1
Wireless over Pseudowires
Presented by:Giles HeronDirector of Data Network ConsultingOctober 31st 2006
2 10 November, 2006
Agenda
The challenge of mobile backhaul“Wireless over Pseudowires”Reference designsSynchronisationFuture migration to all-IP
2
3 10 November, 2006
3G Services are Driving Capacity Growth
Goal: Improve Performance Plus Reduce cost of delivery?
Services
Data Rates
Enablers
MobileRAN
Releases
2mbps 14.4mbps 14.4mbps
UMTS HSDPA HSUPA
ATM ATM IPRel 99 Rel 4 Rel 5
?
4 10 November, 2006
Backhaul is The Missing Link
Radio TechnologiesGPRS
EDGE
UMTS
HSDPA
WiFi
WiMAX
DVB-H (Mobile-TV)
ApplicationsApplicationenvironment
GGSN
TDM
EnhancedNetwork Services
PSTN / PLMNMGW
IPbackbone
IMS
IPnetwork
Terminals
BackhaulingRAN infrastructure will have heavy commercial impact20-30% of operator OPEX is spent in backhauling today Many of the mobile broadband enablers are already Ethernet-basedOperator spending moves from radio infrastructure to transport
Applications & CoreGaming
TV
Video on Demand
Imaging
Music
Navigation
Internet
Remote working
?SGSN
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5 10 November, 2006
The Challenge of Future Proof BackhaulApplications
Applicationenvironment
SGSN GGSNCSCF
ISUPSIP
TDM
MGCF
EnhancedNetwork Services
PSTN / PLMN
MGW
IPbackbone
IMS
InternetTDM
BTS BSC
BTS
ATM
NodeB RNC
NodeB
IP
RNC RNC
NodeB NodeB
GPRS
EDGE
HSDPA
HSUPA
WLAN
WiMAX
DVB-H
R99
RNC
BSC
6 10 November, 2006
3G Backhaul Using MPLSCAPEX Savings vs. TDM Backhaul
SDH transport and ATM switching at RNC siteRNC Application (“MPLS” aggregation box directly in front of RNC)
Transport CAPEX Comparison - 4xE1
0,0
1,0
2,0
3,0
4,0
5,0
6,0
100
300
500
700
900
1100
1300
1500
1700
1900
Number of Node Bs
M€
Transport CAPEX Comparison - 8xE1
Number of Node Bs
0,0
2,0
4,0
6,0
8,0
10,0
12,0
100
300
500
700
900
1100
1300
1500
1700
1900
M€
Hub Application (MPLS aggregation boxes distributed to hub sites)
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7 10 November, 2006
3G Backhaul Using MPLSNETEX Savings vs. TDM Backhaul
RNCLong-Lined E1s
RNCPE
Metro Ethernet
Short-Haul E1s
PE
ATM switch
NodeB
8 10 November, 2006
Agenda
The challenge of mobile backhaul“Wireless over Pseudowires”Reference designsSynchronisationFuture migration to all-IP
5
9 10 November, 2006
UMTS Backhaul Using MPLSATM VP Transport
+ Simple to provision- Inefficient transport- Requires CBR QoS for VP
VPI = 1VPI = Y
ATM CellVC Label
Tunnel LabelL2 Header
PW Encapsulation
VPI = 1VPI = X
STM-1ATM
N x E1 IMA
RNCATM PWE
NodeB
10 10 November, 2006
UMTS Backhaul Using MPLSATM VC Transport
+ Frame-based transport for AAL5 VCs+ Enables IP termination at Hub for
management and signalling traffic+ Enables per-VC QoS (CBR, VBR, UBR)- Complex to provision
VPI = 1
VPI = X
VPI = 1
STM-1ATM
N x E1 IMA
RNCATM PWE
NodeB
6
11 10 November, 2006
UMTS Backhaul Using MPLSATM VC cell Transport
ATM CellVC Label
Tunnel LabelL2 Header
ATM CellATM Cell
Cell Cell Cell
PW EncapsulationUsed to Transport
Sync (AAL0)Bearer (AAL2)
Cell Cell Cell
STM-1ATM
N x E1 IMA
RNCATM cell PWE
NodeB
12 10 November, 2006
UMTS Backhaul Using MPLSATM AAL5 SDU Transport
AAL5 SDU
VC LabelTunnel Label
L2 Header
PW Encapsulation
ATMSAR
ATMSAR
Used to TransportSignalling (QSAAL)Other data
Cell Cell Cell Cell Cell CellControl Word
STM-1ATM
N x E1 IMA
RNCATM AAL5 PWE
NodeB
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13 10 November, 2006
UMTS Backhaul Using MPLSIP/ATM Termination into RFC2547
VPN LabelTunnel Label
L2 Header
IP Packet
Used to TransportManagement (Mub)Signalling (SIGTRAN)
Cell Cell Cell
AAL5Term.
VPN Encapsulation
IP PacketMAC Header
N x E1 IMA
ManagementRouter
NodeB
14 10 November, 2006
CDMA 1xRTT Backhaul Using MPLSHDLC Transport
VC LabelTunnel Label
L2 Header
PW Encapsulation
HDLC Frame
chOC3T1
BSCHDLC PWE
HDLC FrameHDLC Frame
BTS
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15 10 November, 2006
GSM Backhaul Using MPLSTDM Transport using SAToP or CESoPSN
Control WordVC Label
Tunnel LabelL2 Header
TDM Data
chSTM-1E1BSCTDM PWE
BTS
PW Encapsulation
16 10 November, 2006
GSM - GPRS Backhaul Using MPLSFR PWs Migrating to IP VPN
Gb interface becoming IPEnables SGSN poolingRequires IP-VPN for GPRS backhaul
FR Payload
VC LabelTunnel Label
L2 Header
PW Encapsulation
Control WordFR PayloadFR Header
FR PayloadFR HeaderVPN Label
Tunnel LabelL2 Header
IP Packet
VPN Encapsulation
IP PacketPPP Header
IP PacketL2 Header
SGSNBSC
FR PWE
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17 10 November, 2006
Agenda
The challenge of mobile backhaul“Wireless over Pseudowires”Reference designsSynchronisationFuture migration to all-IP
18 10 November, 2006
Reference DesignRural Deployment – Optimising Capacity
Capacity Today> Leased T1/E1 or PDH microwave from cell site to hub site> Leased SONET/SDH (or SONET/SDH microwave) from hub to RNC site
Solution: MPLS at Hub Site> Maintain ATM or TDM T1/E1 circuits to hub site> Use MPLS PWE from hub site to RNC site
– Enables clear-channel transport (plus option to use Ethernet if available)– Enables statistical gain between cell-sites
ATM
TDM
RNC
BSC
ATM
TDMMPLS Network
ATM PWE
TDM PWE
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19 10 November, 2006
Reference DesignSuburban Deployment – Adding HSDPA
Capacity Today> Leased T1/E1 or PDH microwave from cell site to hub site> SDH/SONET from hub site to RNC site
Solution: MPLS at Cell Site with DSL offload> Maintain ATM or TDM T1/E1 circuits to hub site> Add wholesale ADSL capacity for 3G data using PWE over IP
ATM
TDM
RNC
BSC
ATM
TDM
MPLS Network
DSLAM
BRAS
PoS/GigE
ADSL2+
DSL Aggregation NetworkIMA
TDM
20 10 November, 2006
PWE over DSL BackhaulUsing MPLS over IP (RFC4023)
Node B
ATM
MPLS Pseudowire
PPPoA
L2TP
PE DSL Modem DSLAM LAC LTS LNS PE RNC
E1 FE ADSL 2+ STM-1
E1
ATM
MPLS
IP
Ethernet
ATM
PPP
VCmux
AAL5
ATM
MPLS
IP
DSL
ATM
PPP
VCmux
AAL5
ATM
MPLS
IP
SDH
ATM
PPP
L2TP
UDP
IP
MPLS
IP
SDH
ATM
PPP
L2TP
UDP
IP
MPLS
IP
Ethernet
ATM
MPLS
IP
Ethernet
ATM
SDH
ATM
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21 10 November, 2006
PWE over DSL BackhaulUsing MPLS over IP (RFC4023)
“Overlay Network” causes control plane challenges> tLDP session as per RFC4447 can be used to provision PWs, but
failure detection will be slow> VCCV-BFD from PE to PE provides faster detection> Need mechanism to notify DSL network failures to the RNC
ATM
TDM
RNC
BSC
ATM
TDMMPLS Network
DSLAM
BRAS
PoS/GigE
ADSL2+
DSL Aggregation NetworkIMA
TDM
22 10 November, 2006
Reference DesignUrban Deployment – Fibre to the Cell Site
Capacity Today> Leased T1/E1 or PDH microwave from cell site to hub location> SDH/SONET from hub location to RNC site
Solution: MPLS at Cell Site> Use FE or GigE over fibre from cell site to hub location> Use GigE or 10GigE over fibre from hub site to RNC site
RNC
BSC
ATM
TDM
MPLS Network
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23 10 November, 2006
Agenda
The challenge of mobile backhaul“Wireless over Pseudowires”Reference designsSynchronisationFuture migration to all-IP
24 10 November, 2006
SynchronisationDistributed
Use external clock at each site> Expensive proposition to provide a clock at every cell-site!
PRCPRC PRC
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25 10 November, 2006
SynchronisationSynchronous Physical Layer
Synchronise all elements from the physical layerDistribute timing from one element to the nextWell known and understood using SDH/SONET or E1/T1 circuitsEthernet Based> G.8261Good fit for rural and suburban scenarios aboveGood fit for urban scenario if deploying a dedicated network
OC-3
GigET1
PRC
26 10 November, 2006
SynchronisationAdaptive Timing
Monitor jitter buffer levelsPerform averaging and low pass filter to detect jitter> Tolerant to packet loss and reordering> Vulnerable to low frequency jitter componentsTwo methods:> Synchronise each pseudowire> Synchronise node using “synchronisation pseudowire”
OC-3
GigE/10GigEFE/GigE
Synchronisation PW
PRC
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27 10 November, 2006
SynchronisationIEEE1588 Precision Time Protocol
Hierarchical tree with master/slave clocksDesigned for testing/automation applications> Being enhanced for telecom applications
OC-3
GigE/10GigEFE/GigE
IEEE1588 PTP messaging
IEEE1588Slave
IEEE1588GrandMaster
PRC
28 10 November, 2006
Agenda
The challenge of mobile backhaul“Wireless over Pseudowires”Reference designsSynchronisationFuture migration to all-IP
15
29 10 November, 2006
3G Backhaul Using MPLSMigration to R5
VPN/VC LabelTunnel Label
L2 Header
IP Packet
VPN or IP-PW Encapsulation
IP PacketPPP Header
IP PacketMAC Header
All-IP TransportVoiceDataSignallingManagement
GigE
N x E1 ML-PPP
RNC
FE
30 10 November, 2006
Summary
The Challenge of mobile backhaul“Wireless over Pseudowires”Reference DesignsSynchronisationFuture migration to all-IP
Any Questions?