Internet and Wireless Security Laboratory with Dynamic

Kai HwangInternet and Wireless Security Laboratory

University of Southern California

Presentation at ICA3PP2002, Beijing, China, October 23, 2002

Wireless Internet Security with Dynamic Intrusion

Response for M-Commerce

Presentation Outline:

� Wireless Public Key Infrastructure (WPKI) for Securing M-Commerce

� Mobile IPv6 and Wireless TCP for Hybrid 3G Wireless/All-IP Networks

� Risk Assessment for Dynamic IntrusionResponse to Multiple Network Attacks

Core Technology in Wireless Internet

Multi-Mode

Mobile Station

RAN 1(WLAN)

RAN 2(CDMA)

RAN 3(WCDMAor UMTS)

RAN n(other access technology)

Unified All-IP Core Network

IP Backhaul

Intranets

Internet

Mobile Internet Edge :• Mobile Internet Edge Product• WTCP and WTLS Software Suites• Cluster Platform for Wireless Gateway • Storage-area Networking and RAID

Multi-mode Mobile Station:• Mobile IPv6, WTCP• WTLS• 1x EV DO + WLAN• Chipset

MobileInternetEdge

Basic Wireless Security Requirements:

� Confidentiality of exchanges – make sure that nobody can listen in.

� Authentication – Certify the identities of the parties involved.

� Data Integrity - assurance that data is not tampered on its journey.

� Non-repudiation of transactions –assure agreements are legally binding.

Increasing Security Demand inM-Commerce and Pervasive Applications:

� LANs, clusters, Intranets, WANs, Grids, and the Internet all demand security protection hacker-proof operations, crucial to the acceptance of a trust-based digital society

� Innovative mobile wireless services, E-transactions, telemedicine, and digital government; all demand high security, privacy protection, and data integrity.

Public Key Infrastructure Development Trend

Wireless Internet Access andWAP Gateway Functionality Based on WTLS Technology

WTLS: Wireless Transport Layer SecurityThe Protocol to implement wireless security in the

WPKI (Wireless Public Key Infrastructure)

Conceptual Wireless PKI Model

Internet

LCARA LCA server

RootCA RootCA serverRA

HTTP or LDAP

WEB

WEB

Verify cert. from server Verify Certicate.

or Using URL

Cert.Or

URL

(Key distribution) WTLS

Cert.

Cert. for server

DirectoryDirectory

DirectoryDirectory

Trust Propagation by Bridging PKI Domains over Wireline and Wireless Networks

Certificate

CrossCertificate

CrossCertificate

Wireless PKI built with trust lists

CrossCertificate

Bridge CA

WiredCA - 2

Trust List Model

Hierarchical PKI Mesh PKI

Certificate

CA

RootCA

CA

CAWired CA-3

Wired CA-4

WirelessCA-1

Example Trust Path construction from wired CA-3 to wireless CA2:Wired CA-3 �� Wired CA-2, Wired CA-2 �� Bridge CA, Bridge CA�� Wireless CA-1, Wireless CA-1 �� Wireless CA-2

WirelessCA-2

WirelessCA-3

Interoperability of WPKIwith Traditional PKI

SSL/TLS

WTLS

WPKIExpansion

X.509

Mobile ServicesServer

Mobile ServicesServer

RA for Mobile

PKI portal

RA for Mobile

PKI portal

WAP GatewayWAP

GatewayMobil

DevicesMobil

Devices

X.500/LDAP

WTLS SSL/TLS

PKCS #10

Traditional PKI

MobilClient

MobilClient

SmartCardsSmartCards

WPKICA

Server

WPKICA

Server

TraditionalRA

TraditionalRA

DirectoryServer

DirectoryServer

Other CAServers

Other CAServers

OCSPOCSP PKCS #7

PKCS15

Conventional CA

Servers

Conventional CA

Servers

PUBLISH

WTLS CERTIFICATE REQUEST PKCS #10

WTLSCERT.

WTLSCERT.

X.509CERT

X.509CERT

Middleware for Trust Managementon the Bridge CA Cluster

WTLS/X.509Cross

Certificate Engine

WTLS/X.509Cross

Certificate Engine

CRLManagement

Engine

CRLManagement

Engine

Directory/LDAPEngine

Directory/LDAPEngine

Policy Configuration

Engine

Policy Configuration

Engine

Trust Bridging MiddlewareTrust Bridging Middleware

Wireless PKI

Wireless PKI

WirelineX.509 PKIWireline

X.509 PKI

May 20, 2003 Kai Hwang, USC 12

Mobile IPv6, WTCP, and WTLS Protocols for Security in Hybrid

Wireless and IP-Based Networks

Mobile Device

Attachment Points

Wireless Foreign Network

WirelessHome Network

All IP-Based Backbone Network

Fixed Hosts


Home Agents vs. Foreign Agents in Mobile IP Communication

� Each mobile has a Home Agent (HA) and a Foreign Agent(FA). They work jointly to track the network links for tunneling datagrams destined to a mobile device.

� Operation of Mobile IP: The HA and FA make themselves known by advertisement. Agent discovery, registration, and tunneling are 3 major processes

� Tunneling (routing) The HA encapsulates the message from the IP host to the mobile device via its FA. It is desired to achieve optimized routing of the packets destined for a mobile device


Security Features in Proposed IPv6� Support five security Standards published by IETF

� RFC 1825 - Security architecture for the IPv6� RFC 1826 - IP Authentication Header� RFC 1827 - IP Encapsulating Security Payload (ESP)� RFC 1828 – IP Authentication using keyed MD5� RFC 1829 - The ESP DES-CBC Transform

� IP security association and authentication are combined to transmit IP packets

� IPv6 offers options for future expansion in authentication, data integrity, and confidentiality.


Ultimate Goal: Mobile IPv6 � Mobile IPv6 uses the improved IPv6 routing header, along

with the authentication header. Other IPv6 functionalities are optimized to simplify routing to the mobile device

� Mobile IPv6 applies no FA. The mobile device uses an address auto-configuration feature in IPv6 to acquire a care-of-address on a foreign link.

� With the care-of address, a fixed correspondent can send packets directly to a mobile node using the routing headerOtherwise, a correspondent sends the packets, indirectly,thru the home network using source routing


W TLS Stack over W ireless G atew ay

Browser

W TLS

W D P

Phone W ireless G atew ay W eb Server

B earer

W TLS

W DP

Bearer

Server

TLS

TCP

IP

TLS

TCP

IP

Data in the C lear

W irelessN etw ork

Lin kLin k

W iredN etw ork

W ireless Transport Layer Security


WTLS Service Classes (M-Mandatory O-Optional, NA- Not applicable)

Functional Features Class 1 Class 2 Class 3Public-key exchange M M M

Server certificates O M MClient certificates O O M

Shared-secret handshake O O OCompression NA O O

Encryption M M MMAC M M M

Smart card interface NA O O


Wireless TCP (WTCP) for 3G Mobile Wireless Communications

� IST International has implemented 11 WTCP algorithms on Linux servers

� Up-to-6 times of improvement achieved with a subset of the algorithms turned on

Distributed DoS Attacks

Attacker Victim

Z

Z Z

HZ

ZZ ZZ

Z

1. Attacker infiltrates hosts and commands a handler (H). 2. Handler sends commends to zombies (Z). 3. Zombies attack the victim, damaging CPU, Memory and

network resources.


Clustered Security Testbedbuilt at University of Southern California

Internet

Gateway Firewa llPol icy Manager

Nodes with Micro-Firewall

DemilitarizedZone

Router

Router

Nodes with Micro-Firewall

SwitchNetwork

Micro-Firewalls, Benchmark IDS, RADAR Scheme, and Trust Middleware for Developing

Cost-Effective BCA and AAA Servers

Securing Clusters and Intranetswith AAA, Micro-Firewalls, XML,

WPKI, and RADAR Technologies

� Distributed micro firewalls, IDS, and IRS built in the RADAR architecture at USC Labs.

� XML, RMI, CORBA, FTP, HTTP, SMTP, and Aglets evaluated for dynamic security updates

� Provide a full spectrum of VPN, pervasive, and grid-computing security infrastructures using the IPSec, XML, AAA, WPKI, and RADAR technologies


System call interface

User Programs

User Programs

User Programs

User Programs

Micro-firewall

TCP/IP Stack

Network Cards

Memory, file and Process Managers

Disk Drives Main Memory

User Space

Kernel Space

Hardware

Packet Filter

Anomaly Detection

Access Logging

Implementing Micro-Firewall in The Linux Kernel

K. Hwang and M. Gangadharan, “Micro-Firewalls for Dynamic Security with Distributed Intrusion Detection”, IEEE International Symposium of Network Computing and Applications, Cambridge, MA. Oct. 8-12, 2001

RADAR: Risk Assessment for Intrusion Detection with Armed Response

(IDS: intrusion detection system, RAS: risk assessment system, and IRS: intrusion response system)

Responses

IDSIDS RASRAS IRSIRSAttacks

Alarms

Security Policy and Damage/Cost information from Security Administrator

Assessed Risks

Attack characteristics

Intrusions

Set-theoretic Relationships between intrusive attacks and possible responses

f4

Intrusive Attacks

Effective Responses

Detected Attacks true Alarms

Responsive Counter-measuresf1

f3Wasted Responses

False Alarms and Missed Detection

f2

Mappings f1 and f2 are desired, but f 3 and f4 are not wanted

Alarm Matrix from IDS Report

1 to n alarms

1 to n attacks

Detection Misses(False Negatives)

zy

0

xz

False-positivealarms u

= A = (aij)

x : Detection hits y : False negatives z : False Alarms u : False positives

IDS Performance of 5 Attack Programs on USC Linux Cluster

0%

20%

40%

60%

80%

Nimda Code Red Queso Smurf BIND Average

Attack Types

Hit RateMiss RateFalse Alarm Rate

Dynamic Selection ofIntrusion Response Strategies

Start

Is RMax > γγγγ ?

Is EIDS > αααα ?

Is RMax > γγγγ ?Is G > ββββ ?

No

NoNo

No

Yes

Yes

Yes EIDS = IDS EfficiencyG = Alarm Frequency

RMax = Maximum RiskStrategy A

Strategy C

Strategy B

Strategy D

Poor IDS Used

Yes

Improve the IDS

Effects of Threshold in Selecting Intrusion Response Strategies

$150,000/week$50,000/week

30 alarms/week

10 alarms/week

40%

42%

44%

46%

48%

50%

30 alarms/week10 alarms/weekD

C

B

A

γ

β

IRS Efficiency

IRS Efficiency for Different Intrusion Response Strategies

0%

10%

20%

30%

40%

50%

60%

Strategy A Strategy B Strategy C Strategy D

Strategy Type

Ta =10 sec Tm = 1 hourTa =10 sec Tm = 3 hoursTa =10 sec Tm = 6 hours

Conclusions:� Wireless Internet security for M-Commerce

relies on the successful deployment of Mobile IPv6, WTLS, WTCP, and WPKI

� WPKI architecture optimization and itsinteroperability with wireline PKI are the most challenging R/D tasks

� The RADAR scheme offers dynamic security policy update with respect to changes in threat patterns and network conditions

Recent Papers and Presentation:

� K. Hwang, “Wireless PKI and Distributed IDS for Securing Intranets and M-Commerce”, Keynote Address, IEEE Third Int’l Conf. On Parallel and Distributed Computing, Applications, and Technologies (PDCAT2002), Kanazawa, Japan, Sept.4-6, 2002

� K. Hwang and M. Gangadharn, “Micro-Firewalls for for Dynamic Security with Distributed Intrusion Detection”, IEEE Int’l Conf. On Network Computing and Applications, Cambridge, MA. Oct. 8, 2001

�S. Tanachaiwiwat, K. Hwang, and Y. Chen, ” Adaptive Intrusion Response to Multiple Network Attacks with Minimal Risk”, submitted to ACM Transactions on Information and System Security, August 19, 2002, (under reviewing).

Upgrading AAA to Secure Mobile Internet Accesses through Wireless Gateways

• Access equipment include SGSN, GGSN, FA, HA, or PDSN, which can be prototyped on the 3G wireless platform.

• To improves the AAA services with higher reliability, performance, and scalability in billing, auditing, and network planning.

• Must consider the interoperability issues including multi-vendor support, multi-access support, and multiple accounting record supports.

Cluster Middleware, Linux Extensions, and Hardware Support of High-Security

IP Packet Applications

Hardware Support:Hotswap Devices, Router Interfaces

Linux OS Extensions:HA Interface, HA/HW Drivers

I/O Drivers, Platform Management Drivers

Cluster Management MiddlewareFault Management Availability Management

Failback SupportFailover Support Packet Switching

Linux Linux Linux

CPU CPU CPU

Redundant Cluster InterconnectsRedundant Power Redundant Cooling

Design Choices of Bridge CA andWireless PKI Portal at USC

Component Vision Operations Standards

Bridge CACluster

Client Perspective

Certificate Issue, update, renew, and revoke

X.509 V3 certificate,WPKI certificate

Client Certificate handling PKCS #10

Certificate status inquiry/response

OCSP, RFC2560

Other PKIPerspective

Interact with other X.509 PKI CMP, CMC

Directory Certificate Publish LDAP

PKI PortalClient Perspective

Certificate request forwarding PKCS#10

Wireless certificate requests WMLScript

Client Certificate URLs in LDAP LDAP

Other PKI Interact with X.509 PKI CMP, CMC

Residue Risk for 4 Attack Patterns

$0

$200,000

$400,000

$600,000

$800,000

$1,000,000

High Hit ( H75%, M 10%,

S 39%)

High Miss ( H10%, M

75%,S 39%)

HighConfusedAlarm ( H10%, M

50%,S 79%)

RunningExample ( H

48% M 47% S22%)

Hit DamageMiss DamageConfused Alarm Damage

Key Concepts of Mobile IP� A mobile device has a home IP address residing in its home

cellular network. When the device moves to a foreign network, it is given a care-of address

� The IETF (Internet Engineering Task Force) has proposed the Mobile IP as an interface between the home and foreign networks where the mobile device currently resides.

� Mobile IP is a protocol that keeps track the whereabouts and deliver the message to the device at its current location

� A mobile device at home applies the traditional IP in routing packets. When the device moves to a foreign network, the mobile IP is applied using the care-of address.

Internet and Wireless Security Laboratory with Dynamic

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