ACACIA – Context-aware Edge Computing for Continuous Interactive Applications over Mobile Networks

ACACIA Design

Overview NSF award: #1305384 #1343713

Motivation •  Continuous Interactive (CI) mobile apps

emerging, e.g., AR, VR, and face recognition

•  Many use cases –  Retail, stadiums, tourism, museums etc

•  Characteristics of CI apps

–  Highly responsive –  Compute intensive

Junguk Cho, Karthikeyan Sundaresan, Rajesh Mahindra, Sampath Rangarajan and Jacobus Van der Merwe

Open Question: How should the three entities (user, network, and application) be jointly orchestrated and combined in a service abstraction to deliver low latencies and enable CI application in mobile network?

ACACIA Demo Scenario LTE Connection to Internet ①  Open a CI app (User context) ②  Bind the CI app to ACACIA Device Manager ③  Send user context to MRS from ACACIA Device Manager ④  Create policy rules for the user’s CI app ⑤  Setup a dedicated bearer in network for the user’s CI App through

GW-Cs, MME, eNodeb and LTE modem in mobile device ⑥  Setup flow rules in local S&PGW-U for the dedicated bearer ⑦  Running the CI app with a CI server

MEC RegistrationServer (MRS)

CI Server PCEF

SGW&PGW-C

LTE Modem

Dedicated Bearer (MEC)

Default Bearer (Internet)

MEC

ACACIA Device

Manager

EPC

CI App

UE

Open vSwitch(Local S&PGW-U)

UL TF

Tfo

r MEC

UL TF

T for

In

terne

t

MME PCRF

Open vSwitch(S&PGW-U)

eNodeBs

Ryu SDN ControllerOpenFlow

3GPP Control Plane

3

4

5

6

71

2

0

0.5

1

1.5

2

2.5

0 10 20 30 40 50 60 70 80 90 100

Netw

ork

late

ncy

(se

c)

Background traffic (Mpbs)

Conventional EPC

EPC with MEC

ACACIA

MEC Isolation of CI Traffic Control Overhead RTT Reduction

Always-on for an extra bearer LTE Radio Promotion Event (Release and re-establish) - One event requires 15 control msgs (SCTP (7), GTPv2 (4), OF(4))

Per day Average Worst # of times 929 7200 Data (MB) 2.58 20

0

0.2

0.4

0.6

0.8

1

13 14 15 16 17 18

CD

F

RTT (ms)

QCI 5QCI 6QCI 7QCI 8QCI 9

App Optimization Matching time

0 0.5

1 1.5

2 2.5

1 2 4 8

Matc

hing t

ime (

sec)

The number of clients

ACACIArxPowerNaive

DB size :105 objects Image resolution : 920x720

Current Solutions •  Computation offloading to cloud servers

–  No consideration for mobile network complexities

•  Mobile Edge Computing (MEC) over mobile network

–  Need to modify current mobile network infrastructure and establish new specifications

•  Context discovery & user’s localization –  Significantly help optimize CI application

ACACIA -  Service abstraction framework -  Adapts a holistic end-to-end approach to

enabling low latency CI services over existing mobile networks

-  Leverage client context information through LTE-direct to optimize both network and application processing

ACACIA Design (i)   User context discovery

-  LTE-direct : Pub-sub mechanism -  Publish “service” availability -  Subscribe to “interests”

(ii)   Context-aware traffic redirection -  Request a connectivity between a CI app and closest CI server (on demand)

(iii)   ACACIA Mobile Edge Network -  Use LTE/EPC QoS bearer framework with

SDN and NFV GW-Us (standards-compliant MEC) (iv)  Context-aware application

optimization -  ACACIA device manager provides

location information to the CI server

ACACIA Use Case

LTE RTT (~70 ms)

Retail Shop

AR Server

Computer)Sec,on)

Food)Sec,on)

Salesman

Salesman

“Interest” in laptop

Retail)App)(AR))

“Service” Match

“Service” Non-Match

1"

1"

Customer

2"3"4"

Send: User context info & screen view Recv: Info relevant to the scene ( e.g., price, reviews)

4"

ACACIA Architecture

eNodeB

ACACIAdevice

manager

ACACIAdevice

manager

EPCfunctions

SDN/NFV EPCfunctions

Sub/CIApp

CI Server

Mobile device

Mobile device

Mobile Edge Clouds

Core Mobile Network

User context discovery

Context-aware traffic redirection andNFV-enabled offloading

Context-aware application optimization

LTE-direct communicationNetwork Control

Network Data

Location information

i

ii

iii

iv

Radio Access Network

Pub App

Solutions proposed and studied in standalone manner