Download - MEF 22 Ethernet Based Mobile Backhaul
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MEF 22Ethernet Based Mobile Backhaul
MEF Ambassador to the Americas
Rami Yaron
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• MEF Introduction
• Mobile Backhaul – The Market View
• MEF specifications for Mobile Backhaul
• Multi Physical Transport
• Use Case: Legacy Network Migration
• Phase 2: Preparing for LTE and Beyond
Today’s Webinar Agenda
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MEF 22Mobile Backhaul Implementation
Agreement - Phase I
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MEF 22: Overview
• MEF22 Explains how to apply existing MEF specifications to Mobile Backhaul
• Provides generic specification for Ethernet backhaul
• Includes guidelines to architecture, equipment & operation of the RAN
• Offers a standardized toolset
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MEF 22: Standardization Process
TDM to IP/Eth
Industry trends
Other SDOs
MEFs own work as the foundation
Standardizedreference
points
ServiceRequirements
(Service Types,CoS, Eth OAM, etc)
SynchronizationRecommendations
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MEF Terminology and Concepts
• Network Elements as defined in MEF 22 Specification
Service requirements:• Connectivity - From a few to thousands of sites• Assurance - Capacity, quality and availability• Operations - Provisioning, SLA monitoring, fault-finding
GIWF Generic Inter-working Function
PCP Priority Code Point
PEC Packet based Equipment Clocks
PTP Precision Time Protocol
RAN Radio Access Network
RAN BS RAN Base Station
RAN CE RAN Customer Edge –Mobile network node/site
RAN NC RAN Network Controller –Single or multiple network elements
RNC Radio Network Controller
Terminology used in the specification and this overview
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Legacy RAN Mobile Backhaul Migration
Emulation over Carrier Ethernet – Use Case 1b
Packet offload over Carrier Ethernet – Use Case 1a
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Ethernet RAN Mobile Backhaul Migration
RAN dual stack – Use Case 2a
Full Ethernet – Use Case 2b
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Legacy RAN Mobile Backhaul MigrationUse Case
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Use Case Background
• Mobile Operator operates 2G and 3G mobile networks that utilizes TDM leased lines
• 3G base stations Supports both TDM and Ethernet interfaces• Both systems are FDD (frequency sync)• Mixed configuration sites
Legacy Network
TDM Leased Line (1.5 / 2 Mbps)
3G
2G 2G + 3G2G + 3G
2G + 3G
BSC RNC
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Migration Challenges
– 2G transport– Service definition – Timing delivery– Service monitoring
Problem:• Capacity increase not cost-efficiently sustainable on legacy
network
Solution:• 2G and 3G networks should transport Carrier Ethernet
services
Challenges:
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UNI for TDM-based Base Stations
• Generic Interworking Function (GIWF)– Adaptation and interconnection between legacy mobile equipment
at the BS/NC and the Carrier Ethernet network at the UNI– Enables backhaul of any combination of 2G/3G legacy and
Evolved-3G & 4G voice and data traffic over a single Carrier Ethernet RAN
– Implementation based on TDM circuit emulation standards as well as ATM/HDLC pseudo-wire standards
Carrier Ethernet Network
UNI-NUNI-C
Eth Access Link
EFT
GIWFRAN BS
Non-EthernetI/F
UNI-CUNI-N
Eth Access Link
EFT
GIWF RAN NC
Non-EthernetI/F
Ethernet I/F Ethernet I/F
EVC
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2G(GIWF)
2G + 3G(GIWF)
2G + 3G(GIWF)
3G2G + 3G(GIWF)
Services for Emulated Circuits
EVPL_1
EVPL_2
EVPL_3
EVPL_4
UNI
Carrier EthernetNetwork
BSC
• The GIWF Provides support for legacy circuits over Ethernet• Assumption: Emulation solution requires the following:
– FD = 20ms, FDV = 4ms, FLR=10-5, Availability=99.999%– CIR = 2Mbps, EIR = 0Mbps (per emulated leased line)
• EVCs is defined with the same performance requirements• Bandwidth allocated depends on the number of leased lines
that are emulated, n. CIR = n * 2Mbps
GIWF
RNC
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Services for 3G
EVPL_1
EVPL_2
EVPL_3
EVPL_4
UNI
Carrier EthernetNetwork
• 3G service utilizes the Node B Ethernet interface• Assumptions:
– 3G solution requires 3 CoS
– 3G, BWP for each RAN BS: CIR = 6Mbps, EIR = 4Mbps– Ingress BWP for RAN NC UNI: CIR = 24Mbps, EIR = 12Mbps
• E-LINE/E-LAN may be used as well
EVP-Tree
2G(GIWF)
2G + 3G(GIWF)
2G + 3G(GIWF)
3G
BSC RNC
2G + 3G(GIWF)
GIWF
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CoS Configuration
Service Class Name
Example of Generic Traffic Classes mapping into CoS
4 CoS Model 3 CoS Model 2 CoS Model
Very High (H+) Synchronization - -
High (H) Conversational,Signaling and Control
Conversational and Synchronization,
Signaling and Control
Conversational and Synchronization,Signaling and Control,
Streaming
Medium (M) Streaming Streaming -
Low (L) Interactive and Background
Interactive and Background
Interactive and Background
Very High (H+) High (H) Medium (M) Low (L)
-
FD = 20msFDV=4msFLR=10-5
Availability=99.999%
FD=50msFDV=10msFLR=10-4
Availability=99.99%
FD=100msFDV=10msFLR=10-4
Availability=99.99%
Examples:
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MEF22 Approach to Synchronization
– Packet based methods (in scope Phase 1)• Synchronization quality requirements reference the ITU G.8261 standard• Agnostic to specific methods/implementations like Adaptive Clock
Recovery (ACR), Extended ACR (RTP Header), IEEE1588v2, NTPv4, etc.
– Synchronous Ethernet (in scope phase 2)
– Non Ethernet sync (outside IA scope)
F1+ f2
F1
T1 T2
+/- 50ppb
+/- 50ppb
Time
Mobile cannot lock to BTS2
and call is dropped
BTS2 drifts outside 50ppb window
BTS 2
BTS 1
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Delivering Packet Synchronization
• In-band: Within the mobile data stream– Use packet rate based adaptive clock recovery (ACR) – no additional
bandwidth is needed, must have constant packet rate (MEF8)
– Use CES RTP optional header for synchronization timestamps
• Out of band: Separate from the mobile data stream– For packet based synchronization methods like IEEE1588 and NTPv4
– Map synchronization information to separate EVPL or
– Map synchronization information to a different Class of Service (CoS)
Note: Not all sites use circuit emulation services
UNI
EVPLEVPLCoS Data
CoS Sync
UNI
EVPL_Sync
EVPL DataEVPL Data
UNI
EVPL Data & Sync
EVPL Data & Sync
Sync in separate EVPL Sync uses different Class of ServiceSync within the data EVPL
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OAM in MBH Migration
• Ethernet OAM– Provides Ethernet
management
• Features– Connectivity Fault
Management
– Performance Management
– Link Management
• Deployment– Ethernet starts from Base
Station
– or legacy traffic “converged” onto a Carrier Ethernet Network
2G
T1/E1
T1/E1(TDM + ATM)
Ethernet
3G
LTE
EthernetCarrier
Ethernet
N x GigE
Ethernet
ATM
Ch-OC3 or T1/E1
BSC (2G)
RNC (3G)
NC (4G)
Cell Site MSC
Wireless Provider and Backhaul Operator each have visibility of their own Ethernet performance and fault data
Service ProviderRAN BS UNI RAN NC UNI
Wireless Provider Maintenance Entity
Operator Maintenance Entity
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Preparing Ethernet Services for LTEMEF 22 - Phase 2
ApprovedSpecification
ApprovedDraft
LetterBallot
Working Document
StrawBallots
NewProject
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Current Focus Areas
• LTE– Understand LTE and requirements for Ethernet services
• Synchronization– Frequency synchronization requirements and timing methods
• Resiliency– Discuss how resiliency applies to MBH Ethernet services
• Performance monitoring– What needs to be monitored, establish reference model
• Service performance– Common MBH Ethernet service performance recommendations
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MEF 22 Scope Comparison
ITEM PHASE 1 PHASE 2UNI Service Types Link OAM Service OAM FM Service OAM PM CoS Performance recommendations Packet based sync SyncE Resiliency GSM, WCDMA, CDMA2000, WiMAX 802.16e
LTE
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Summary
• RAN is going IP
• MEF 22 specifies a toolset for defining Carrier Ethernet services
• Carrier Ethernet provides solutions for wireless providers and backhaul operators
• MEF22 Phase 2 underway, preparing Ethernet services for LTE
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Thank YouFor details on Carrier Ethernet for Mobile Backhaul visit: http://www.metroethernetforum.org/mobile-backhaul
[email protected]+1 203 554-1522
Rami Yaron