Tema 1: Redes de acceso a Internet.

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28 Οκτ 2013 (πριν από 3 χρόνια και 7 μήνες)

98 εμφανίσεις

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010


http://www.grc.upv.es/docencia/tra/

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

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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

company

network

regional ISP

router

workstation

server

mobile

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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



4

NBP A

NBP B

NAP

NAP

regional ISP

regional ISP

local

ISP

local

ISP

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

Network Access Points (NAPs)

5

Source: Boardwatch.com

Note: Peers in this context are

commercial backbones.

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

MCI/WorldCom/UUNET Global Backbone

6

Source: Boardwatch.com

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

The situation in Europe

7

See:
http://www.redes.upv.es/ralir/en/MforS/GEANT2.WMV

Also:
http://video.google.com/googleplayer.swf?docId=
-
4949195951027294198&hl=en
-
GB

More about technolgies:
http://video.google.com/googleplayer.swf?docId=
-
4634094763983277329&hl=en
-
GB

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

Hierarchical Routing


aggregate routers into regions, “autonomous systems”
(AS)


routers in same AS run same routing protocol


“intra
-
AS” routing protocol


routers in different AS can run different intra
-
AS routing protocol


Gateway router


Direct link to router in another AS


4
-
8

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

4
-
9

3b

1d

3a

1c

2a

AS3

AS1

AS2

1a

2c

2b

1b

Intra
-
AS

Routing

algorithm

Inter
-
AS

Routing

algorithm

Forwarding

table

3c

Interconnected ASes


forwarding table
configured by both
intra
-

and inter
-
AS
routing algorithm


intra
-
AS sets entries for
internal
dests


inter
-
AS & intra
-
As sets
entries for external
dests


TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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
-
1
0

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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
-
1
1

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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.

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

MPLS as a Foundation for Value Added Services

VPNs

MPLS

Traffic

Engineering

IP+ATM

Network Infrastructure

IP+Optical

GMPLS

Any

Transport

Over MPLS

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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 packets

Label them


At Edge (egress):

Remove Label


(
PE)


Provider Edge


(
P)


Provider


(
CE)


Customer Edge


(
PE)


Provider Edge

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

Control and Forward Plane Separation

LFIB

Routing
Process

MPLS
Process

RIB

LIB

FIB

Route


Updates/

Adjacency

Label Bind

Updates/

Adjacency

IP Traffic

MPLS Traffic

Control Plane

Data Plane

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

MPLS Example: Routing Information

128.89

1

0

1

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 128.89 Thru Me

In

Label

Address

Prefix

128.89

171.69

1

1

Out

I’face

Out

Label

In

Label

Address

Prefix

128.89

171.69

0

1

Out

I’face

Out

Label



In

Label

Address

Prefix

128.89

0

Out

I’face

Out

Label













171.69

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

MPLS Example: Assigning Labels

128.89

1

0

1

0

Label Distribution
Protocol (LDP)

(downstream allocation)

Use Label 4 for 128.89 and

Use Label 5 for 171.69

Use Label 7 for 171.69

In

Label

Address

Prefix

128.89

171.69

1

1

Out

I’face

Out

Label

In

Label

Address

Prefix

128.89

171.69

0

1

Out

I’face

Out

Label

In

Label

Address

Prefix

128.89

0

Out

I’face

Out

Label

-

9

























9

7

4

5

4

5

-

-

171.69

Use Label 9 for 128.89

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

In

Label

Address

Prefix

128.89

171.69

1

1

Out

I’face

Out

Label









4

5

-

-

MPLS Example: Forwarding Packets

Label Switch Forwards
Based on Label

In

Label

Address

Prefix

128.89

171.69

0

1

Out

I’face

Out

Label









9

7

4

5

In

Label

Address

Prefix

128.89

0

Out

I’face

Out

Label

-

9









Data

128.89.25.4

Data

128.89.25.4

Data

128.89

1

0

1

0

128.89.25.4

4

9

MPLS network
egress point

128.89.25.4

Data

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

Un ejemplo: ONO

1
9

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

Un ejemplo: ONO

2
0

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

Un ejemplo: ONO

2
1

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

Coax

Copper

WLL

Satellite

Cellular radio

DECT

AMPS

GSM

PDC

CDMA

GPRS

HSCSD

EDGE

PON

AON

OPAL

BPON

TV analog

Voice

VoD

TV digital

ISDN

4B3T

2B1Q

xDSL

HDSL

ADSL

UDSL

SDSL

VDSL

VSAT

TV

SHDSL

STM 1

UMTS

PMP


CDMA

WLAN

Bluetooth

POTS

Power
line

Tecnologías
cableadas

de
acceso

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

Implantación de las diversas tecnologías

2
3

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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

2
4

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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 cost


better performance

2
5

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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.)

2
6

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

2
7

Bucle de abonado (conexión ADSL)

Red

telefónica

DSLAM (ATU
-
C)

Router
-
modem

ADSL (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

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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.


2
9

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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.

3
0

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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 diagnostics


Adjustable spectrum shaping during operat/initializ


Power vs traffic control: L0(full),L1, L2


robustness against loop impairments and RFI


Improved multivendor interoperability


Improved application support for an all digital mode of
operation and voice over ADSL operation;


3
1

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

ADSL 2+ : G.992.5


Performance


Increase downstream: to 16 Mbit/s


Maybe 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)


3
2

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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/s


1000 m


25,92


27,6 Mb/s


1500 m


12,96


13,8 Mb/s



En ascendente se barajan tres alternativas:


1,6


2,3 Mb/s


19,2 Mb/s


Igual que en descendente (simétrico)


3
3

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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


3
4

Cable Modem

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

Hybrid Fiber/Coax (HFC)

CATV Network


3
5

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

Residential access networks: cable modems

3
6

Diagram: http://www.cabledatacomnews.com/cmic/diagram.html

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

Gigabit Passive Optical Network (GPON) Fiber to
the Home Architecture


3
7

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

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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).

3
8

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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.

3
9

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

Broadband Over Power Lines

4
0

Power Line
Interface
Device Located
In Home

High
Voltage

Medium

Voltage

Low Voltage

LV

Distribution

Transformer

Access BPL

Power

Generatio
n

Plant

Substation

Aggregation

Point

Internet


~ MVolts

~ 1kVolts to 40
kVolts

~ 120/240 Volts

Repeater

Coupler


Backhaul
Point
(Gateway
)

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

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

Tecnología PLC: Principios básicos

4
1

Red de Acceso PLC

Repetidor (Instalado en
el Cuarto de Contadores)

HE: Equipo PLC en CT

Terminal (Instalado en
Casa de Cliente)

CT
2

CT
3

CT
4

CT
5

CT
6

CT
n

CT
1

Punto

Interconexión

Conexión a otros

operadores

Termin
al

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

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

El uso de la red eléctrica existente: La principal ventaja de la tecnología PLC
y su máximo condicionante

4
2


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

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 red


TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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.

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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.

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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.

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

Basics: How Satellites are used


Service Types


Fixed Service Satellites (FSS)


Example: Point to Point Communication


Broadcast Service Satellites (BSS)


Example: Satellite Television/Radio


Also called Direct Broadcast Service (DBS).


Mobile Service Satellites (MSS)


Example: Satellite Phones

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

Types of Satellites


Satellite Orbits


GEO


LEO


MEO


Molniya Orbit


HAPs


Frequency Bands


TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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.


Advantages


A 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



TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

Frequency Bands


Different kinds of satellites use different frequency
bands.


L

Band: 1 to 2 GHz, used by MSS


S
-
Band: 2 to 4 GHz, used by MSS, NASA, deep space research


C
-
Band: 4 to 8 GHz, used by FSS


X
-
Band: 8 to 12.5 GHz, used by FSS and in terrestrial imaging,
ex: military and meteorological satellites


Ku
-
Band: 12.5 to 18 GHz: used by FSS and BSS (DBS)


K
-
Band: 18 to 26.5 GHz: used by FSS and BSS


Ka
-
Band: 26.5 to 40 GHz: used by FSS

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

Satellite
:
an

example


Ofertas
de Telefónica España


5
1

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

La llegada del 3G


Higher bandwidth
enables a range of new
applications!!


For the consumer


Video streaming, TV
broadcast


Video calls, video clips


news, music, sports


Enhanced gaming, chat,
location services…


For business


High speed teleworking /
VPN access


Sales force automation


Video conferencing


Real
-
time financial
information



5
2

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

GSM evolution to 3G

5
3

GSM

9.6kbps (one timeslot)

GSM Data

Also called CSD

GSM

General Packet Radio Services

Data rates up to ~ 115 kbps

Max: 8 timeslots used as any one time

Packet switched; resources not tied up all the time

Contention based. Efficient, but variable delays

GSM / GPRS core network re
-
used by WCDMA (3G)

GPRS

HSCSD

High Speed Circuit Switched Data

Dedicate up to 4 timeslots for data connection ~ 50
kbps

Good for real
-
time applications c.w. GPRS

Inefficient
-
> ties up resources, even when nothing
sent

Not as popular as GPRS (many skipping HSCSD)

EDGE

Enhanced Data Rates for Global
Evolution

Uses 8PSK modulation

3x improvement in data rate on short
distances

Can fall back to GMSK for greater distances

Combine with GPRS (EGPRS) ~ 384 kbps

Can also be combined with HSCSD

WCDMA

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

Quick Recap of 2G systems: Radio Interfaces


Different in air interfaces


Modulation and signaling



eg
-

GSM 900


Uplink:


890
-
915 MHz


Downlink:


935
-
960
MHz


25MHz
-
> 124 carrier
frequencies, spaced 200kHz
apart


One or more frequencies
per base station


~270 kbps per carrier,
divided into 8 channels =
~33kbps per channel


5
4

IS
-
54B

IS
-
136

GSM

IS
-
95

IS
-
95B


WCDMA

AMPS

TACS

NMT


TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

2G GSM


Core Network (Voice)

5
5

TDM

ISUP/SS7

PSTN

AUC

HLR

SCP

SIM

BTS

BSC

Signaling System
No. 7 (SS7)

Packet signaling
network

Mobile Switching
Center


(MSC)

Phone switch plus:

mobile registration

call routing

inter MSC handovers

location updating

CDR creation

SS7 to PSTN

VLR

EIR

AuC


Auth. center

EIR


Equip ID register

SCP


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

Um

Abis

A

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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

5
6

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…


TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

GPRS…. What is it?


General Packet Radio Service


2.5G data service overlaid on an existing GSM network


Mobile station uses up to 8 timeslots (channels) for GPRS data
connection from Mobile Station


Timeslots are shared amongst users (and voice)



Variable performance…


Packet Random Access, Packet Switched


Slotted Aloha Reservation / Contention handling


Throughput depends on coding scheme, # timeslots etc


From ~ 9 kbps min to max. of 171.8 kbps (in theory!)

5
7

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

GPRS: General Packet Radio Service

5
8

TDM

PSTN

AUC

HLR

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 security

GPRS session mgmt, AAAA

CDRs for charging

Packet
Switched
Core

Circuit
Switched

Um

Abis

A


& PCU

IP

Internet

Corporate

FR

Gb

Gn

Gi

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

EDGE… also known as 2.75G


EDGE Enhanced Data Rates for Global Evolution


Uses 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 station


Combine with GPRS: EGPRS; up to ~ 473 Kbps. NB: GPRS &
EGPRS can share time slots


New handsets / terminal equipment; additional
hardware in the BTS


Core network and the rest remains the same


TDMA (Time Division Multiple Access) frame structure


200kHz carrier bandwidth allows cell plans to remain


Initially no
QoS
; later GSM/EDGE Radio Access Network
(GERAN)
QoS

added


EDGE access develops to connect to 3G core

5
9

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

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 Program


Produces specs for 3G system based on ETSI UTRA

(Universal Terrestrial Radio Access Interface)


Also develops further enhancements for GSM/GPRS/EDGE


Several org partners including ETSI, CWTS


China Wireless
Telecommunications Standards


www.3gpp.org



eg
-

Juniper is an active member and
contributor

6
0

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

Mobile Networks Evolution

6
1

GPRS

EDGE

UMTS

HSDPA

1995

2015

2005

Download

Speed













1
-
10 Mbps

250
-
384 kbps

90
-
180 kbps

40 kbps

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

3G = new network

6
2

GSM

HLR

GSM/GPRS

Radio network

BSC


2G MSC

External

voice

network

GMSC

Packet switched


Core network

External IP

network

GGSN

PCU


2G SGSN

GPRS

UMTS/HSDPA

Radio network

RNC

UMTS/

HSDPA


3G MSC


3G SGSN

Circuit switched

Core network

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

…and Beyond


Technology Convergence on OFDM (Orthogonal
Frequency Division Multiple Access)


WIMAX


Standardized 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 IPTV


Ideal application is for “last mile” connectivity to the home or
business


Intel plans to embed WiMAX chips as part of ‘Intel Inside’


L3GTE/HSOPA


Early standardization work starts in 3GPP R8


Improved bandwidth, latency over UMTS/HSxPA


Radio technology based on MIMO
-
OFDM, peak data rates of up
to 70Mbps


Network simplification


6
3

TECNOLOGÍAS DE RED AVANZADAS


Master

IC
2009
-
2010

Cellular/Fixed: Worlds Converge

6
4

Coverage/Mobility

Data Speeds (Kbps) span a wide range

100,000

10

802.11n (smart antennas)

802.11 with Mesh extns.

802.16e

(Mobile)

Local Area

Fixed

Wide Area

Mobile

Metro Area

Nomadic

802.16

(Fixed LOS)

Cellular Industry


Fixed

Wireless

Industry

802.16a/d

(Fixed

NLOS)

EV
-
DO


DO+
, EV
-
DV


DV+


HSDPA


Enhanced UL (R6/R7)

3.5G

2G

4G Air
Interfaces

Fixed Wireless Industry

2.5G

3G

802.11

b/a/g

Mobile

Broadband

HSDPA

TDD