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Integrating security in a quality aware multimedia delivery platform

Paul Koster

21 november 2001

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Contents

Introduction Research question Technology overview Design Demonstrator Evaluation Conclusions & recommendations Questions

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Internet

Introduction

Trends in multimedia delivery Increase in available multimedia

content on the Internet: multimedia streaming

Commercial multimedia services Quality cannot be guaranteed

on the Internet: best-effort service

Increasing interest in security▬► Quality of Service

??

Context QuAM (Quality Aware Middleware)

Assignment Integrate security

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Research question

How can security be integrated in a quality aware multimedia delivery platform that supports performance guarantees?

What types of security?

How to extend QuAM?

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Technology overview (1/4)- Quality of service

best-effort quality cannot be

guaranteed for overloaded network

performance QoS bandwidth

reservation guarantees quality

security QoS

QoS is the run-time non-functional characteristics of a distributed system

QoS mechanisms realize performance and security aspects

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Technology overview (2/4) - Performance

Performance QoS aspects: Bandwidth

Latency

Jitter QoS mechanism: RSVP

Admission control

Claim of resources

reservation

no reservation

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Technology overview (3/4) - Security

Security types Confidentiality Integrity Authenticity Authorization Visibility (anonimity) Availability

Secure network protocol needed Proprietary protocols IPsec

• Currently mainly used for VPNs (static configuration)• But we need dynamic created secure links, because

# Changing relationships# Control of resources

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Technology overview (4/4) - Security & performance interactions

Security and performance conflict: RSVP cannot reserve bandwidth for IPsec flows

Encryption costs computing capacity

However, solutions exist: RSVP support for IPsec data flows

Resource management

IPsec + reservation

no reservation

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Design (1/2) - Layers

QoS support for multimedia delivery

MM Applications

Middleware

Network & hosts

ObjectObject

RSVPIPsec

QuAM

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Client

Design (2/2) - QuAM Architecture

MediaConsumer Media

Producer

Server

Coordinator

IPsec RSVPRSVP IPsec + RSVP support for

IPsec data flows

Resource agent

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Demonstrator

The demonstrator is an example application created on top of the implementation.

The middleware is able to setup a secure path with resource reservations.

The user can select his quality of service without being aware of the underlying technologies.

Routers have been extended to support the combination of IPsec and RSVP.

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Evaluation (1/3)

Requirements Confidentiality and integrity protection with authentication have to

be supported for the multimedia data on the network. Performance (bandwidth) guarantees have to be supported. Performance enforcement may not be affected by security.

Evaluation Performance

• Network# RSVP

• Server CPU load # Admission function

Security analysis• CC (Common Criteria for Information Technology Security

Evaluation)

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CPU load caused by a different number of jobs

0

20

40

60

80

100

120

0 50 100 150 200 250 300 350 400 450

Inserted number of jobs (128kbps)

CP

U l

oad

(%

) (C

use

d, j

ob

-typ

e)

Sender (AH)AH

Evaluation (2/3) - Performance

First step to model CPU usage CPU load is propertional to bandwidth requirements

Different encryption algorithms have different requirements Admission function

• ∑ bwtype·ctype ≤ Cap

Maximum number of jobs per job type

0,00

2,00

4,00

6,00

8,00

10,00

12,00

14,00

16,00

18,00

20,00

0 50 100 150 200 250 300 350 400 450

Inserted number of jobs (128kbps)

Me

as

ure

d n

etw

ork

ba

nd

wid

th

(Mb

ps

)

AH (SHA1)

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Evaluation (3/3) - Security

ClientRouter

QuAM server running e.g.: middleware / webserver

MM Server

12345

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1 MM data (e.g. RTP protocol)2 MM control (e.g. RTSP)3 MM delivery quality feedback (e.g. RTCP)4 Resource reservation protocol (e.g. RSVP)5 Middleware communication (e.g. CORBA)

CC: Protection Profile TOE (Target of Evaluation)

Assumptions

Threats

Objectives

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Conclusions

Some security types can be succesfully offered to applications.

Low-level mechanisms are required to enforce QoS. These may interact however. The design and implementation take this into account.

Achievements Implementation of RFC 2247 (RSVP support for IPsec data flows)

Reported and fixed various bugs for the RSVP daemon and the FreeBSD IPsec implementation.

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Recommendations

Use of open standards and protocols Security analysis: towards overall security Support for authentication, authorization and billing Resource modelling

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Questions