Digital subscriber line access multiplexer (DSLAM) · PDF...
Transcript of Digital subscriber line access multiplexer (DSLAM) · PDF...
Digital subscriber line access multiplexer (DSLAM)
: http://el.wikipedia.org
Digital Subscriber Line Access Multiplexer (DSLAM) /
DSL (Digital Subscriber Line).
,
, (-Y
Kabelverteiler KV), .
XDSL Connectivity Diagram
DSLAMs ATM
(Asynchronous Transfer Mode) 2005
Ethernet IP-DSLAM.
To DSLAM DSL
ADSL G.shdsl VDSL. DSLAMs
ITU-T G.992.1 ( G.DMT) ADSL 25,875
KHz (6x4,3125) 1104 KHz (256x4,3125) 25,875-138 ( 6-31)KHz
modem DSLAM
138-1104 KHz ( 32-255) DSLAM modem.
splitters
. O Splitter 3
, , modem
. O splitter
ADSL DSLAM
DC
.
splitter .
http://el.wikipedia.org/wiki/Digital_Subscriber_Linehttp://el.wikipedia.org/wiki/2005http://el.wikipedia.org/wiki/Ethernethttp://el.wikipedia.org/wiki/ADSLhttp://el.wikipedia.org/wiki/VDSLhttp://el.wikipedia.org/wiki/%CE%A0%CF%85%CE%BA%CE%BD%CF%89%CF%84%CE%AE%CF%82http://el.wikipedia.org/wiki/%CE%A3%CF%85%CE%BD%CE%B5%CF%87%CE%AD%CF%82_%CF%81%CE%B5%CF%8D%CE%BC%CE%B1http://el.wikipedia.org/wiki/%CE%A4%CE%B7%CE%BB%CE%AD%CF%86%CF%89%CE%BD%CE%BF
ADSL ISDN Annex B
upstream 32-63x4,3125 KHz (138-271,6875 KHz) 64-255
(276-1104 KHz) downstream.
1,1 Mb/s Modem
DSLAM (upstream) 8 Mb/s DSLAM modem (downstream).
downstream
Downstream upstream.
ADSL G.shdsl
2312 Kb/s (2304 ) G.shdsl.bis 5696 Kb/s
,
. G.shdsl
.
ADSL ADSL2 ADSL2+
2208 KHz (512 x 4,3125) downstream
24 Mb/s.
VDSL2
VDSL2 DSL bandplans
,
.
.
30 MHz (3479 tones x 8,625 KHz) 100
Mb/s downstream 100 Mb/s upstream,
17,664 MHz (4096 tones x 4,3125 KHz) 100
Mb/s downstream 50 Mb/s upstream. VDSL2
25,875 8832 KHz ADSL2+ .
ADSL/2/2+ ATM '
Permanent Virtual Circuits (PVC) modems.
ATM cell Ethernet IP ( mode
http://el.wikipedia.org/wiki/Modem
).
Voice over IP
web browsing ftp. VDSL2
' VDSL2
Ethernet IP
VDSL2. PVCs
PVC Voice over IP
data PVC.
DSL
DOCSIS
. DSL
(Kb/s). DSLAM
. DSLAM 1000
ADSL2+ 10 Mb/s
10 Gb/s 1 Gb/s
1 10.
.
DSLAM
DSLAM 1999
. 2003
ATM DSLAMs Siemens Intracom.
Alcatel ZTE IP DSLAMs
2006 Huawei. DSL Vivodi
Cisco DSLAM Ericsson, Forthnet
Alcatel, Tellas Ericsson Alcatel,
Zhone, ON Telecom Marconi/Ericcson, Teledom,
NetOne, Hellas Online iBAS DSLAM Intracom Telecom.
DSL
ADSL
bitstream wholesale ISPs
PVC
VoIP IPTV
( VoIP ). ISPs
(
) ( )
DSLAMs
QoS o wholesale bitestream.
(shared
Local Loop Unbundling Line Sharing),
(full Local Loop Unbundling).
http://el.wikipedia.org/wiki/%CE%91%CE%BC%CE%B5%CF%81%CE%B9%CE%BA%CE%AEhttp://el.wikipedia.org/wiki/%CE%9F%CE%A4%CE%95http://el.wikipedia.org/wiki/1999http://el.wikipedia.org/wiki/%CE%91%CE%B8%CE%AE%CE%BD%CE%B1http://el.wikipedia.org/wiki/%CE%98%CE%B5%CF%83%CF%83%CE%B1%CE%BB%CE%BF%CE%BD%CE%AF%CE%BA%CE%B7http://el.wikipedia.org/wiki/%CE%94%CE%B9%CE%B1%CE%B4%CE%AF%CE%BA%CF%84%CF%85%CE%BF
K DSLAM modems
DSLAMs (
) Huawei, ZTE, - UTStarcom -
Alcatel Lucent, - Nokia Siemens, ZyXEL
Loop Telecom, Teledata Networks ECI Telecom, NEC
Fujitsu, KeyMile, Iskratel, Corecess,
Calix, Allied Telesyn, Adtran, Motorola Tellabs Intracom Telecom.
modems s
hardware
S/W.
DSL chipsets
chipsets Broadcom Ikanos (
2009 Broadband Business Unit Conexant spin-off
Mindspeed GlobespanVirata
Globespan Virata). Analog Devices
chipsets modems. Ikanos DSL Business Division
Centillium Lantiq broadband division Infineon (
Siemens Microelectronics).
SGS-Thomson (ST) division
Alcatel Microelectronics, Freescale (spin-off) Motorola, Texas Instruments
Business Division Infineon.
DSL Amati Communications Corporation " DSL"
Stanford University John Cioffi Aware Executive Chairman .
.
Bandwidth versus distance
Balanced pair cable has higher attenuation at higher frequencies. Therefore, the longer the wire
between DSLAM and subscriber, the slower the maximum possible data rate due to the lower
frequencies being utilized to limit the total attenuation (or due to the higher number of errors at
higher frequencies, effectively lowering the overall frequency/data rate). The following is a
rough guide to the relation between wire distance (based on 0.40 mm copper and ADSL2+
technology) and maximum data rate. Local conditions may vary, especially beyond 2 km, often
necessitating a closer DSLAM to bring acceptable bandwidths:
25 Mbit/s at 1,000 feet (~300 m)
24 Mbit/s at 2,000 feet (~600 m)
23 Mbit/s at 3,000 feet (~900 m)
22 Mbit/s at 4,000 feet (~1.2 km)
21 Mbit/s at 5,000 feet (~1.5 km)
19 Mbit/s at 6,000 feet (~1.8 km)
16 Mbit/s at 7,000 feet (~2.1 km)
8 Mbit/s at 10,000 feet (~3 km)
1.5 Mbit/s at 15,000 feet (4.5 km)
800 kbit/s at 17,000 feet (~5.2 km)
http://el.wikipedia.org/wiki/%CE%A4%CF%83%CE%B9%CF%80%CF%83%CE%B5%CF%84http://el.wikipedia.org/wiki/2009http://en.wikipedia.org/wiki/Attenuationhttp://en.wikipedia.org/wiki/Asymmetric_Digital_Subscriber_Line_2_Plus