P2P and DRM Interoperability

References P2P and Content Distribution, ISA 767, Secure Electronic Comm

erce Xinwen Zhang, xzhang6@gmu.edu George Mason University (Some slides of this talk are provided by Dr. Songqing Chen from GMU)

DRM Interoperability in Networked Environments, David P. Maher and A. D. Poonegar, Intertrust Technologies Corporation March 2005

Security and DRM, Joseph Chou, Texas Instruments Unstructured Routing : Gnutella and Freenet, Presented

By Matthew, Nicolai, Paul

Outline P2P Overview P2P systems P2P and DRM DRM Interoperability

P2P Definitions A class of systems and applications that employ distributed reso

urces to perform a function in a decentralized manner. The resources encompass computing power, data (storage and content), network bandwidth, and presence (computers, human, and other resources) - by Milojicic et al.

Any network that does not have fixed clients and servers, but a number of peer nodes that function as both clients and servers to the other nodes on the network - wikipedia

More Definitions the sharing of computer resources and services by dir

ect exchange between systems . - Intel P2P working group

SETI@home: the computers at the edge provide power and those in the middle of the network are there only to coordinate them - David Anderson 2002.

Clay Shirky of O’Reilly and Associate A class of applications that takes advantage of resources available

at the edges of the Internet. Because accessing these decentralized resources means operating in an environment of unstable connectivity and unpredictable IP addresses, P2P nodes must operate outside the DNS system and have significant or total autonomy from central servers

P2P Definitions Sharing Contribution Incentive of sharing and contribution Collaboration As reported in June 2004, P2P traffic makes up 80% t

raffic on the Internet, in which the share of BitTorrent is 53%.

Others are eDonkey, Gnutella, FastTrack, etc.

P2P is not new ARPANET, late 60’s Usenet

Since 1979 UUCP (Unix to Unix copy protocol), NNTP (network news transport protocol) Copies files between computers without central control At the beginning, only UNC and Duke Later, using news server and ISP’s server

DNS Mix of p2p and hierarchical model Early Internet: Hosts.txt includes a set of names and IP addresses and copie

d around the Internet periodically In 1983, DNS was developed for better scalability Hierarchical DNS names

Windows workgroups Network File system

P2P in 21st century Napster music file sharing Powerful home computing resources High Bandwidth networking Negative views on P2P

Illegal copy on copyrighted materials Too much bandwidth consumption of existing

networks Too much uncontrolled/inaccurate/junk contents

P2P Applications andFunctionality Distributed computing

SETI@home (compute-intensive), 1996 SETI: Search for Extraterrestrial Intelligence Using computing power of home PCs to search for radio signals

from extraterrestrial civilizations Data/content sharing

Napster, Gnutella, FreeNet, etc. Communication and collaboration

Instant Messaging (ICQ, AIM), discussion board (Groove), games (Dooms), VOIP (skype)

1st generation of P2P networks Napster Gnutella Super Peer DHT

Napster Example1. When a peer (Bob)

connects to Napster, it informs center server with its IP address and song titles

2. Alice queries for a song, then central server returns bob’s address

3. Alice request the song to bob and download a copy directly

Hybrid P2P Many hybrid application of decentralized and

centralized systems Usenet (backbone or heavy-duty peers) DNS (built in hierarchy) ICQ (direct client-to-client communication with

backup of a server) Napster (decentralized file sharing with centralized

file directory) Dramatically reduced latency Better search engine Not for illegal objects distribution

What is Gnutella? Gnutella is a fully decentralized peer-to-peer protocol f

or locating resources Standard, not a program. There are many implementa

tions of Gnutella (BearShare, LimeWire, Morpheus) Each node in a Gnutella network acts as both a

client and server

What is Gnutella? Peer to Peer, decentralized model for file

sharing Any type of file can be shared Nodes are called “Servents”

What do Servents do? Servents “know” about other Servents Act as interfaces through which users can

issue queries and view search results Communicate with other Servents by sending

“descriptors”

Descriptors Each descriptor consists of a header and a body.

The header includes (among other things) A descriptor ID number A Time-To-Live number

The body includes: Port information IP addresses Query information Etc… depending on the descriptor

Gnutella Descriptors Ping: Used to discover hosts on the network. Pong: Response to a Ping Query: Search the network for data QueryHit: Response to a Query. Provides

information used to download the file Push: Special descriptor used for sharing with

a firewalled servent

Routing 1/2 Node forwards Ping and Query descriptors to

all nodes connected to it Except:

If descriptor’s TTL is decremented to 0 Descriptor has already been received before

Loop detection is done by storing Descriptor ID’s

Pong and QueryHit descriptors retrace the exact path of their respective Ping and Query descriptors

Routing 2/2

A

C

BQuery

Query

QueryHit

Note: Ping works essentially the same way, except that a Pong is sent as the response

D

Joining a Gnutella Network Servent connects to the network using

TCP/IP connection to another servent. Could connect to a friend or

acquaintance, or from a “Host-Cache”. Send a Ping descriptor to the network Hopefully, a number of Pongs are

received

Querying Servent sends Query descriptor to nodes it is

connected to. Queried Servents check to see if they have

the file. If query match is found, a QueryHit is sent back to

querying node

Downloading a File File data is never transferred over the Gnutella

network. Data transferred by direct connection Once a servent receives a QueryHit descriptor, it

may initiate the direct download of one of the files described by the descriptor’s Result Set.

The file download protocol is HTTP. Example:GET /get/<File Index>/<File Name>/ HTTP/1.0\r\nConnection: Keep-Alive\r\nRange: bytes=0-\r\nUser-Agent: Gnutella\r\n3

Direct File Download

A

C

BQuery

Query

QueryHitTCP/IP

Connection

Problems with Flood Query Scales poorly: Querying and Pinging generate a lot of

unnecessary traffic Example:

If TTL = 10 and each site contacts six other sites Up to 10^6 (approximately 1 million) messages could be generated. On a slow day, a GnutellaNet would have to move 2.4 gigabytes per second

in order to support numbers of users comparable to Napster. On a heavy day, 8 gigabytes per second (Ritter article)

Heavy messaging can result in poor performance

Problems with Flood Query Traditional Gnutella flood query

has a number of problems Very large number of packets generated to fulfill

queries Most searches on Gnutella can be satisfied with a

search that visits fewer nodes Essentially, just a Breadth First Search (BFS) Some proposals attempt to address this with

alternate schemes for searching

Alternatives to Flood Query Iterative Deepening Directed BFS Local Indices Random Walkers

Issues Several alternatives (Local Indices, Iterative Deepenin

g) require a global policy to be understood by all nodes

Sharing information about file index (Local Indices) or even statistics (Directed BFS) leads to possible security risks

Most, require at least some modification to the servents

Overall Simple Protocol Not a lot of overhead for routing Robustness?

No central point of failure However: A file is only available as long as the file-

provider is online.

Vulnerable to denial-of-service attacks

P2P and DRM

P2P P2P networks are good for distribution of

unprotected files. Uniformed copies obtained by different peers Difficult to define rights More difficult to enforce

>90% of files in P2P are unauthorized. Leveraging P2P for legal content distribution is

a new problem.

Current Situations P2P networks are popular.

Mainly for unauthorized copies of IP Fighting between content

owners/manufactures/providers and P2P users/developers

Recent Supreme Court has ruled that developers can be held responsible for the copyright infringement that their P2P file sharing products allow.

DRM Basic requirements of DRM:

Package, publish, and protect object content Expression of digital rights Authentication of user/devices and

Authorization to access/use the content Enforcement mechanisms

Client side Payment integration

DRM Common Architecture

P2P vs. DRM To IP owner:

P2P offers open invitations to copyright infringement and IP theft.

DRM is the way to protect their revenue on Internet.

To end users/consumers: P2P is the open functionality of the Internet,

and provides freedom of information era. DRM restricts user behaviors.

P2P vs. DRM As a technical issue, P2P supports many new

business models with DRM P2P streaming Paid access with controlled sharing

iTunes

P2P and DRM Integration of DRM into P2P network

Embracing the functionality of P2P Maintaining control over IP

Multiple vendors in value chain: P2P publisher, IP owner, license agent,

payment agent, etc.

DRM Technology Features forP2P Networks (Rosenblatt) Reasonable usage support for users:

Use on any devices Space shifting

Interoperability of identity schemes for both users and devices

Format conversions or transcoding

DRM Technology Features forP2P Networks (Rosenblatt) Lightweight superdistribution

User-defined business models and easy to implement

DRM Technology Features forP2P Networks (Rosenblatt) Standards Support

Rights Expression Languages Define rights for peers

Network Identification Universal or interoperable identity schemes for users

and devices Windows Live ID (formerly .NET Passport) Liberty Alliance (Federated id)

Web Services Services for DRM schemes

authentication, payment, license, etc. Minimize cost and complexity for peers in P2P

DRM Technology Features forP2P Networks (Rosenblatt) User Experience:

Installation of the DRM has to be seamless Use cross-platform technologies (Java, XML, etc)

Payment process should be integrated with ISP and other service providers.

E.g., cell phone SP Content usage track should respect user

privacy.

Gaps in Existing DRM Cost-related functionality limitations Device Tethering

A content object only can be supported on a specific device.

Lack of superdistribution support Complexity of integration

P2P Architecture for DRM Hybrid P2P

Decentralized content distribution Centralized management:

License, authentication, payment, etc.

DigitalContainersHybrid P2PFile Trading

• All transactions tracked• No bottlenecks• DRM• E-commerce• Great use of resources

From Secure File Delivery System for Consumer and Enterprise Peer-to-Peer Networks, DigitalContainer Inc.

What are Digital Containers?

DigitalContainers “wrap” files in a secure multimedia digital shell that can only be opened with a “key”.

Simple as a password Unique as an individual’s fingerprint (Biometric) Created and delivered in a patented process in which the container “talks” to r

emote authorization authorities Any combination of the above: Multi-Factor Authentication

The containers are tracked perpetually as their content is passed securely from person to person, with only authorized individuals being able to access the protected content.

Who, Why, Where, When, How Much? Credit/Debit/Phone card payments

Basic Container Structure

Basic P2P Business Model

Basic P2P Business Model

Packager widely available and easy to use Content owners package digital goods in Digital

Container They register content, set price, and agree to payment

terms P2P network provider gets percentage Content owner gets percentage People get paid all along the value chain

Sample P2P Integration Scheme

External Control-based DRM Separated distribution of content and

meta information Control set (or rules, policies) are

distributed separated from content Service-oriented architecture for

authentication, control, payment, etc

DRM and P2P Pure P2P networks:

trust management in P2P Web of trust Datta et al, “Beyond “web of trust”: Enabling P2p E-com

merce”, IEEE International Conf. on E-Commerce,2003. Reputation management in P2P

eBay

DRM Interoperability

Overview What is the DRM interoperability problem?

DRM systems work as closed domains Unsatisfactory consumer experience

Why should we care? Consumers will subscribe to illicit services, seeking a

better experience Approaches to a Solution

Coral’s approach: standardize interoperability NEMO technology Summary

Security and DRM DRM is Based on Security Principals

Authentication (device, user, service) Key management, data encryption and

signature for data confidentiality and integrity

Secured delivery of premium content usage rights

Can be used for personal content protection DRM Interoperability is Needed PERM Interoperability Framework

Issues with DRM System Diversity

Lack of a unified and open DRM system standard for PC, CE and mobile handheld devices for content interoperability

Current DRM system implementations are not interoperable

Diversity of smart card implementations Diversity of internet DRM system implementations Diversity of packaged media content protection

implementations Mismatches between different trust and protection

models Mismatches between rights expression languages Consumer devices cannot locate and connect to all

needed services/content

DRM Interoperability Problem

DRM systems operate as closed domains or “silos”

Content is not portable outside silo – by design Consumer confusion and dismay

Consumers’ media needs are changing Home networks include CE, mobile, and PC-based

devices Different possible media gateways: Cable box, PC,

Mobile device Expect seamless play of acquired content on all

their devices Ripping and P2P networks offer content

portability and ease of use

Limited Consumer Experience

Consumers expect to use content on any oftheir devices. They are dissatisfied when their content is not portable because of DRM.

Why DRM interoperability? Intuitive Anytime, anywhere consumer

experience with licensed content Reduces dependency on a single

technology silo Anticipates further convergence between

CE, mobile, and PC platforms Future-proof business models Illegal P2P content distribution networks

already offer it

Possible Customer Experience

Technology exists to allow consumers to usetheir DRM-protected content seamlessly,whenever and wherever they want.

Alternate Approaches Allow a de facto standard to evolve

Value chain participants can be at the mercy of a single technology provider

Standardize a universal end-to-end DRM system Unfeasible to address requirements of entire

value chain from CE, mobile, and PC markets in a single system

Standardize a DRM-neutral interoperability architecture

Diversity of Security, ContentProtection/DRM Implementations

Pre-recorded/Recordable content (DVD, DVD-Audio) CSS (Prerecorded DVD) CPPM (Prerecorded Audio) CPRM (Recordable Audio/Video)

Internet streaming audio/video content Various DRMs

WM DRM 10, Fairplay, Real, Open Magic Gate, OMA, SDMI and etc. Broadcast content

Smart Card DRMs DigiCipher, Cable Card ITU-T SG9, DVB-CSA, DirectTV, Multi-2, NDS (ICAM), Irdeto, Nagr

a, DVB Content Protection and Copy Management (CPCM) and many others. Between media client and TV/display

HDCP (HDMI/DVI) DTCP/1394/USB (1394/USB) Macrovision (analog TV)

Rationales of DRM InteroperabilityFramework

Users are able to locate and connect to the content services that they need

A security protocol can be used to protect personal contents or clear contents from the original content owners

An open DRM interoperability standard accelerates content consumption in the home network and propels device volume growth and thus benefits the consumers, the content owners and the device manufacturers

DRM Interoperability

Coral Approach Unite consumer media value chain participants

Include content owners, device makers, technology and service providers

Create open standards for interoperability between consumer DRMs

Avoid changes in current DRM systems Define roles, services, interfaces, and tools to bridge betwe

en incompatible systems Develop a compliance infrastructure

Develop program to certify that solutions comply with architecture and ecosystem specifications

Content providers publish to Coral usage models Ecosystem matches usage model to a device DRM

Decomposition of DRM Components and Services

Content packaging Licenses, Rules and their management Identity management for individuals, groups, other

entities Policy management for services Offer management Fraud management Key and token management Security components and methods

Secure packaging Secure transport, storage Secure execution and process isolation

Different components and services can be offered by different expert providers

Decomposition into functional Tiers

Asset Management and Content Origination

Bundling and Distribution Services

Home and Enterprise Gateways

Devices and Personal Networks

Coral Architecture Specification

Consists of three layers Roles

Describe functionality and behavior Act as a hook for compliance

Interfaces between roles Provide interoperable messaging

Nodes Group roles together in a secure deployment container

Nodes and roles are certified for secure, trusted, policy-managed communications across implementations

Works online and offline Application of NEMO, Intertrust’s reference technolog

y for DRM interoperability

NEMO Technology Stands for: Networked Environment for

Media Orchestration Service-oriented architecture Framework for building distributed

applications that include: Security Trust management Policy management

How Coral uses NEMO Uses NEMO framework to define services

such as: Rights mediation: maps usage models

between DRM systems Principal identity provider: maps usage

identities between DRM systems Rights registry: used to implement rights

locker-type services These and other services form the

foundation of an interoperability layer

How NEMO works

Possible Scenarios Online Scenario

both content and licenses are acquired online

Offline Scenario content and licenses are transformed locally

Hybrid Scenario licenses are acquired from an online service content is transformed locally

Online Scenario

Offline Scenario

Hybrid Scenario