tecnologÍas de red avanzadas – master ic 2009-2010 – tema 1: redes de acceso a internet. ...
TRANSCRIPT
TECNOLOGÍAS DE RED AVANZADAS – Master IC 2009-2010 – http://www.grc.upv.es/docencia/tra/
Tema 1: Redes de acceso a Internet.Tema 1: Redes de acceso a Internet.
Estructura de Internet MPLS
Tecnologías cableadas Digital Subscriber Line (xDSL) Cable Broadband Service Broadband Over Power Lines Fiber
Tecnologías inalámbricas Satellite Wireless 3G
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A “nuts and bolts” view of a network
Millions of connected computing devices: hosts, end-systems pc’s workstations, servers PDA’s phones, toasters
running network apps communication links
fiber, copper, radio, satellite routers: forward packets
(chunks) of data thru network protocols: control sending,
receiving of msgs TCP, IP, and HTTP, FTP, PPP,
…
2
local ISP
companynetwork
regional ISP
router workstation
servermobile
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A closer look at the network structure
1. The network edge: applications and hosts
2. The network core: routers network of networks
3. The access networks and physical media: communication links
3
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4
Internet structure: network of networks
Roughly hierarchical National/international
backbone providers (NBPs) e.g. BBN/GTE, Sprint, AT&T,
IBM, UUNet interconnect (peer) with
each other privately, or at public Network Access Point (NAPs)
A point of presence (POP) is a machine that is connected to the Internet.
Internet Service Providers (ISPs) provide dial-up or direct access to POPs. regional ISPs
connect into NBPs local ISP, company
connect into regional ISPs
NBP A
NBP B
NAP NAP
regional ISP
regional ISP
localISP
localISP
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Network Access Points (NAPs)
5Source: Boardwatch.com
Note: Peers in this context are commercial backbones.
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MCI/WorldCom/UUNET Global Backbone
6Source: Boardwatch.com
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The situation in Europe
7
See: http://www.redes.upv.es/ralir/en/MforS/GEANT2.WMVAlso: http://video.google.com/googleplayer.swf?docId=-4949195951027294198&hl=en-GBMore about technolgies: http://video.google.com/googleplayer.swf?docId=-4634094763983277329&hl=en-GB
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Hierarchical Routing
aggregate routers into regions, “autonomous systems” (AS)
routers in same AS run same routing protocol“intra-AS” routing protocolrouters in different AS can run different intra-AS routing
protocolGateway router
Direct link to router in another AS
4-8
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4-9
3b
1d
3a
1c2aAS3
AS1
AS21a
2c2b
1b
Intra-ASRouting algorithm
Inter-ASRouting algorithm
Forwardingtable
3c
Interconnected ASes
forwarding table configured by both intra- and inter-AS routing algorithmintra-AS sets entries
for internal destsinter-AS & intra-As
sets entries for external dests
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Intra-AS Routing
also known as Interior Gateway Protocols (IGP)most common Intra-AS routing protocols:
RIP: Routing Information Protocol
OSPF: Open Shortest Path First
IGRP: Interior Gateway Routing Protocol (Cisco proprietary)
4-10
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Internet inter-AS routing: BGP
BGP (Border Gateway Protocol): the de facto standard
BGP provides each AS a means to:Obtain subnet reachability information from neighboring
ASs.Propagate reachability information to all AS-internal
routers.Determine “good” routes to subnets based on
reachability information and policy.allows subnet to advertise its existence to rest of
Internet: “I am here”
4-11
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Why MPLS?
Integrate best of Layer 2 and Layer 3- Intelligence of IP Routing- performance of high-
speed switching- Legacy service transport- QoS- VPN Semantics- Link layers include:
- Ethernet, PoS, ATM, FR
Note: MPLS and IP could be optimal solution for overall IP Services Architecture.
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0MPLS as a Foundation for Value Added
Services
VPNsVPNs
MPLSMPLS
Traffic Engineering
Traffic Engineering IP+ATMIP+ATM
Network InfrastructureNetwork Infrastructure
IP+OpticalGMPLS
IP+OpticalGMPLS
Any Transport Over MPLS
Any Transport Over MPLS
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General Context
• In Core:Forward using labels (as opposed to IP addr)Label indicates service class and destination
Label Switch Router (LSR)
Label Distribution Protocol (LDP/TDP,RSVP,BGP)
Edge Label Switch Router
• At Edge (ingress):Classify packetsLabel them
• At Edge (egress):Remove Label
(PE) – Provider Edge
(P) – Provider
(CE) – Customer Edge
(PE) – Provider Edge
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Control and Forward Plane Separation
LFIB
Routing Process
MPLS Process
RIB
LIB
FIB
Route
Updates/
Adjacency
Label Bind
Updates/
Adjacency
IP TrafficMPLS Traffic
Control Plane
Data Plane
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MPLS Example: Routing Information
128.89
1
01
0
Routing Updates (OSPF, EIGRP, …)
You Can Reach 128.89 and 171.69 Thru Me
You Can Reach 171.69 Thru Me
You Can Reach 171.69 Thru Me
You Can Reach 128.89 Thru Me
You Can Reach 128.89 Thru Me
In Label
Address Prefix
128.89
171.69
1
1
OutI’face
OutLabel
In Label
Address Prefix
128.89
171.69
0
1
OutI’face
OutLabel
In Label
Address Prefix
128.89 0
OutI’face
OutLabel
… … … … … …
171.69
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MPLS Example: Assigning Labels
128.89
1
01
0
Label Distribution Protocol (LDP)
(downstream allocation)
Use Label 4 for 128.89 and
Use Label 5 for 171.69
Use Label 4 for 128.89 and
Use Label 5 for 171.69
Use Label 7 for 171.69Use Label 7 for 171.69
In Label
Address Prefix
128.89
171.69
1
1
OutI’face
OutLabel
In Label
Address Prefix
128.89
171.69
0
1
OutI’face
OutLabel
In Label
Address Prefix
128.89 0
OutI’face
OutLabel
-9
… … … … … …… …… … … …
9
7
4
5
4
5
-
-
171.69
Use Label 9 for 128.89Use Label 9 for 128.89
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In Label
Address Prefix
128.89128.89171.69
1
1
OutI’face
OutLabel
… …… …
4
5
-
-
MPLS Example: Forwarding Packets
Label Switch Forwards Based on Label
In Label
Address Prefix
128.89
171.69
0
1
OutI’face
OutLabel
… …… …
9
7
445
In Label
Address Prefix
128.89 0
OutI’face
OutLabel
-9
… …… …
Data 128.89.25.4 Data
128.89.25.4 Data
128.89
1
01
0
128.89.25.4128.89.25.4 44
99
MPLS network egress point
128.89.25.4 Data
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Un ejemplo: ONO
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Un ejemplo: ONO
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Un ejemplo: ONO
TECNOLOGÍAS DE RED AVANZADAS – Master IC 2009-2010 – http://www.grc.upv.es/docencia/tra/
time
1900
1975
2010
1980
1990
1995
2000
2005
Copper
Fiber optics
Wireless
CoaxCopper
WLLSatellite Cellular
radio
DECT
AMPS
GSMPDC
CDMA
GPRSHSCSD
EDGE
PON AON
OPAL
BPON
TV analog
Voice
VoD
TV digital
ISDN
4B3T
2B1Q
xDSL
HDSL
ADSL
UDSL
SDSL
VDSL
VSATTV
SHDSL
STM 1
UMTS
PMP
CDMA
WLAN
Bluetooth
POTSPower line
Tecnologías cableadas de accesoTecnologías cableadas de acceso
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Implantación de las diversas tecnologías
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What is xDSL
DSL: Digital Subscriber Line
DSL as a transmission technology using the existing copper wires between a central exchange and a customer with a bit rate speed up to 26 Mbit/s
Signals: symmetrical/asymmetrical, digital, text, audio, video
Concepts of local loop, management, handshake, interoperability, scalability, legacy
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Why x-DSL
Faster than analog (56 kbit/s) and ISDN (>128 kbit/s) modems, reasonable cost, reach 3-6 km
Less expensive that E1/T1 systems, 1.5-2.0- Mbit/s, reach 1 km
Use already existing copper pairs (depending on the performance): start as equipments installed.Transforms potential 700 millions copper wires installed
worldwide into multimegabit data pipes Scenario convenient to providers and users
immediately available Enable the management of different providers of
different services to different users tipology Alternative: Optical access
Wait for full availability current costbetter performance
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How it works
Remove line components limiting the bandwidth to the voice frequency (4 KHz = 64 Kbit/s)
Use of copper low attenuation frequencies sending more bits x Hertz for longer reach
Use higher bit rate with a low increase of signal rate (baud) in the line
Use of line codes allowing the transmission of 2 to 15 bits x Hertz (up to 1.1, 2.2, 12 MHz)
Adoption of techniques/phylosophies limiting negative effects (crosstalk, echo, spectrum, etc.)
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Bucle de abonado (conexión ADSL)
Redtelefónica
DSLAM (ATU-C)
Router-modemADSL (ATU-R)
Ethernet 10BASE-T
VPI 18, VCI 23, PCR 256/128 Kb/s
VPI 18, VCI 31, PCR 512/256 Kb/s
VPI 18, VCI 37, PCR 2048/300 Kb/s
Circuito permanente ATM
Enlace ATM OC-3 (155 Mb/s)
Red ATM
192.76.100.1/25
192.76.100.7/25
192.76.100.12/25
192.76.100.15/25
Internet
Arquitectura de una red ADSL
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DSLAM Digital subscriber line access multiplexer
A Digital Subscriber Line Access Multiplexer (DSLAM) allows telephone lines to make faster connections to the Internet.
It is a network device, located near the customer's location, that connects multiple customer Digital Subscriber Lines (DSLs) to a high-speed Internet backbone line using multiplexing techniques.
By locating DSLAMs at locations remote to the telephone company central office (CO), telephone companies are now providing DSL service to consumers who previously did not live close enough for the technology to work.
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ADSL G.Lite (ITU G.992.2)
ADSL requiere instalar en casa del usuario un filtro de frecuencias o ‘splitter’ (teléfono de ADSL).
El splitter aumenta el costo de instalación y limita el desarrollo.
ADSL G.Lite suprime el splitter. También se llama ADSL Universal, ADSL ‘splitterless’ o CADSL (Consumer ADSL).
Sin splitter hay más interferencias, sobre todo a altas frecuencias.
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ADSL2 versus ADSL (G.992.3 x G.992.1)
2nd generation of ADSL with improvements on: Loop-reach increase for equivalent bit rates (300m)Higher down/up bit rates loop diagnosticsAdjustable spectrum shaping during operat/initializPower vs traffic control: L0(full),L1, L2 robustness against loop impairments and RFIImproved multivendor interoperability
Improved application support for an all digital mode of operation and voice over ADSL operation;
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ADSL 2+ : G.992.5
PerformanceIncrease downstream: to 16 Mbit/sMaybe increase in upstream (Oct. 2003)Increase reach (1.5 - 3 Km)
ADSL+ doubles the bandwidth (from 1.1 to 2.2 MHz) with a significant increase of data rates on short loops
Backwards compatibility (needs G.992.3)
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VDSL (Very high speed DSL)
Es el ‘super-ADSL’. Permite capacidades muy grandes en distancias muy cortas.
Las distancias y caudales en sentido descendente son:300 m 51,84 – 55,2 Mb/s1000 m 25,92 – 27,6 Mb/s1500 m 12,96 – 13,8 Mb/s
En ascendente se barajan tres alternativas:1,6 – 2,3 Mb/s19,2 Mb/sIgual que en descendente (simétrico)
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Cable Broadband Service
Developed for TV distribution
Evolved to provide TV/Data/Voice
Up to 15 Mbs download; 2 Mbs upload
Distance independent
Register w/ FCC
34 Cable Modem
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Hybrid Fiber/Coax (HFC) CATV Network
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Residential access networks: cable modems
36
Diagram: http://www.cabledatacomnews.com/cmic/diagram.html
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Gigabit Passive Optical Network (GPON) Fiber to the Home Architecture
Central Office
Typically up to 20 km (28 dB)
Passive Outside Plant
2.5 Gbps @ 1490 nm
1.2 Gbps @ 1310 nm
splitters points
Optional 1,550 nm to support local analog/digital video if required
Softswitch(for voice)
Edge router(data, video)
Optical Line Terminal (OLT)
Single family homes
Multi-dwelling units
Small/medium enterprises
Optical Network Terminal (ONT)
Source: Fiber to the Home Council
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Objetivos
Soporte de todos los servicios: voz (TDM, tanto SONET como SDH), Ethernet (10/100 BaseT), ATM,…
Alcance máximo de 20 Km, aunque el estándar se ha preparado para que pueda llegar hasta los 60 km.
Soporte de varios bitrate con el mismo protocolo, incluyendo velocidades simétricas de 622 Mb/s, 1.25 Gb/s, y asimétricas de 2.5 Gb/s en el enlace descendente y 1.25 Gb/s en el ascendente.
El número máximo de usuarios que pueden colgar de una misma fibra es 64 (el sistema está preparado para dar hasta 128).
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Futuro de GPON
GPON no requiere de dispositivos electrónicos u opto-electrónicos activos para la conexión entre el abonado y el operador, y por lo tanto supone una inversión y unos costes de mantenimiento menores
La mayoría de los grandes operadores actuales se han decantado por la tecnología GPON.
En 2007 muchas operadoras han realizado “pruebas piloto” con pocos usuarios. El objetivo de estas pruebas es empezar a vislumbrar las dificultades de trabajar la fibra óptica.
A lo largo de 2008 se espera el lanzamiento “masivo” de servicios sobre GPON.
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Broadband Over Power Lines
40
Power Line Interface Device
Located In Home
High Voltage
Medium Voltage Low Voltage
LV Distribution Transformer
Access BPL
PowerGenerati
onPlant Substation
AggregationPoint
InternetInternet
~ MVolts ~ 1kVolts to 40 kVolts
~ 120/240 Volts
Repeater
Coupler
Backhaul Point (Gatewa
y)
BPL signals are extracted here & converted into/from traditional communication packets for appropriate communication direction
In some Access implementations,these physical links are replaced by wireless links
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Tecnología PLC: Principios básicos
Red de Acceso PLC
Repetidor (Instalado en el Cuarto de Contadores)
HE: Equipo PLC en CT
Terminal (Instalado en Casa de Cliente)
CT2
CT3
CT4
CT5
CT6
CTn
CT1
PuntoInterconexió
n
Conexión a otros
operadores
Terminal
100 – 300 hogares
HE
Repetidor
Media Tensión
(MT)
Baja Tensión
(BT)
CT: Centro de Transformación MT/BT
La Red Eléctrica es un medio hostil para la transmisión de datos: derivaciones, malas conexiones, ruido, impedancia variable...
Modulaciones robustas: DSSS, GMSK, OFDM
No existe ningún estándar, sino un grupo de sistemas diferentes e incompatibles entre sí
Velocidades de transmisión de hasta 200 Mbps compartidos entre los usuarios, y dependiendo de la configuración
Enchufe eléctrico (Toma única de alimentación, voz y datos.)
Permite seguir prestando el suministro eléctrico sin ningún problema
Simetría del ancho de banda
Principios básicos
Una idea sencilla: Acondicionar la red eléctrica para la transmisión simultánea de las señales de baja frecuencia (50/60 Hz) para transmisión de energía y alta frecuencia (1-40 MHz) para transmisión de datos
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El uso de la red eléctrica existente: La principal ventaja de la tecnología PLC y su máximo condicionante
Permite gestión y control en Tiempo Real Bi-direccional Aprovecha la infraestructura eléctrica: Alta disponibilidad (Red de MT mallada) Mejora mantenimiento preventivo (medio
físico compartido) Rapidez de instalación Coste moderado Total independencia de:
• Obra Civil y licencias• Licencias radio• Interferencias• Operadores TELCOM (Internos /
Externos)
Ventajas
Variable en el tiempo Ruido elevado Altas atenuaciones Múltiples reflexiones
Desventajas
Attenuation vs Distance, PLC cables
0
10
20
30
40
50
60
70
80
90
100
110
120
0 50 100 150 200 250 300 350
Distance (meters)
Att
enu
atio
n(d
B)
1.6 MHz
10 MHz
20 MHz
30 MHz
a0 = 2e-3
a1 = 8e-6
k=0.5
A(f,d) = dfaa k
e )( 10
Atenuación vs. Distancia, cables PLC
0
10
20
30
40
50
60
70
80
90
100
110
120
0 50 100 150 200 250 300 350
Distancia (metros)
Ate
nu
aci
ón
(d
B)
a0 = 2e-3a1 = 8e-6k=0.5
A(f,d) = dfaa k
e )( 10
1.6 MHz
10 MHz
20 MHz
30 MHz
Attenuation vs Distance, PLC cables
0
10
20
30
40
50
60
70
80
90
100
110
120
0 50 100 150 200 250 300 350
Distance (meters)
Att
enu
atio
n(d
B)
1.6 MHz
10 MHz
20 MHz
30 MHz
a0 = 2e-3
a1 = 8e-6
k=0.5
A(f,d) = dfaa k
e )( 10
Attenuation vs Distance, PLC cables
0
10
20
30
40
50
60
70
80
90
100
110
120
0 50 100 150 200 250 300 350
Distance (meters)
Att
enu
atio
n(d
B)
1.6 MHz
10 MHz
20 MHz
30 MHz
a0 = 2e-3
a1 = 8e-6
k=0.5
A(f,d) = dfaa k
e )( 10
Atenuación vs. Distancia, cables PLC
0
10
20
30
40
50
60
70
80
90
100
110
120
0 50 100 150 200 250 300 350
Distancia (metros)
Ate
nu
aci
ón
(d
B)
a0 = 2e-3a1 = 8e-6k=0.5
A(f,d) = dfaa k
e )( 10
1.6 MHz
10 MHz
20 MHz
30 MHz
Densidad Espectral de Media Tensión
Tecnología PLC: Principios básicos
TECNOLOGÍAS DE RED AVANZADAS – Master IC 2009-2010 – http://www.grc.upv.es/docencia/tra/
Tecnologías inalámbricas de redTecnologías inalámbricas de red
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Basics of Satellites
Two Stations on Earth want to communicate through radio broadcast but are too far away to use conventional means.
The two stations can use a satellite as a relay station for their communication
One Earth Station sends a transmission to the satellite. This is called a Uplink.
The satellite Transponder converts the signal and sends it down to the second earth station. This is called a Downlink.
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Basics: Advantages of Satellites
The advantages of satellite communication over terrestrial communication are:The coverage area of a satellite greatly exceeds that of
a terrestrial system.Transmission cost of a satellite is independent of the
distance from the center of the coverage area.Satellite to Satellite communication is very precise.Higher Bandwidths are available for use.
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Basics: Disadvantages of Satellites
The disadvantages of satellite communication:Launching satellites into orbit is costly.Satellite bandwidth is gradually becoming used up.There is a larger propagation delay in satellite
communication than in terrestrial communication.
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Basics: How Satellites are used
Service TypesFixed Service Satellites (FSS)
Example: Point to Point CommunicationBroadcast Service Satellites (BSS)
Example: Satellite Television/Radio Also called Direct Broadcast Service (DBS).
Mobile Service Satellites (MSS) Example: Satellite Phones
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Types of Satellites
Satellite OrbitsGEOLEOMEOMolniya OrbitHAPs
Frequency Bands
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Geostationary Earth Orbit (GEO)
These satellites are in orbit 35,863 km above the earth’s surface along the equator.
Objects in Geostationary orbit revolve around the earth at the same speed as the earth rotates. This means GEO satellites remain in the same position relative to the surface of earth.
AdvantagesA GEO satellite’s distance from earth gives it a large coverage
area, almost a fourth of the earth’s surface.GEO satellites have a 24 hour view of a particular area.These factors make it ideal for satellite broadcast and other
multipoint applications. Disadvantages
A GEO satellite’s distance also cause it to have both a comparatively weak signal and a time delay in the signal, which is bad for point to point communication.
GEO satellites, centered above the equator, have difficulty broadcasting signals to near polar regions
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Frequency Bands
Different kinds of satellites use different frequency bands.L–Band: 1 to 2 GHz, used by MSSS-Band: 2 to 4 GHz, used by MSS, NASA, deep space
researchC-Band: 4 to 8 GHz, used by FSSX-Band: 8 to 12.5 GHz, used by FSS and in terrestrial
imaging, ex: military and meteorological satellitesKu-Band: 12.5 to 18 GHz: used by FSS and BSS (DBS)K-Band: 18 to 26.5 GHz: used by FSS and BSSKa-Band: 26.5 to 40 GHz: used by FSS
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Satellite: an example
Ofertas de Telefónica España
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La llegada del 3G
Higher bandwidth enables a range of new applications!!
For the consumerVideo streaming, TV
broadcastVideo calls, video clips –
news, music, sportsEnhanced gaming, chat,
location services…For business
High speed teleworking / VPN access
Sales force automationVideo conferencingReal-time financial
information
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GSM evolution to 3G
GSM9.6kbps (one timeslot)GSM DataAlso called CSD
GSM
General Packet Radio ServicesData rates up to ~ 115 kbpsMax: 8 timeslots used as any one timePacket switched; resources not tied up all the timeContention based. Efficient, but variable delaysGSM / GPRS core network re-used by WCDMA (3G)
GPRS
HSCSD
High Speed Circuit Switched DataDedicate up to 4 timeslots for data connection ~ 50 kbpsGood for real-time applications c.w. GPRSInefficient -> ties up resources, even when nothing sentNot as popular as GPRS (many skipping HSCSD)
EDGE
Enhanced Data Rates for Global EvolutionUses 8PSK modulation3x improvement in data rate on short distancesCan fall back to GMSK for greater distancesCombine with GPRS (EGPRS) ~ 384 kbpsCan also be combined with HSCSD
WCDMA
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Quick Recap of 2G systems: Radio Interfaces
Different in air interfacesModulation and
signaling
eg- GSM 900Uplink: 890-915
MHzDownlink: 935-960
MHz25MHz -> 124 carrier
frequencies, spaced 200kHz apart
One or more frequencies per base station
~270 kbps per carrier, divided into 8 channels = ~33kbps per channel
IS-54BIS-136
GSM
IS-95
IS-95B
WCDMA
AMPSTACSNMT
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2G GSM – Core Network (Voice)
TDMISUP/SS7
PSTNAUCHLR
SCP
SIM
BTS
BSC
Signaling System No. 7 (SS7)
Packet signaling network
Mobile Switching Center (MSC)
Phone switch plus:mobile registration call routinginter MSC handoverslocation updatingCDR creation
SS7 to PSTN
VLR EIR
AuC – Auth. centerEIR – Equip ID registerSCP – Service control point
Home Location Register (HLR)
information of each subscriber, type, service
Current location of the subscriber
Logically 1 HLR per GSM network
Visitor Location Register (VLR)
selected information from the HLR for all mobiles in MSC area
Often bundled with MSC (VLR domain tied in with MSC coverage)
Queries assigned HLR
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BSC
BSC
BSC
Depending on supplier, and design, urban or rural.
About 2-4 BSCs for each MSC
About MSC per 200K subscribers
Many variables
2G GSM – Mobile Switching Center
MSC
Connects to the fixed network (SS7)
Like a normal PSTN/ISDN switch with added mobile functionality:
•Registration
•Authentication
•Location updating
•Handovers
•Integrates VLR
•Call routing to roaming sub…
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GPRS…. What is it?
General Packet Radio Service2.5G data service overlaid on an existing GSM networkMobile station uses up to 8 timeslots (channels) for
GPRS data connection from Mobile StationTimeslots are shared amongst users (and voice)
Variable performance… Packet Random Access, Packet SwitchedSlotted Aloha Reservation / Contention handlingThroughput depends on coding scheme, # timeslots etcFrom ~ 9 kbps min to max. of 171.8 kbps (in theory!)
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GPRS: General Packet Radio Service
TDM
PSTN
AUCHLR
SCP
SIM
BTS
BSC
Packet Control Unit (PCU)
Forward data frames from TDM BSS to packet core
New hardware in BSC
Serving GPRS Support Node(SGSN)
Packet transfer to, from serving area
Registration, authentication, mobility management / handover, CDRs
logical links to BTS, tunnel to GGSN
Gateway GPRS Support Node (GGSN)Gateway to external IP networks (VPN/ISP etc)IP network securityGPRS session mgmt, AAAACDRs for charging
Packet Switched Core
Circuit Switched
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& PCU
IP InternetCorporate
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EDGE… also known as 2.75G
EDGE Enhanced Data Rates for Global EvolutionUses 8-PSK modulation in good conditions Increase throughput by 3x (8-PSK – 3 bits/symbol vs
GMSK 1 bit/symbol)Fall back to GMSK modulation when far from the base
stationCombine with GPRS: EGPRS; up to ~ 473 Kbps. NB:
GPRS & EGPRS can share time slotsNew handsets / terminal equipment; additional
hardware in the BTSCore network and the rest remains the same
TDMA (Time Division Multiple Access) frame structure200kHz carrier bandwidth allows cell plans to remainInitially no QoS; later GSM/EDGE Radio Access Network
(GERAN) QoS addedEDGE access develops to connect to 3G core
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3G Standards groups for UMTS/WCDMA
3G development work has been driven by ETSI, UMTS Forum
WCDMA is the main 3G radio interface (driven initially by DoCoMo)
3GPP = 3G Partnership ProgramProduces specs for 3G system based on ETSI UTRA
(Universal Terrestrial Radio Access Interface)Also develops further enhancements for
GSM/GPRS/EDGESeveral org partners including ETSI, CWTS – China
Wireless Telecommunications Standards www.3gpp.org – eg- Juniper is an active member and
contributor
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Mobile Networks Evolution
GPRS
EDGE
UMTS
HSDPA
2G2G
3G3G
19951995 20152015
4G4G
20052005
DownloadSpeed
1-10 Mbps
250-384 kbps
90-180 kbps
40 kbps
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3G = new network
GSM
HLR
GSM/GPRS Radio network
BSC
2G MSC
Externalvoice
network
GMSC
Packet switched Core network
External IPnetwork
GGSNPCU
2G SGSN
GPRS
UMTS/HSDPARadio network
RNC
UMTS/HSDPA
3G MSC
3G SGSN
Circuit switchedCore network
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…and Beyond
Technology Convergence on OFDM (Orthogonal Frequency Division Multiple Access)
WIMAXStandardized by IEEE 802.16, evolution of 802.11 (Wi-Fi)Improved bandwidth, encryption and coverage over WiFi
Theoretical peak data rates of 70Mbps (practical peak ~2Mbps)Improved QoS better enables applications such as VoIP or
IPTVIdeal application is for “last mile” connectivity to the home
or businessIntel plans to embed WiMAX chips as part of ‘Intel Inside’
L3GTE/HSOPAEarly standardization work starts in 3GPP R8Improved bandwidth, latency over UMTS/HSxPARadio technology based on MIMO-OFDM, peak data rates of
up to 70MbpsNetwork simplification
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Cellular/Fixed: Worlds ConvergeC
overa
ge/M
ob
ility
Data Speeds (Kbps) span a wide range100,00010
802.11n (smart antennas)802.11 with Mesh extns.
802.16e(Mobile)
Loca
l A
rea
Fixe
dW
ide A
rea
Mobile
Metr
o A
rea
Nom
ad
ic
802.16(Fixed LOS)
Cellular Industry
Fixed Wireless Industry
802.16a/d(FixedNLOS)
EV-DO DO+, EV-DV DV+ HSDPA Enhanced UL (R6/R7)
3.5G2G
4G Air Interfaces
Fixed Wireless Industry
2.5G 3G
802.11 b/a/g
Mobile
Broadband
HSDPA
TDD