Breaking for Commercials:Characterizing Mobile AdvertisingNarseo Vallina-Rodriguez†, Jay Shah†, Alessandro Finamore‡

Yan Grunenberger⋄, Hamed Haddadi§, Dina Papagiannaki⋄

Jon Crowcroft†

University of Cambridge† Politecnico di Torino‡Telefonica Research⋄Queen Mary University of London§

IMC 2012, Boston, MA

2

The web is becoming mobile

* Downloads. As of January, 2012

+25 billion

+10 billion

2

3

The role of mobile ads

73% of Android Apps are free [Leontiadis,HotMobile’12]

Mobile advertising is an important source of income for mobile developers

4

Mobile User

Usage stats

Mediation Services

Mobile Ad EcosystemApp developer

(publisher)

£

5

Traffic Flow: AdMob

DNS Server

media.admob.com googleads.g.doubleclick.netpagead2.googlesyndication.com

IDLE

FACH

DCH

EN

ER

GY

DNS LookupGET: http://media.admob.com/sdk-core-v40.jsGET: http://googleads.g.doubleclick.net/mads/gma?...GET: http://pagead2.googlesyndication.com/pagead/images/…

2 seconds

6 seconds

6

Research Question

How does mobile advertisement delivery impact on the cellular network and the

battery life of the user?

7

Paper contributions

1st characterization and evaluation of mobile ad trafficNO WEB ADS!

Ad traffic is wasteful in terms of energy and spectrum Only network activity for many apps Strong component of users’ daily traffic Static objects, frequently re-downloaded and distributed

over CDNs Do not tuned with the peculiarities of cellular networks

Design of spectrum and energy-efficient ad delivery mechanism

8

Methodology

9

Identifying Ad Traffic

Traces from app execution (tcpdump)

+ Controlled understanding of cause-effect relationships

- Limited to ad networks used by developers

Ad Networks documentation+ Detailed

- Not always available

Inspecting traffic traces from cellular providers+ Identify strategies from different players

+ Large scale impact

- Noisy

10

Rule set

Set of 122 rules identifying: Type of service (ad network, mediation service and

analytics) Type of action (request ad, configuration script, report click,

…) …Domain Object Path Type of

ServiceAction

media.admob.com adk-core-v40.js Ad Network Configuration script

*.g.doubleclick.net mads/gma Ad Network Get Ad

*.googlesyndication.com pagead/ Ad Network Get static content

*.g.doubleclick.net aclk Ad Network Report click

Full rule set: http://www.retitlc.polito.it/finamore/mobileAdRegexDictionary.xlsx

11

+3 million mobile subscribers

Full day traces on a major European carrier

1.7 billion TCP connections (including HTTP headers) 22TB of volume downloaded

Mobile traffic dataset

12

Energy and spectrum overhead

13

Mobile Apps Nature

Mobile apps are usually offline by nature!!!!!

Top AdMob Android Apps

Rank App Name Category Users (%)

1 Angry Birds Arcade 11.48

2 Advanced Task Killer System Tools 9.77

3 Soccer Scores (FotMob) Sports 3.53

4 Drag Racing Arcade 2.69

5 Bubble Blast Arcade 2.69

14

Purity

time

Pure activity period

TCP F

low

s

Definition:

Flow A and flow B are part of the same activity period if:

start(flowA) < start (flowB) < end (flowA)

Mixed activity period

81.1%, 68.2% and 69.7% of activity periods are pure for Android, iPhone and iPad respectively

15

Ad traffic is not tuned with the properties of cellular networks, specially the RNC state machine

Nearly 50% of Adrequests happen within 10 secs.

Session interleave

time

Pure activity period

TCP F

low

s Mixed activity period

interleave

16

Millennial Media

Inappropriate close of TCP connections adds additional energy and spectrum waste

L4 inefficienciesAdMob

§

17

Doubling refresh rate adds 40% of energy overheadInappropriate use of TCP connections adds 10%-40% energy overhead

Energy overheadC

urr

en

t (m

A)

0

100

200

300

AirplaneMode

18

Energy and spectrum-aware ad networks

19

1. Avoiding redundant transmissions

2. Reducing the number of transitions between the power modes in mobile networks

Actually, …

Ad traffic is mainly composed by static content +40% of volume are images Content distributed over CDNs

How to save energy?

20

Exploits well-known techniques Connectivity awareness Flow coordination Batching, caching and pre-fetching

Supports all the features of existing ad networks

Our approach: AdCache

21

Prototype evaluationExisting ad networks

Prototype Evaluation

Up to 50% energy savings!

Cu

rre

nt

(mA

)

0

100

200

300

AirplaneMode

22

Conclusions

23

Summary

Mobile app ads are responsible for energy, traffic and spectrum waste Free applications are mainly offline Lack of caching: users can waste hundreds of

MB/day Ad traffic is not tuned with the RNC state machine Inappropriate use of TCP

Simple traffic management techniques can be beneficial

… more interesting results in the paper!

… and lots of things to do! 3GPP != Ethernet

24

Thank you for your attention!

nv240@cam.ac.uk

POLITECNICODI TORINO

25

Additional Slides

50% of Android devices, 5% of volume

Ad Traffic Volume

26

Strong component of users’ daily traffic

Static objects, heavily re-downloaded The top 10 objects account for 1% of the total volume

27

Players sharing the cake

Google services dominate the ad ecosystem but in Analytic Services

28

Traffic re-downloads

Top 10 objects account for 1% of total volume

29

Google services dominate the ad ecosystem also in terms of flows and volume

Volume and flows

30

Multiple organizations serve ad content Usually, ad nets use services from a single

organization Google and Amazon are the preferred services

Ad content distribution