2.5 3 3.5 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18kilofeet
All
Urban
Suburban
Rural
Total Loop Length National Segmentation
41% Urban 50% Suburban 9% Rural
Multi-Service Broadband Internet Architectures – 27
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
0%
5%
10%
15%
20%
25%
30%
35%
40%
Pe
rce
nt
of
tota
l lin
es
Am
erit
ech
Be
ll A
tlan
tic
Be
llSo
uth
GT
E
NY
NE
X
Pa
cific
Te
lesi
s
So
uth
we
ste
rnB
ell
U S
WE
ST
Na
tion
al T
ota
l
Fiber fed DLC
Copper fed DLC
1998 DLC Deployment
Multi-Service Broadband Internet Architectures – 28
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 – 29
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
Spectral Compatibility
Multi-Service Broadband Internet Architectures – 30
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 – 31
Emergence of “Double-Bubble” Networks
IP Network
Gateway Gateway
PSTN
Incumbent Local Exchange Carriers (ILECs) build out a separate IP network
Multi-Service Broadband Internet Architectures – 32
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 – 33
New Options in Protocol Stacks
WDM Optical NetworkWDM Optical Network
SONET/SDHSONET/SDH SONET/SDHSONET/SDH ATMATM IPIP
IPIP
ATMATM IPIP IPIP
Physical Fiber PlantPhysical Fiber Plant
Multi-Service Broadband Internet Architectures – 34
ATMSwitch
DWDM as Capacity Expansion
SONET ADM
SONETADM
SONET ADM
SONET ADM
WDM
WDM
IP Router
IP Router
ATM uplink on OC-3c
OC-48
OC-48
ATM uplink on OC-3c
OC-48
OC-48
OC-3c
OC-3c
ADM: Add Drop Multiplexer
Multi-Service Broadband Internet Architectures – 35
Elimination of SONET
WDM
WDM
ATMSwitch
IP Router
IP Router
ATM uplink on OC-48
ATM uplink on OC-48 OC-48
OC-48
Multi-Service Broadband Internet Architectures – 36
Revisiting Cable Networks with DWDM
http://www.webproforum.com/hfc_dwdm/index.html
Multi-Service Broadband Internet Architectures – 37
NMS(s)NMS(s)
WDM
WDM
WDM
WDM
WDMEMSWDMEMS
IPRouter
IPRouter
Internet
IPRouter
IPRouter
CableAccess
Cable
Cable Modem
IPRouter
IPRouter
IPRouter
IPRouter
IPEMSIP
EMS
Backbone IP Network
Multi-Service Broadband Internet Architectures – 38
Target Internet Backbone Architecture
WDMWDM
RoutersRouters ServersServers
Multi-Service Broadband Internet Architectures – 39
The Quality of Service ChallengeTransmission of voice through data networks
Delay
Jitter
Losses
150 msec one way delay Minimum jitter buffer of 15 msec 1-2% packet loss
Multi-Service Broadband Internet Architectures – 40
The rising tide:a first answer to the quality concern
0.1
1
10
100
1000
1983 1987 1991 1995 1999 2003
Tra
ns
mis
sio
n R
ate
(k
b/s
)
Historical modem speeds
"Moore's Law" prediction
Multi-Service Broadband Internet Architectures – 41
The delays are already almost acceptablebut there are wide variations
0%
2%
4%
6%
8%
10%
12%
14%
16%
020
040
060
080
010
0012
0014
0016
0018
0020
00
TCP connection delays (ms)
Multi-Service Broadband Internet Architectures – 42
Congestion happens!
•Loss of transmission resource
•Olympic games, earth-quake, TV show...
Multi-Service Broadband Internet Architectures – 43
Diffserv and Edge Control:Solving the QoS challenge
Managed IP backbone
Edge router
Customer
Multi-Service Broadband Internet Architectures – 44
Evolution of the NetworkTwo options for quality of service
1: Rising tide 2: Retooling
Diffserv
Ban
dw
idth
Multi-Service Broadband Internet Architectures – 45
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 – 46
Separation of traffic with priority classesVoice > Data
Multi-Service Broadband Internet Architectures – 47
Conclusion
Continued exponential growth in size and functionality of the Internet
Thanks for fiber optics, network technology is keeping pace with demand