Vancouver, BC July 27-30, 2015
Birds of a Feather
Carrier Ethernet Servicesover LTE
Rami Yaron, Telco SystemsGlenn Parsons, Ericsson
2
Agenda
• Motivation/Background• LTE• Potential solution
Motivation
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85% mobile by the end of 2020
5
Motivation
• More and more traffic is now terminated on mobile devices• Customers would like the same SLA weather they are at the
office, home, or traveling • Fiber availability is limited • Copper plants are old and deteriorating• Optimized for low bandwidth (T1 replacement) • Low CAPEX (FedEx vs. Technician)• Service on demand (time to deliver = Revenue)• Fast activation • High availability services • IoT• OOB management for SDN networks
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Use Case # 1
Primary Connectivity
Using LTE for primary connectivity in rural area that have no other transport method
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Use Case # 2
Backup Connectivity
Using LTE as backup connectivity for high availability traffic
8
Use Case # 3
Temporary Connectivity
Using LTE for immediate connectivity till primary connectivity is ready
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Use Case # 4
Internet of Things
Machine to machine low bandwidth communication
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Use Case # 5
Backdoor for Management
Using LTE for OOB management traffic
LTE
12
LTE
• LTE supports ~100M
• LTE-A Supports up to ~300M
• LTE could support SLA/policy per user/group
• Multi CoS could be supported over LTE (requires CoS mapping)
• CIR could be supported (requires dedicated Bearers)
• 3GPP release 10 support IP fragmentation
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LTE Advanced
Enhanced ICIC
Coordinated Multi Point
+++
Carrier Aggregation Multi-antenna
extension
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• Single Data Radio Bearer Service– Carries user traffic between EPS and the user terminal– Non-Guaranteed bit rate – Multiple data flows can be multiplexed onto single data radio bearer
Internet EPS
EPCLTE
Peer EntitySAE GWUE eNB
End – to – end service
EPS Bearer Service External BS
LTE Radio Bearer Service LTE Access Bearer Service
Physical Radio Bearer Service Transport Bearer Service
LTE Single Radio Bearer per User
Carrier Ethernetover LTE
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Wireless Access Solution: LTE/EPC
• Standard EPC (with a small addition)...– Dedicated bearer per access seeker – with CoS mapping
• CPG (SGW/PGW/WGW) deployed at Exchange points– Encapsulating Ethernet Frames in IP for transport over the
LTE/EPC Network– Mapping Layer2 QoS to Layer3 QoS
MINI-LINK SGW / PGw
eNB Encap
SAPC
Access Seeker
WGW
MME
CPG
WirelessModem
WNTD
UNIClient
LTE
HSS
SP310
EVC/OVC
UNIClient
Access Seeker
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Core Related Features
• Ethernet over LTE (Soft-GRE)• C-VLAN and S-VLAN Tagging• Multiple Bearers, via DSCP TFT QCI Selection• Combined CPG
– Core Site Router and Edge-Switch Design
• MME Pool • No Mobility or Charging
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WNTD features
• WNTD – Wireless NTU Terminal Device– Specification to match Core features
• Subscribers fixed/locked to a cell – using eNB PCI (Cell ID)
• Provisioning Server for WNTD• Also supports
– SOAM – (802.1ag and Y.1731)– Ping Monitor: multi-level periodic ping: the CPG,
Soft-GRE end-point, MME, etc.
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MTU: No Fragmentation E2E
C-TAG FCS
FCS
Ethernet Payload
Ethernet Payload
TAG FCS Ethernet IP UCP GTP IP GRE MPL5 Ethernet Payload
IP GRE MPL5 Ethernet Payload
TAG FCS Ethernet IP GRE MPL5 Ethernet Payload
C-TAG FCS Ethernet PayloadS-TAG
Ethernet
4 bytes 4 bytes
4 bytes 14 bytes
1500bytes
4 bytes 4 bytes 14 bytes
20 bytes
8 bytes 8 bytes 20 bytes
4 bytes 4 bytes 14 bytes
1500bytes
4 bytes 4 bytes 14 bytes
1500bytes
4 bytes 4 bytes 14 bytes
20 bytes
20 bytes
4 bytes 4 bytes 14 bytes
1500bytes
4 bytes 4 bytes 4 bytes 14 bytes
14 bytes
DST MAC = 6 bytes +SRC MAC = 6 bytes +EtherType = 2 bytes
802.3 Ethernet Frame ContentsEthernet header
SRC = Loopback MACDST = IAC context dot1q
Interface
Ethernet headerSRC = SGW S1U
DST = enodeB s1U l/f
WirelessNTU
eNodeB
Air InterfaceEncapsulation
Loopback
Backhaul
OR CPG
1500bytes
MEFUNI
MEFUNI or ENNI
Encap
SGW / PGw
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Challenges
• SLA over wireless is difficult to guarantee– Air interference
• Picking an Ethernet over IP tunnel protocol– Any specification would be of the tunnel
protocol (inside the EVC) and its configuration• Mapping to a dedicated bearer
– Including maintaining CoS marking and treatment (inside the EVC)
• Maintaining GRE tunnel during core failure events
end of session
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