NFC-based User Authentication Mechanisms for Personalized IPTV Services

基於近場通訊技術且適用於 IPTV
個人化服務之使用者身分鑑別機制
NFC-based User Authentication Mechanisms
for Personalized IPTV Services
Student : Chun-Kai Wang (王雋凱)
Advisor : Dr. Nai-Wei Lo (羅乃維博士) 2015/06/29

NFC-based User Authentication Mechanisms for Personalized IPTV Services
▪ Introduction
▪ Related Work
▪ Proposed Mechanisms
▪ Security and Performance Analysis
▪ Discussion and Comparison
▪ Conclusion
2
Outline

NFC-based User Authentication Mechanisms for Personalized IPTV Services Introduction
▪ IPTV (Internet Protocol Television)
▪ Combined with modern technologies to deliver high-quality
television content and rich services through IP networks
▪ Features of IPTV
▪ Support for interactive TV
▪ Time shifting
▪ Personalization
▪ Low bandwidth requirements
▪ Accessible on multiple devices
4
Background (1/2)

▪ STB (Set-top Box)
▪ A device at the customer side
▪ Connects an ordinary TV to the external network
▪ Converts the received signal display on the TV screen
5
Background (2/2)

▪ Existing IPTV authentication based on STB-level
▪ STB contains a unique hardware identifier registered by service
provider
▪ STB-level authentication leads to whole family members get the
same access level to IPTV services
▪ Family Services ≠ Personalized Services
▪ IPTV service provider cannot identify who is actually watching a
certain program
▪ Inconsistent with IPTV's main intention to provide personalized
services
6
Motivation

▪ To survey studies on identification for TV viewer
▪ To design a user authentication mechanism for
personalized IPTV services
▪ To develop a proof-of-concept implementation
▪ To analyze security and performance of the proposed
mechanism
▪ To evaluate the system by comparing with existing
solutions
7
Objectives

NFC-based User Authentication Mechanisms for Personalized IPTV Services Related Work
▪ Previous works can be classified into five types:
9
Viewer Identification Systems
Type Object of Identification
Password-based [26] ID, Password
Biometrics-based [8] [27] [38] Face-recognition
RFID-based [34] [39] RFID Tag
USIM-based [36] Subscriber Identification Module
Bluetooth-based [10] Bluetooth Device MAC Address

▪ Short range and wireless technology based on RFID
▪ NFC devices: NFC Reader, NFC Tag, NFC Phone
▪ NFC operation modes:
10
Near Field Communication (NFC)
Operation Mode Initiator Device Target Device
Reader / Writer NFC Phone NFC Tag
Peer-to-Peer NFC Phone NFC Phone
Card Emulation NFC Reader NFC Phone

▪ Conventional card emulation requires Secure Element (SE)
embedded in NFC mobile
▪ HCE allows NFC mobile can emulate a contactless smart card
using only software
11
Host Card Emulation (HCE)
SE-based card emulation HCE-based card emulation

13
Overview (1/2)
The proposed personalized IPTV service architecture
Proposed Mechanisms

NFC-based User Authentication Mechanisms for Personalized IPTV Services Proposed Mechanisms
▪ The proposed mechanisms have two authentication
schemes:
▪ HMAC-based Authentication Scheme
▪ Digital Signature-based Authentication Scheme
▪ Both schemes comprise three phases:
▪ Registration Phase
▪ To register a user becoming an IPTV service subscriber
▪ Authentication Phase
▪ To authenticate a IPTV service subscriber
▪ Key Update Phase
▪ To update the secret key of an IPTV service subscriber
14
Overview (2/2)

Notation Description
The IPTV services provider
The user , who is an IPTV subscriber
The personal computer of the user
The NFC-enabled mobile phone owned by the user
The set-top box , which equipped with NFC reader
The Application Server of
The HCE-enabled mobile app, which is developed by
The email address of the user
The password chosen by the user
The personal information of the user
The cell phone number of the user
The unique identifier of entity
The secret key, only known to entity and
The public key of entity
15
Notations (1/2)

Notation Description
The security (private) key of entity
The X.509 certificate of entity
A random number is generated by entity
The n th nonce value is generated by entity
The n th timestamp is generated by entity
The maximum allowed time interval for transmission delay
Check the message is valid
The message is encrypted by the public key of entity
The message is decrypted by the secret (private) key of entity
The message is signed by the secret (private) key of entity
The message is verified by the public key of entity
A keyed-hash message authentication code of message using security key
Entity send the message to entity
A concatenation operator
16
Notations (2/2)

Registration Phase
17
HMAC-based Auth. Scheme Digital-signature-based Auth. Scheme
Proposed Mechanisms

Authentication Phase
18
Proposed Mechanisms

19
Proposed Mechanisms
pp.21 pp.32

Key Update Phase
20
Proposed Mechanisms

`
Security and Performance
Analysis

NFC-based User Authentication Mechanisms for Personalized IPTV Services Security and Performance Analysis
22
Trust Boundary
Trust boundary and the communication channels

▪ The data received during the registration phase are all correct.
▪ The trusted NFC phone is equipped with secure storage
▪ The NFC channel is insecure
▪ The STB and NFC reader in an open environment, any IPTV
subscriber can use his/her NFC phone to get authenticated
▪ The Internet channel protected by SSL/TLS
▪ The trusted Application Server connects to the database is secure
23
Assumptions

▪ Providing Mutual Authentication
▪ Impersonation Attack resistance
▪ Server Spoofing Attack resistance
▪ Replay Attack resistance
▪ Man-in-the-Middle Attack resistance
24
Security Analysis

▪ 𝐴𝑆𝑆𝑃 gets authenticated by 𝑈𝑖 if it can correctly compute HMAC
value by using secret key 𝐾𝑖,𝑆𝑃
▪ 𝑈𝑖 gets authenticated by 𝐴𝑆𝑆𝑃 if it can correctly compute HMAC
value by using secret key 𝐾𝑖,𝑆𝑃
▪ 𝐴𝑆𝑆𝑃 gets authenticated by 𝑈𝑖 if it can correctly verify the
signature by using public key 𝑃𝐾𝑆𝑃
▪ 𝑈𝑖 gets authenticated by 𝐴𝑆𝑆𝑃 if it can correctly verify the
signature by using public key 𝑃𝐾𝑖
▪ Impersonation & Server Spoofing Attack Resistance
25
Mutual Authentication

▪ Fresh nonce-embedded message
▪ The nonce is a random value that used only once
and not repeated
▪ 𝐴𝑆𝑆𝑃 can detect the message is a replay attack
because the scheme uses nonce, if a nonce is found
inconsistencies, 𝐴𝑆𝑆𝑃 will reject the request
26
Replay Attack

▪ STB-to-AS connection is based on SSL/TLS
▪ MITM attack is practically infeasible on NFC channel
27
Man-in-the-Middle Attack

▪ The prototype system consist of three components:
▪ Application Server (AS)
▪ provides a platform let user register service and apply for key update
▪ Set-top Box (STB)
▪ connected with an NFC reader via USB interface
▪ has an NFC application that can communicate with the HCE-enabled
app installed on the NFC Phone
▪ transfers authenticated messages to the AS for performing
authentication
▪ NFC-enabled Mobile Phone (NFC Phone)
▪ installed an HCE-enabled app that can react to APDU commands
from the NFC reader.
28
Prototype Implementation

▪ Application Server Specifications
29
Experimental Platform (1/3)
Application Server
CPU Intel Core i3-3120M
Memory 4GB DDR3 SO-DIMM
Operating
System
GNU/Linux Ubuntu 14.04.2 LTS
Port TCP/IP

▪ Set-top Box Specifications
▪ ACR122U USB NFC Reader
30
Raspberry Pi Model B+
CPU
700 MHz Low Power ARM1176JZFS
Applications Processor
GPU Dual Core VideoCore IV
Memory 512MB SDRAM
Operating
System
Embedded Linux (Raspbian)
Interface Ethernet, USB, HDMI

▪ NFC-enabled Mobile Phone Specifications
▪ Android OS version 4.4 or above supports HCE
31
Samsung Galaxy Note II
CPU 1.6 GHz Quad-Core Cortex-A9
Memory 2GB RAM
Operating
System
Android 4.4.2 (KitKat)
Connectivity
HSPA+, LTE, NFC, Wi-Fi, DLNA, Wi-Fi Direct,
Bluetooth 4.0

32
Prototype System (1/3)

33

34
NFC Reader
Set-top Box
NFC Phone
TV Screen

35
Demo

36
Performance Test (1/4)
HMAC-based
Authentication Scheme
Key Size
(bits)
Authentication Session Time (ms)
MIN MAX AVG STDEV
HMAC-MD5
Implementation
80 1088 1243 1151.68 37.72
112 1079 1245 1154.31 42.69
128 1099 1277 1157.93 45.16
192 1081 1258 1144.78 35.77
256 1085 1247 1154.76 40.80
HMAC-SHA1
Implementation
80 1115 1280 1169.02 41.95
112 1093 1270 1156.12 39.10
128 1110 1276 1165.03 41.14
192 1105 1279 1161.14 43.03
256 1107 1275 1176.99 44.29

HMAC-based
Key Size
(bits)
MIN MAX AVG STDEV
HMAC-SHA256
Implementation
80 1120 1295 1181.13 34.80
112 1124 1312 1185.57 42.26
128 1138 1323 1206.81 51.74
192 1119 1330 1192.44 46.86
256 1136 1337 1217.65 62.38
HMAC-SHA384
Implementation
80 1173 1365 1247.53 52.04
112 1174 1367 1228.90 49.82
128 1161 1371 1244.92 54.27
192 1171 1360 1229.44 46.65
256 1178 1358 1241.01 51.64
HMAC-SHA512
Implementation
80 1198 1368 1270.54 43.88
112 1201 1382 1274.98 43.24
128 1221 1384 1280.84 43.30
192 1202 1366 1275.36 41.07
256 1219 1386 1279.97 45.44
37

38
Digital Signature-based
Key Size
(bits)
MIN MAX AVG STDEV
DSA-SHA1
Implementation
1024 1372 1509 1443.27 33.50
2048 1478 1632 1561.54 36.47
3072 1954 2120 2038.29 39.28
DSA-SHA256
Implementation
1024 1379 1505 1448.07 29.69
2048 1503 1636 1568.67 33.44
3072 2008 2130 2073.13 29.55
DSA-SHA384
Implementation
1024 1386 1517 1453.33 33.58
2048 1507 1639 1569.62 35.70
3072 2020 2189 2103.23 44.20
DSA-SHA512
Implementation
1024 1389 1530 1453.39 36.39
2048 1524 1641 1576.72 32.52
3072 2032 2178 2107.98 38.38

Digital Signature-based
Key Size
(bits)
MIN MAX AVG STDEV
ECDSA-SHA1
Implementation
160 1228 1371 1289.26 36.21
224 1268 1393 1335.25 26.39
256 1369 1469 1414.48 23.63
ECDSA-SHA256
Implementation
160 1227 1383 1281.03 37.30
224 1278 1387 1331.28 27.57
256 1358 1472 1410.27 22.98
ECDSA-SHA384
Implementation
160 1228 1368 1281.39 37.30
224 1279 1391 1331.86 23.19
256 1366 1463 1405.64 19.31
ECDSA-SHA512
Implementation
160 1229 1395 1285.96 32.29
224 1268 1364 1318.91 19.79
256 1374 1470 1411.78 21.05
39

40
Performance Comparison
Performance comparison of the algorithms used in the proposed schemes

▪ HMAC-based authentication scheme is better than Digital
Signature-based authentication scheme in terms of processing
speed
▪ Selected algorithm is the main factor that effects performance of
the HMAC-based authentication scheme
▪ The key size is the main factor that effects performance of the
Digital Signature-based authentication scheme
▪ Digital Signature-based scheme may be better choice at the
security strength in better than HMAC-based scheme. While the
session time of both scheme is equivalent.
41
Performance Analysis

▪ NFC for User-friendly Operation
▪ Users do not need background knowledge about the technology
▪ Use simply by touching two NFC devices together
▪ Non-password Authentication
▪ Not require to remember password
▪ Resist password guessing attacks
43
Usability
Discussion and Comparison

▪ NFC-enabled STB has been developed
▪ More easily integrate the proposed mechanisms
▪ HCE support could reach 85% of smartphones
▪ New released smartphones are all NFC-ready
▪ Not a barrier for near future
44
Deployability
Smartphone shipments per OS platform Q2 2014

▪ Mobile IPTV Services
▪ Live Stream TV
▪ Customers can enjoy Live TV broadcasting anywhere just with
a smartphone or tablet if they have an Internet connection
▪ Personalized EPG (Electronic Program Guide)
▪ A program guide offers a user friendly environment
▪ STB Remote Control
▪ Easy to control the STB directly from smartphone same as
using the classic RC
45
Service Scalability (1/2)

▪ Agent Tags
▪ Can have a temporary authority that authorized by an
authenticated user, to execute authentication
▪ Typical reader/writer mode of NFC operations
46
Service Scalability (1/2)
Tag ID
Remaining
Count
Remaining
Time
Accepted
Channel
Accepted
Device
00000001 10 - CH-10 TV
00000002 - 24 Hour - Tablet
00000003 30 7 Day - -
00000004 - - CH-2 PC
00000005 5 30 Min CH-5 -

▪ HMAC-based vs. Digital Signature-based
47
Comparison of Two Proposed Schemes
HMAC-based
Digital Signature
Cryptosystem Symmetric Cryptosystem Asymmetric Cryptosystem
Integrity Yes Yes
Authentication
Yes
(not for third-party)
Yes
(support for third-party)
Key Size
(with equivalent security level)
Shorter Longer
Computation Cost Lower Higher
Storage Cost Lower Higher
Additional Infrastructure None
Certificate Authority
(optional)

48
Certificate Authority

Password-based Biometrics-based RFID-based
Identification unit A user A user A user
Authentication factor What you know What you are What you have
Object of identification Username, Password Face-recognition RFID tag
Authentication certifier STB STB
STB, IPTV
Authentication Server
Additional H/W device None Video camera
RFID reader in STB
and RFID tag
49
Comparison with Existing Solutions
USIM-based Bluetooth-based Proposed System
Identification unit A user A user A user
Authentication factor
What you have,
What you know
What you have,
What you know
What you have,
What you know
Object of identification
Subscriber
identification module
Bluetooth device MAC
address
HMAC/Signature
Authentication certifier
3G network,
IPTV Service
Provider
Bluetooth STB
STB, IPTV Application
Server
Additional H/W device 3G mobile equipment
Bluetooth module in
STB and Bluetooth
phone
NFC reader in STB
and NFC phone

▪ NFC-based user authentication mechanisms using HCE
and two authentication schemes are proposed
▪ HMAC-based authentication scheme has lightweight
operations and higher performance
▪ Digital Signature-based authentication scheme is
suitable to design open IPTV services
▪ The proposed mechanisms are suitable for personalized
IPTV services and can be easily deployed onto current
IPTV systems
51
Conclusion
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