Transcript Document

3.2. Evolution of access networks’ technologies to
broadband
A. Reference structure of access network
NT - Network Termination
CPE - Customer Premises Equipment
AN – Access Node
TP – Twisted pair
FOC – Fiber optic
PL – Power line
CPE
Access Network
Core Network
TP/Coax/Radio/FO/PL
NT
CPE
AN
•High cost of access networks 50-70% of the total cost of local telephone networks
•Modems/ISDN, LL (E1) based on four-wire connection
B. Access networks go to broadband
Local networks based on outdated principles are became a “bottleneck”,
limiting subscriber’s access to modern services.
Key forces:
• New subscriber’s requirements to providing new services
• New regulations
• Development of new services in voice, data and video information in
interactive and broadcasting mode
# WWW pages with powerful video information
# Multimedia applications Digital Video Broadcasting (DVB), Video-on-Demand (VoD), interactive TV
• Emergence of alternative operators in local networks, who compete with
incumbent operators in provisioning a wide set of additional services
• Construction of high-speed core networks with a capacity of dozens and
hundreds of Gbit/s
• Wireless Technologies
Technology Trends
•
•
•
•
Data communications exceed telephony
Wireless/mobile subscribers exceed landline subscribers
Broadband on Wireless
Emergence of the Next Generation Networks
Business growing the broadband access
Grow the market in three waves:
– High-speed Internet access (HSIA)
– Business access (start with underserved SOHO segment)
– Residential multimedia (gaming/video/entertainment)
Address new audiences (PC, TV, console)
Residential Multimedia
Build on existing infrastructure
Move
aggressively
into HSIA
Today
Business Access
High-speed Internet access
TIME
C. Different media to the customer
Satellites / Sky Stations
GSM/GPRS/UMTS
WLAN
Optical Fiber
Twisted Pair
Cable/Coax
Access Network
Backbone
Networks
Technological limitations of different
transmission media
Limits of Transmission Media
Mbit/s
Transmission Capacity [Mbit/s]
10000
1000
Fiber
250
100
Cellular
Wireless*
Coax
10
1
Copper Twisted Pair
0,1
0,1
1
10
100
Distance [km ]
*Capacity in Mbit/s/qkm, Bandwidth 500 MHz
Optical fibers are the only alternative at high bandwidth and distances
D. Access networks’ technologies
time
UMTS
2010
2005
SHDSL
UDSL
2000
HDSL
HSCSD
VDSL
GPRS
SDSL
2B1Q
VoD
TV digital Voice
4B3T
POTS
TV
DECT
WLAN
xDSL
TV analog
GSM
PDC
CDMA
CDMA
VSAT
ISDN
1990
EDGE
PMP
ADSL
1995 Power line
BPON
WLL
Satellite
OPAL
Bluetooth
AMPS
Cellular radio
1980
Copper
Coax Wireless
1975
Copper
1900
Fiber optics
PON
STM 1
AON
E. Broadband access with xDSL technologies
Extending high bit rates coverage
ADSL+
10 Mb/s
7.5 Mb/s
Bit rates
5.5 Mb/s
ADSL
3.5 Mb/s
1 Mb/s
Increasing loop length
CPE
Central
Office
DSLAM
# 63.8 m DSL lines worldwide at end of 2003
Source: DSL Forum, 2004
# 'Top Ten' DSL countries by number of lines
Source: DSL Forum, 2004
# 'Top Ten' countries per 100 population
Source: DSL Forum, 2004
F. Broadband access in CATV network
TS
CPh
POTS
Hub
TV
TV
Coax
Hub
Coax or
Fiber
Headend
STB
PC
CM
Internet
TV Studio
TS - Telephone set
CPh - Cable phone
STB - Set-top box
CM - Cable modem
POTS - Plain old telephone system
Cable modems
•
•
•
•
Access to the Internet provided by operators in CATV networks –
Due to new regulations for CATV operators Key factor of cable modem applications
New application of cable modems – HBR access to Internet
# 3 Mbit/s in symmetrical configurations
# 30 Mbit/s in forward and 10Mbit/s in backwards directions in asymmetrical
configurations
Other most important services in CATV networks
# Distribution of digital TV programs
# Interactive digital television
# Voice over IP and Voice over ATM
New possibilities of broadband access via cable modems –
due to an evolution of AN Coax infrastructure to HFC infrastructure
G. Broadband Wireless Access
General term – Wireless Local Loop (WLL)
G1. Fixed BWA (LMDS/MMDS/PtM…) for fixed wireless
access
LMDS - Local Multipoint Distribution System
MMDS - Microwave Multipoint Distribution System
•Interactive television TV with related services
•Voice service (usually as supplement to other services)
•High-speed data transmission for business users
•Access to the Internet and streaming multimedia from Web sites
G2. Mobile BWA (WLAN, UMTS, IMT-2000…)
WLAN Standards:
IEEE 802.11, 802.11a, 802.11b and 802.11g
802.11b - Wi-Fi ("wireless fidelity") technology
Wi-Fi - alternative to a wired LAN (offices/homes)
•Ethernet protocol & CSMA/CA (carrier sense multiple access with collision
avoidance) for common channel sharing
•Frequency range - 2.4 GHz
•Data speeds - up to 11 Mbps
•802.11a
BRs from
1
D
100
•802.11b
1
100
11 Mb/s
50 m
•802.11g
1
100
54 Mb/s
20 m
to 12 Mb/s
50 m
G.3. WiMax – Worldwide Interoperability
for Microwave Access
•Most fundamental difference between Wi-Fi and WiMax – they are
designed for totally different apps
•Wi-Fi is LAN technology designed to add mobility to wired LANs.
•WiMax was designed to provide MAN BWA services
•Wi-Fi supports a transmission up to few hundred meters, WiMax could
support services in area up to 50 km
Source: dBrn Associates, Inc., 2004
WiMax Cell
Beyond 3G vision
H. Comparison How long
does it take
to download:
E-mail
Song or photo
1 h video
MP 3
MPEG 4 in TV-Quality
High resolution
Wireless
wired
3k
3M
300 M
GSM
9,6 k
2,5 sec
42
min
3 days
PSTN
56 k
0,4 sec
7
min
12 hours
GPRS
ISDN
115 k
128 k
0,2 sec
3,5 min
6 hours
UMTS
ADSL
2M
8M
0,01 sec
Cable
WLAN
30 M
80 M
1
Fiber
800 G
30
12
sec
20 min
ms
1
sec
30 sec
ns
30
µsec
3 ms
Live Video Codecs starting with 32 kbit/s
Byte
bit/s
Broadband access in Europe and US
EUROPE
•
•
According to a new IDC study, broadband penetration in Western Europe will continue to surge
in coming years. By 2009, 46% of Western European households will have broadband access,
compared to 20% at the end of 2004. By 2009, there will be more than 92 million broadband
connections, up from 40 million at the end of 2004. 83% of these will be provided to the
residential market.
Although Internet access will remain the most important application for the short to medium
term, services like voice over broadband and IPTV will be cornerstones of successful business
strategy.
US
In 2004, the number of high-speed subscribers in the U.S. grew by 35.4% to 32.5 million
subscribers, consisting of the following access technologies:
• cable modem
- 17.0 million
• DSL
- 12.6 million
• fixed wireless
- 2.2 million
• fiber-to-the-home
- 0.2 million
• satellite
- 0.4 million
• mobile wireless (3G) - 0.1 million
• broadband over power line - less than 50,000
J. Access networks – concluding remarks
# Access networks are the most expensive part for
operators
# Copper cables have an average life span of approx. 50
years.
# Copper transmission systems reach their theoretical
limits in access networks at approx. 50 Mbit/s.
# In Europe and North America massive investments in
access networks will be realized in 10-20 years.
Most of these investments will be applied to fiber optics
and to wireless networks.