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Action Items for this session• Learn something!• Take notes! • Fill out that evaluation. I love to see your comments and
we want to make these better!• Most important: Have fun today!
Why should you care about wireless security?B ecause “31337 h4x0r” like this: … are equipping vehicles like this: … and using tools like these:… to get info about your W LA N :… so they crack it and gain access:… so they can “ØwN jØ Ø ” like this:
Agenda• Overview of Wireless Solutions• Securing a Wireless Network• Implementing a WLAN Using Password
Authentication• Configuring Wireless Network
Infrastructure Components• Configuring Wireless Network Clients
When designing security for a wireless network consider:• Network authentication and authorization• Data protection• Wireless access point configuration• Security management
Identifying the Need to Secure a Wireless Network
Security Threats Include:• 1.Disclosure of confidential information • 2.Unauthorized access to data• 3.Impersonation of an authorized client• 4.Interruption of the wireless service • 5.Unauthorized access to the Internet• 6.Accidental threats• 7.Unsecured home wireless setups• 8.Unauthorized WLAN implementations
Common Threats to Wireless Networks
Understanding the Standards and Technologies
Standard Description
802.11 A base specification that defines the transmission concepts for Wireless LANs
802.11a Transmission speeds up to 54 megabits (Mbps) per second
802.11b11 MbpsGood range
802.11g
802.11i (WPA2)
54 Mbps Shorter ranges than 802.11bEstablishes a standard authentication and encryption process for wireless networks
802.1X - a standard that defines a port-based access control mechanism of authenticating access to a network and, as an option, for managing keys used to protect traffic
Wireless network implementation options include:• Wi-Fi Protected Access with Pre-Shared Keys
(WPA-PSK)• Wireless network security using Protected
Extensible Authentication Protocol (PEAP) and passwords
• Wireless network security using Certificate Services
Implementation Options
Choose the right solution
Wireless Network Solution
TypicalEnvironment
Additional Infrastructure Components
Required?
Certificates Used for Client
Authentication
Passwords Usedfor Client
Authentication
Typical Data Encryption
Method
Wi-Fi Protected Access with Pre-
Shared Keys (WPA-PSK)
Small Office/Home
Office (SOHO)None NO
YES Uses WPA
encryption key to authenticate to
network
WPA
Password-based wireless network
securitySmall to medium
organization
Internet Authentication Services (IAS)
Certificate required for the
IAS server
NO However, a
certificate is issued to validate the IAS
server
YES WPA or Dynamic WEP
Certificate-based wireless network
securityMedium to large
organization
Internet AuthenticationServices (IAS)
CertificateServices
YES
NO Certificates used
but may be modified to require
passwords
WPA or Dynamic WEP
Agenda• Overview of Wireless Solutions• Securing a Wireless Network• Implementing a WLAN Using Password
Authentication• Configuring Wireless Network
Infrastructure Components• Configuring Wireless Network Clients
Effective Authentication and AuthorizationStandard Description
Extensible Authentication Protocol-Transport Layer Security (EAP-TLS)
Uses public key certificates to authenticate clients
Protected Extensible Authentication Protocol-Microsoft-Challenge Handshake Authentication
Protocol v2 (PEAP-MS-CHAP v2)
A two-stage authentication method using a combination of TLS and MS-CHAP v2 for password authentication
Tunneled Transport Layer Security (TTLS)A two-stage authentication method similar to PEAPMicrosoft does not support this method
Wireless data encryption standards in use today include:• Wired Equivalent Privacy (WEP)
• Dynamic WEP, combined with 802.1X authentication, provides adequate data encryption and integrity
• Compatible with most hardware and software devices• H ow is this a “wired equivalent”?! T rust m e: WEP sucks!
• Wi-Fi Protected Access (WPA/WPA2)• Changes the encryption key with each packet• Uses a longer initialization vector • Adds a signed message integrity check value• Incorporates an encrypted frame counter• WPA uses TKIP, WPA2 uses AES
Protecting WLAN Data Transmissions
System Requirements for 802.1X
Components Requirements
Client devicesWindows XP and Pocket PC 2003 provide built-in supportMicrosoft provides an 802.1X client for Windows 2000 operating systems
RADIUS/IAS and certificate servers
Windows Server 2003 Certificate Services and Windows Server 2003 Internet Authentication Service (IAS) are supported
Wireless access points
At a minimum, should support 802.1X authentication and 128-bit WEP for data encryption
• Require data protection for all wireless communications
• Require 802.1X authentication to help prevent spoofing, wardrivers, and accidental threats to your network
• Use tools to locate and shut down rogue access points on your corporate network:• “O ver the A ir” - Disassociation attack on rogue APs• “O ver the W ire” – Automatic switch port shutdown
Guidelines for Securing Wireless Networks
Agenda• Overview of Wireless Solutions• Securing a Wireless Network• Implementing a WLAN Using Password
Authentication• Configuring Wireless Network
Infrastructure Components• Configuring Wireless Network Clients
Components for PEAP-MS-CHAP v2
Components Explanation
Wireless ClientRequires a WLAN adapter that supports 802.1X and dynamic WEP or WPA encryptionUser and computers accounts are created in the domain
Wireless Access Point
Must support 802.1X and dynamic WEP or WPA encryptionThe wireless access point and RADIUS server have a shared secret to enable them to securely identify each other
RADIUS/IAS Server
Uses Active Directory to verify the credentials of WLAN clientsMakes authorization decisions based upon an access policyMay also collect accounting and audit informationCertificate installed to provide server authentication
Agenda• Overview of Wireless Solutions• Securing a Wireless Network• Implementing a WLAN Using Password
Authentication• Configuring Wireless Network
Infrastructure Components• Configuring Wireless Network Clients
Preparing the Environment
Install the WLAN Scripts using:• Microsoft WLAN-PEAP.msi
Install the additional tools on the IAS servers:• Group Policy Management Console• CAPICOM• DSACLs.exe
Configuring the Certification Authority
• The CA is used to issue Computer Certificates to the IAS Servers
• To install Certificate Services, log on with an account that is a member of:• Enterprise Admins• Domain Admins
• Consider that Certificate Services in Window Server 2003 Standard Edition does not provide:• Auto enrollment of certificates to both computers and users• Version 2 certificate templates • Editable certificate templates • Archival of keys
Certificate Templates Available: Computer (Machine)Drive and path of CA request files: C:\CAConfigLength of CA Key: 2048 bitsValidity Period: 25 yearsValidity Period of Issued Certificates: 2 yearsCRL Publishing Interval: 7 daysCRL Overlap Period: 4 days
Reviewing the CA Installation Parameters
1. Run MSSsetup CheckCAenvironment2. Run MSSsetup InstallCA3. Run MSSsetup VerifyCAInstall4. Run MSSsetup ConfigureCA5. Run MSSSetup ImportAutoenrollGPO6. Run MSSsetup VerifyCAConfig
• Y ou can do all this in the G U I… .but w hy?
Installing the Certification Authority
Configuring the Certification Authority
Install CA
Configuring Post-Installation Settings
Importing the Automatic Certificate Request GPO
Verifying the Configuration
demo
Internet Authentication Service (IAS) uses Active Directory to verify and authenticate client credentials and makes authorization decisions based upon configured policies.
IAS configuration categories include:• IAS Server Settings• IAS Access Policies• RADIUS Logging
Configuring IAS
IAS parameters that are to be configured include:• IAS Logging to Windows Event Log• IAS RADIUS Logging• Remote Access Policy• Remote Access Policy Profile
Are we going to script this?! Yes Sir!!!
Reviewing IAS Configuration Parameters
Configuring the IAS ServerValidating the IAS Environment
Verifying IAS Server Certificate Deployment
Post-Installation Configuration Tasks
Modifying the WLAN Access Policy Profile Settings
Verifying the Connection Request Policy for WLAN
Exporting the IAS Settings
demo
Configure the basic network settings such as :• IP configuration of the access point • Friendly name of the access point • Wireless network name (SSID)
Typical Settings for a Wireless Access Point include:• Authentication parameters• Encryption parameters• RADIUS authentication• RADIUS accounting
WAP Configuration Parameters
Wireless Access Point Configuration
Adding Access Points to the Initial IAS Server
Configuring Wireless Access Pointsdemo
Agenda• Overview of Wireless Solutions• Securing a Wireless Network• Implementing a WLAN Using Password
Authentication• Configuring Wireless Network
Infrastructure Components• Configuring Wireless Network Clients
Controlling WLAN AccessUsing Security Groups
Security Group Default Members
Wireless LAN AccessWireless LAN UsersWireless LAN Computers
Wireless LAN Users Domain Users
Wireless LAN Computers Domain Computers
IAS enables you to control access to the wireless network using Active Directory security groups that are linked to a specific remote access policy
Reviewing WLAN Client Parameters
Parameter Setting
Group to allow WLAN access Wireless LAN Access
Group to allow WLAN access for users Wireless LAN Users
Group to allow WLAN access for computers Wireless LAN Computers
WLAN GPO Name WLAN Client Settings
GPO filtering security group Wireless LAN Computer Settings
Wireless network policy name Windows XP WLAN Client Settings (PEAP-WEP)
WLAN network name (SSID) CONTOSO (change this to your SSID)
EAP type PEAP
PEAP authentication method Secured Password (EAP-MSCHAP v2)
PEAP fast reconnect Enabled
• There are bad people out there who want your WLAN, but you can deploy it securely!
• D eterm ine your organization’s w ireless requirem ents• Require 802.1X authentication• Implement the PEAP and Passwords solution for
organizations that do not utilize a PKI infrastructure• Use the scripts provided by the PEAP and Passwords
solution• Use security groups and Group Policy to control WLAN client
access• (… .and stop kidding yourself w ith W E P )
Session Summary