Um mecanismo baseado em - Unicampluciano/publications/sbrc16-pres.pdf · Um mecanismo baseado em SDN para flexibilizar o controle de tráfego em redes LTE Luciano Jerez Chaves1,2

SBRC’16: The 34th Brazilian Symposium on Computer Networks and Distributed Systems

Um mecanismo baseado em SDN para flexibilizar o controle de tráfego em redes LTE

Luciano Jerez Chaves1,2Islene Calciolari Garcia2

Edmundo R. Mauro Madeira2

1Federal University of Juiz de Fora (UFJF)2University of Campinas (Unicamp)

SBRC’16: The 34th Brazilian Symposium on Computer Networks and Distributed SystemsJune 2, 2016

Outline❖ Introduction

❖ Software-Defined Networking

❖ Long-Term Evolution networks

❖ SDN and LTE integration

❖ Proposed traffic control mechanisms

❖ Literature review

❖ Conclusions and future work

2

June 2, 2016 SBRC’16: The 34th Brazilian Symposium on Computer Networks and Distributed Systems

Introduction

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❖ Mobile data traffic is growing at a compound annual growth rate of 57%

❖ Increasing number of higher-generation connectivity

❖ Multimedia streaming represents more than 50% of mobile data traffic

Exabytes per month

[1] “Cisco visual networking index: Global mobile data traffic forecast update, 2014-2019”, White Paper, Cisco, Feb, 2015.


Future networks

4

❖ 5G networks for people and things

❖ Lower latency and higher data rates

❖ Heterogeneous Networks (HetNets)

❖ High-connectivity backhaul and core networks for more base stations

Software-Defined Networking will be a key differentiator of 5G systems


Contributions

❖ This work contributes with…

❖ OpenFlow protocol integrated into LTE backhaul networks

❖ Specialized OpenFlow EPC controller for LTE traffic control

❖ Network traffic routing

❖ Bearer admission control

❖ Literature review on SDN and LTE integration

5


Software-Defined Networking

6

❖ Decouples the control plane from the data plane

❖ Network intelligence is centralized in software

❖ Simplified distributed forwarding hardware

❖ More agile and cost-effective networks


OpenFlow protocol

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❖ SDN southbound interface

❖ Basic primitives to program the forwarding plane of OpenFlow switches

❖ Concepts of flows to identify network traffic

❖ Switch datapath specification


Long-Term Evolution networks

❖ 4G standard for high-speed wireless communication

❖ Maintained by the 3rd Generation Partnership Project

❖ Evolved Packet System (EPS)

• Evolved Universal Terrestrial Radio Access Network (E-UTRAN)

• Evolved Packet Core (EPC)

8


eNB S-GW P-GWUE Internet

End to End service

Radio bearer S1 bearer

S5/S8 bearerE-RAB bearer

EPS bearer External bearer

LTE-Uu S1-U S5/S8 SGi

E-UTRAN EPC

MME HSS PCRF

S1-MME

S6a

S11 GxGx

Control plane

Data plane

EPS architecture Packet domain onlyStandardized interfacesGPRS Tunneling Protocol (GTP)

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LTE QoS and EPS bearers

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❖ EPS bearers identify packet flows with common QoS treatment❖ Bearers are associated with a QoS Class Identifier (QCI)

❖ Minimum Guaranteed Bit Rate (GBR)

❖ Non-Guaranteed Bit Rate (Non-GBR)


SDN and LTE integration

❖ Proposed integration

❖ OpenFlow switches in the backhaul network (S1 interfaces)

❖ New OpenFlow match fields for GTP TEID routing

❖ No changes in EPC elements for tunnel handling

11


SDN and LTE integration

❖ Proposed integration

❖ OpenFlow switches in the backhaul network (S1 interfaces)

❖ New OpenFlow match fields for GTP TEID routing

❖ No changes in EPC elements for tunnel handling

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Software-Defined Mobile Networking (SDMN)


Network topology❖ Wired backhaul topology

❖ Ring with arbitrary number of OpenFlow switches

❖ Unified S-GW/P-GW gateway element

❖ Ethernet full-duplex links

❖ Wireless access topology

❖ Hexagonal grid with inter-site distance of 500 m❖ UEs scattered closed to the eNBs

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OpenFlowswitch

OpenFlow Ring

Controller

P-GWS-GW

eNB

UE

InternetMME

PCRF


OpenFlow EPC controller

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❖ LTE traffic control mechanisms

❖ Backhaul traffic routing


MME

Cont

rol la

yer

Appl

icatio

n la

yer

OpenFlow EPC Controller- Backhaul traffic routing- Bearer admission control

Internet

Infra

stru

ctur

e la

yer


PCRF P-GW S-GW MME EPC Controller eNB UE

PCC decisionprovision

Confirmation ACK

Create DedicatedBearer Request

RRC connectionreconfiguration

Create DedicatedBearer Response

Create DedicatedBearer Response

Bearer SetupResponse

Bearer SetupRequest


RRC connectionreconfiguration complete

Return

Routing ( )

Admission ( )


OpenFlow EPC controller

Controller communicates with the MME element for bearer management procedures

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Network traffic routing

❖ Look for routing paths and install GTP TEID match rules

❖ For the ring topology, the routing options are reduced to clockwise or counter-clockwise paths

❖ Different routing policies

❖ Shortest Path Only

❖ Shortest Path First

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Bearer admission control

❖ Reserve the requested bandwidth for accepted GBR bearers

❖ Shortest path only routing policy blocks GBR requests when there is no available bandwidth in the shortest routing path

❖ Shortest path first routing policy checks on the other routing path for the required bandwidth before blocking the GBR request

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Performance evaluation❖ Network Simulator 3 + OFSwitch13 module

❖ Backhaul ring size: 4/10 OpenFlow switches connected to eNBs

❖ UE load distributions: balanced or unbalanced (30% of UEs in one half of the ring, 70% on the other half)

❖ Admission control: up to 40% of link bandwidth for GBR traffic

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Traffic applications Traffic type Bearer QCI

VoIP UDP GBR (1)

Live Video Streaming UDP GBR (2)


Block ratio analysis10 OpenFlow switches in the ring

Improved block ratio for the shortest path only routing policy

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0

5

10

15

20

50 100 150 200 250 300 350 400 450

Bloc

k ra

tio (%

)

Number of UEs

Shortest Path OnlyShortest Path First

0

5

10

15

20

50 100 150 200 250 300 350 400 450

Bloc

k ra

tio (%

)

Number of UEs

Shortest Path OnlyShortest Path First

Average block ratio (balanced load) Average block ratio (unbalanced load)


Routing path analysis4 OpenFlow switches in the ring

Improved block ratio for the shortest path only routing policy

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0

20

40

60

80

100

1 2 3 4 1 2 3 4

Rout

ing

dist

ribut

ion

(%)

Shortest Blocked Inverted

Shortest Path FirstShortest Path Only

0

20

40

60

80

100

1 2 3 4 1 2 3 4

Rout

ing

dist

ribut

ion

(%)

Shortest Blocked Inverted

Shortest Path FirstShortest Path Only

Traffic routing distribution (balanced load) Traffic routing distribution (unbalanced load)


Literature contributions for SDMN

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20

Use cases Congestion control

Mobility Management

Mobile backhaul network Venmani et al. 2012

Gurusanthosh et al. 2013



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Use cases

Traffic routing

Congestion control

Mobility Management

Tunnel-based

Tag-based

Flow-based

Mobile backhaul network

Mobile core network

Pentikousis et al. 2013Kempf et al. 2012Hampel et al. 2013

Ali-Ahmad et al. 2013

Venmani et al. 2012


Li et al. 2012Jin et al. 2013



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Use cases

Traffic routing

Traffic managementLoad balancing

Congestion control

Mobility Management

Tunnel-based

Tag-based

Flow-based

Traffic offloading


Mobile core network



Venmani et al. 2012


Nagaraj and Katti 2014

Said et al. 2013Ghazisaeedi et al. 2013




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Use cases

Traffic routing


Congestion control

Mobility Management

Tunnel-based

Tag-based

Flow-based

Traffic offloading

Mobility managementUse cases


Mobile core network



Venmani et al. 2012





Karimzadeh et al. 2014



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Use cases

Traffic routing


Congestion control

Mobility Management

Tunnel-based

Tag-based

Flow-based

Traffic offloading

Mobility management

Traffic control

Use cases


Mobile core network



Venmani et al. 2012





Karimzadeh et al. 2014

Admission controlTraffic routing


Conclusions and future work❖ This paper shows…

❖ How the OpenFlow protocol can be used to assist LTE traffic control management

❖ Backhaul traffic routing


❖ SDMN literature review, focusing on backhaul and core networks

❖ As future work…

❖ Explore traffic control in heterogeneous networks❖ Improve the proposed mechanisms to support UE mobility

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June 2, 2016 SBRC’16: The 34th Brazilian Symposium on Computer Networks and Distributed Systems 22

[email protected]

Documents

Um mecanismo baseado em - Unicampluciano/publications/sbrc16-pres.pdf · Um mecanismo baseado em SDN para flexibilizar o controle de tráfego em redes LTE Luciano Jerez Chaves1,2