Lecture 7 Wireless and mobile network security

What are the 5 phases of the 802.11 RSN operation used to establish a RSNA.

- Phase 1: Discovery. The STA identifies an AP for a WLAN with which it wishes to communicate. The STA locates an AP either by receiving one of the AP's periodic transmissions of Beacon frames, or by sending a Probe Request to solicit a Probe Response from an AP. After the STA has identified an AP, the STA and the AP exchange frames to negotiate various parameters for their communications. By the end of the phase, the STA and AP have established a security policy that specifies several key security capabilities, such as data confidentiality and integrity protocols for protecting traffic, an authentication method, and a key distribution approach. - Phase 2: During this phase, the STA and AS prove their identities to each other. The authentication frames pass through the AP, which also blocks non-authentication traffic from the STA using IEEE 802.1X port-based access control. The actual authentication mechanism is implemented by the STA and AS using EAP, which provides a framework that allows the use of multiple methods for achieving authentication, including static passwords, dynamic passwords, and public key cryptography certificates. After authentication has been completed, the AAA key is installed in the STA and AS; it serves as a root key to enable the generation of other keys used to secure communications between the STA and AP. - Phase 3: Key Generation and Distribution (KGD). During the KGD phase, the AP and the STA perform several operations that cause cryptographic keys to be generated and placed on the AP and the STA. The KGD phase employs two types of handshakes: a 4-Way Handshake and a Group Key Handshake. Both employ message encryption and integrity checking, using one of two confidentiality and integrity algorithms. For both types of handshakes, NIST requires the use of AES Key Wrap with HMAC-SHA-1-128 instead of RC4 encryption with HMAC-MD5 because AES and SHA-1 are FIPS-approved algorithms, and RC4 and MD5 are not. - Phase 4: Protected Data Transfer. Frames are exchanged between the STA and the end station through the AP. As denoted by the shading and the lock and key, secure data transfer occurs between the STA and the AP only; security is not provided end-to-end. - Phase 5: Connection Termination. The AP and STA exchange frames. During this phase, the secure connection is torn down and the connection is restored to the original state.

What is the Media Access Control (MAC) address for the STA for the STA?

A MAC address is a (hopefully) unique 48-bit value that is permanently assigned to a particular wireless network interface. Many implementations of IEEE 802.11 allow administrators to specify a list of authorized MAC addresses; the AP will permit devices with those MAC addresses only to use the WLAN. This is known as MAC address filtering. However, since the MAC address is not encrypted, it is simple to intercept traffic and identify MAC addresses that are allowed past the MAC filter. Unfortunately, almost all WLAN adapters allow applications to set the MAC address, so it is relatively trivial to spoof a MAC address, meaning attackers can gain unauthorized access easily.

What is Counter Mode with Cipher Block Chaining Mac Protocol (CCMP)?

CCMP is the second data confidentiality and integrity protocol that may be negotiated as a cipher suite for the protection of user traffic in an RSNA. Like TKIP, CCMP was developed to address all known inadequacies of WEP; however, CCMP was developed without the constraint of requiring the use of existing hardware. CCMP is considered the long-term solution for the creation of RSNs for WLANs. It is mandatory for RSN compliance.

The last phase of the RSN operation is Connection Termination. Describe it.

During this phase, the association between the STA and the AP is deleted, and the wireless connection is terminated. This phase provides the elegant teardown of a connection and a restoration to an initialized state. During the connection termination phase, the following events occur: - The AP deauthenticates the STA. - The security associations, used internally by the AP to keep track of associations between STAs and APs, are deleted. - The temporal keys used for encrypting and protecting the integrity of data traffic are deleted. - The IEEE 802.1X controlled port returns to a blocked state so that user traffic cannot pass.

What is emission security?

Emission security is concerned with loss of confidentiality due to unintended compromising emanations: • Data may be reconstructed from electromagnetic emanations from monitors, computers, and other electrical devices • Such emanations may also be amplified by a nearby radio transmitter, such as a WLAN or cell phone • Leakage of information may also occur through sound or vibration - Most electronic devices emit electromagnetic radiation (not intentionally). - This radiation can be used by an opponent to gain privileged information, or disrupt the functionality of the device. - An opponent could also use other signals coming in or out of an electronic device (such as power or clock cycles). - All these are referred to as emanations.

Describe the Key Generation and Distribution Phase during a RSN operation.

Following the successful completion of the authentication phase, the STA and AP perform a series of functions that position cryptographic keys in both entities. This phase is called the key generation and distribution (KGD) phase. It provides the final step in authentication and allows the STA and AP to derive keys that make secure data transfer possible. The KGD phase has several purposes, including confirming the existence of a Pairwise Master Key, ensure keys are new, confirm cipher suit selection. The KGD phase includes two types of handshakes: a 4-Way Handshake and a Group Handshake. The Group Handshake is necessary only when STAs participate in multicast or broadcast traffic. The purpose of this handshake is to provide message integrity checking and to protect against tampering, and message encryption.

What is a Key Reinstallation Attack?

Forcing Nonce Reuse in WPA2 • Replay of handshake message results in key being reinitialized, including resetting nonce/IV - resulting in reuse of the keystream • CCMP: attacker can replay and decrypt packets • GCMP: Attacker can replay and decrypt packets, and forge packets in both Directors. All protected Wi-Fi networks use the 4-way handshake to generate a fresh session key. So far, this 14-year-old handshake has remained free from attacks, and is even proven secure. However, we show that the 4-way handshake is vulnerable to a key reinstallation attack. Here, the adversary tricks a victim into reinstalling an already-in-use key. This is achieved by manipulating and replaying handshake messages. When reinstalling the key, associated parameters such as the incremental transmit packet number (nonce) and receive packet number (replay counter) are reset to their initial value.

What is GSM (2G)?

GSM (2G) aimed to provide security equivalent to a wired network. Subscriber Identity Module (SIM): • IMSI (International Mobile Subscriber Identification) • Subscriber authentication key (128 bit) - used for one-way authentication of the subscriber to the network • PIN Uses Temporary Mobile Identification (TMSI) to provide location security (i.e., limit exposure of IMSI) - circumvented by IMSI catchers

How can you crack WPA/WPA2-PSK? And how to protect against cracking?

Given a weak passphrase, brute force or dictionary attacks are fully practical against WPA/WPA2-PSK. - Choose a strong passphrase (e.g., xFe>RLv6&s=@Q6q%&- 'q7CGdI9) - May use an uncommon SSID to mitigate use of rainbow tables in dictionary/brute-force attacks to find PMK/PTK (PSK is generated from SSID and password)

What is the IEEE 802 protocol and what is the 802 MAC PDU?

IEEE 802 is a family of IEEE standards dealing with local area networks and metropolitan area networks. More specifically, the IEEE 802 standards are restricted to networks carrying variable-size packets. By contrast, in cell relay networks data is transmitted in short, uniformly sized units called cells. Isochronous networks, where data is transmitted as a steady stream of octets, or groups of octets, at regular time intervals, are also out of the scope of this standard. A MAC PDU is known as a MAC frame. Each MAC frame starts with a fixed-length MAC header. This header may be followed by the payload of the MAC PDU (MPDU). A MPDU may contain a CRC (Cyclic Redundancy Check).

What is infrastructure mode in 802.11 WLAN? And describe the components inside!

In infrastructure mode (ESS), an IEEE 802.11 WLAN comprises one or more Basic Service Sets (BSS), the basic building blocks of a WLAN. A BSS includes an AP and one or more STAs. The AP in a BSS connects the STAs to the DS. The DS is the means by which STAs can communicate with the organization's wired LANs and external networks such as the Internet. The DS and use of multiple BSSs and their associated APs allow for the creation of wireless networks of arbitrary size and complexity. - Station (STA). A STA is a wireless endpoint device, such as a laptop, PDA, or mobile phone. - Access Point (AP). An AP logically connects STAs with a distribution system, which is typically an organization's wired network infrastructure. APs can also logically connect wireless STAs with each other without accessing a distribution system. - Basic Service Set (BSS). A BSS is composed of an AP and one or more STAs configured in infrastructure mode. Each of the STAs associate directly with the AP. A BSS is the basic building block of a WLAN. - Distribution System (DS). A DS is an infrastructure, typically a wired LAN, that connects individual BSSs to each other.

What are the two attack types with wireless?

In wireless networks, attacks can be performed with low risk from a distance without access to network components. Passive attacks (non-invasive and basically impossible to detect) - Eavesdropping - Traffic analysis Active attacks (hard to trace) - Masquerade (including rogue AP) - Replay - Message modification - Denial of service (including jamming) - Unauthorized use (misappropriation)

What is the IEEE 802.11i amendment?

It introduces the concept of Robust Security Network (RSN). An RSN is defined as a wireless security network that only allows the creation of Robust Security Network Associations (RSNA). An RSNA is a logical connection between communicating IEEE 802.11 entities established through the IEEE 802.11i key management scheme, called the 4-Way Handshake, which is a protocol that validates that both entities share a pairwise master key (PMK), synchronizes the installation of temporal keys, and confirms the selection and configuration of data confidentiality and integrity protocols. The entities obtain the PMK in one of two ways—either the PMK is already configured on each device, in which case it is called a pre-shared key (PSK), or it is distributed as a side effect of a successful EAP authentication instance, which is a component of IEEE 802.1X port-based access control. The PMK serves as the basis for the IEEE 802.11i data confidentiality and integrity protocols that provide enhanced security over the flawed WEP.

What is the IEEE 802.1X standard?

It is specified by the IEEE 802.11i amendment. The IEEE 802.1X standard provides a framework for access control that leverages EAP to provide centralized, mutual authentication. The IEEE 802.1X framework provides the means to block user access until authentication is successful, thereby controlling access to WLAN resources. The IEEE 802.11i amendment allows for enhanced security features beyond WEP and the simple IEEE 802.11 shared key challenge-response authentication.

Does Disabling of identifier (SSID) broadcasting and MAC address filtering provide protection?

It provides negligible protection. An implication of disabling SSID broadcasting at access points is that clients periodically must send queries for the SSID to discover it - The client machine may become more exposed and an attacker is able to discover the SSID anyway MAC addresses are sent unencrypted and are easy to spoof

Describe the pairwise key hierarchy used during a RSNA during authentication and key generation. There are two ways in which keys may be installed. Describe them too.

Pairwise is designed for unicast traffic. - Pre-Shared Key (PSK), which is a static key delivered to the AS and the STA through an out-of- band mechanism. The IEEE 802.11 standard does not specify how PSKs are to be generated or distributed, so these decisions are left to implementers. The security of the WLAN is compromised if any of the PSKs does not possess sufficient cryptographic strength. As a result, organizations should review any PSK approach carefully for possible vulnerabilities and evaluate its performance implications. Distributing PSKs in a large network might be infeasible. - Authentication, Authorization, and Accounting (AAA) Key (AAAK), also known as the Master Session Key (MSK), which is delivered to the AP through the Extensible Authentication Protocol (EAP) during the process of establishing an RSNA. Each time a user authenticates to the WLAN, the AAA key changes; the new key is then used for the duration of the user's session.

What is Pre-shared key (PSK)?

Pre-Shared Key (PSK), which is a static key delivered to the AS and the STA through an out-of- band mechanism. The IEEE 802.11 standard does not specify how PSKs are to be generated or distributed, so these decisions are left to implementers. The security of the WLAN is compromised if any of the PSKs does not possess sufficient cryptographic strength. As a result, organizations should review any PSK approach carefully for possible vulnerabilities and evaluate its performance implications. Distributing PSKs in a large network might be infeasible.

With the addition of the IEEE 802.11i, IEEE 802.11 offers two general classes of security capabilities for IEEE 802.11 WLANs. The first class, pre-RSN security, includes the legacy security capabilities developed in the original IEEE 802.11 specification: open system or shared key authentication for validating the identity of a wireless station, and WEP for the confidentiality protection of traffic. The second class of security capabilities includes a number of security mechanisms to create RSNs. Describe the RSN and its three features.

RSN's security features apply only to the wireless portion of the overall network, not to communications on wired networks. The RSN provides these three features - Access control: this is provided through the iEE 802.1X port-based access control. The RSNA relies on this to provide an authentication framework. - Authentication and key generation: This is provided through the EAP, a means to providing mutual authentication between STAs and the WLAN infrastructure, as well as performing automatic cryptographic key distribution. - Confidentiality, Data origin authentication and integrity and replay protection: This is provided either through the TKIP (WPA1) or CCMP (WPA2). TKIP was created to allow already-deployed devices to address the numerous inadequacies of WEP.

What are some alternative protocols for 802.11i Protected Data Transfer Phase.

Temporal Key Integrity Protocol (TKIP) (optional) - Only software changes from WEP in order to support legacy devices - RC4 encryption, with new key for each frame - Transition solution - Also known as WPA Counter mode with CBC-MAC Protocol (CCMP) - Confidentiality, message authentication, and replay prevention - AES based (128-bit key) - Provides stronger security than TKIP - Also known as WPA2 Galois Counter Mode Protocol (GCMP) is not part of the 802.11i specification, but was introduced later (including GCMP-256 in WPA3)

What is Darkhotel APT?

That is attacks on selected high profile guests using hotel networks. • Guest entered last name and room number to access network • Login portal was used to redirect to the phony installers who informed user to install software update • Update contained digitally signed Darkhotel backdoors - Broke weak certificates (512-bit keys) - Also used 2048-bit certificates, stolen?

What is TKIP?

TKIP is a cipher suite for enhancing the WEP protocol on pre-RSN hardware without causing significant performance degradation. TKIP provides the following fundamental security features for IEEE 802.11 WLANs: - Confidentiality protection using the RC4 algorithm - Integrity protection against several types of attacks using the Michael message digest algorithm (through generation of a message integrity code. - Replay prevention through a frame sequencing technique

The IEEE 802.11i amendment defines an RSN as a wireless network that allows the creation of RSN Associations (RSNA) only. An RSNA is a security relationship established by the IEEE 802.11i 4-Way Handshake. Briefly describe the 4-way handshake.

The 4-Way Handshake validates that the parties to the protocol instance both possess a pairwise master key (PMK), synchronizes the installation of temporal keys, and confirms the selection of cipher suites. The PMK is the cornerstone for a number of security features absent from WEP. With RSNAs there are several inter-related keys that underlie the security functions of encryption, authentication, and integrity. IEEE 802.11i defines two key hierarchies for RSNAs that specify the inter-relations of the keys. The two key hierarchies are the Pairwise Key Hierarchy, which is designed for unicast traffic protection, and the Group Key Hierarchy, which is intended for multicast/broadcast traffic protection

For data confidentiality and integrity protection, RSN provides two protocols. Name and describe them!

The IEEE 802.11i amendment defines two RSNA data confidentiality and integrity protocols: Temporal Key Integrity Protocol (TKIP) and Counter Mode with Cipher Block Chaining MAC Protocol (CCMP). TKIP was created to allow already-deployed devices to address the numerous inadequacies of WEP. However, because TKIP uses RC4 and the Michael message integrity code (MIC), both of which have known weaknesses, TKIP is not suitable for high assurance environments. For these environments, CCMP is considered the better solution. However, CCMP requires computing resources that cannot be assumed on pre-RSN hardware. TKIP: TKIP is intended as an interim solution for IEEE 802.11 WLANs to address the numerous inadequacies of WEP expeditiously. Uses RC4 algorithm, which uses a 24-bit IV which is too small to prevent recurring IV's on a busy WLAN. CCMP (also known as WPA2): CCMP is the second data confidentiality and integrity protocol that may be negotiated as a cipher suite for the protection of user traffic in an RSNA. Like TKIP, CCMP was developed to address all known inadequacies of WEP; however, CCMP was developed without the constraint of requiring the use of existing hardware. It uses the AES with 128-bit block size.

What is a RSNA?

The RSN is a security network that only allows the creation of robust security network associations (RSNAs), which are a type of association used by a pair of stations (STAs) if the procedure to establish authentication or association between them includes the 4-Way Handshake.

What is a Service Set Identified (SSID)? for the AP?

The SSID is a name assigned to a WLAN; it allows STAs to distinguish one WLAN from another. SSIDs are broadcast in plaintext in wireless communications, so an eavesdropper can easily learn the SSID for a WLAN. However, the SSID is not an access control feature, and was never intended to be used for that purpose.

Describe the Discovery Phase in a RSN operation.

The discovery phase is the first phase in the process to establish RSNAs. During this phase, STAs discover the existence of a network with which to communicate. STAs locate and identify APs through the APs' periodic transmission of Beacon frames. During the discovery phase, STAs and APs negotiate several things, including the SSID, supported data rates, and other technical operating parameters related to reliable communication, as well as a security policy. In general, 802.11i does not support extensive negotiation The AP describes the options that it supports, and only clients that are configured for compatible options will attempt to connect. Many APs and STAs can only store a single configuration at a time. They establish confidentiality and integrity protocols, autoehltncaiton methods, crypto approach, and pre-authentication capabilities.

Wi-Fi Protected Access (WPA) 3 was standardized in 2018 by the Wi-Fi alliance. Explain its three features!

The new standard uses 128-bit encryption in WPA3-Personal mode (192-bit in WPA3-Enterprise) and forward secrecy. The WPA3 standard also replaces the Pre-Shared Key exchange with Simultaneous Authentication of Equals as defined in IEEE 802.11-2016 resulting in a more secure initial key exchange in personal mode. It has three features: Requires protected management frames. This feature protects stations against forged management frames spoofed from other devices that might otherwise disrupt a valid user session. MFP is negotiated between the client and AP. WPA3-SAE (Simultaneous Authentication of Equals). In cryptography, Simultaneous Authentication of Equals (SAE) is a secure password-based authentication and password-authenticated key agreement method WPA3-Enterprise 192-bit mode - (EC)DHE key exchange, using RSA or ECDSA for authentication - AES256-GCM (GCMP-256) for authenticated encryption - HMAC-SHA384 for key derivation and confirmation

What are the components of the IEEE 802.11?

The two primary component are: - Station (STA). A STA is a wireless endpoint device. Typical examples of STAs are laptop computers, personal digital assistants (PDA), mobile phones, and other consumer electronic devices with IEEE 802.11 capabilities. - Access Point (AP). An AP logically connects STAs with a distribution system (DS), which is typically an organization's wired infrastructure. APs can also logically connect wireless STAs with each other without accessing a distribution system. The IEEE 802.11 standard also defines the infrastructure mode.

Describe the authentication phase of an RSN operation.

This phase provides the means for a STA to prove its identity to the WLAN. This security service is critical for preventing unauthorized access to network resources. In an infrastructure WLAN, authentication provides protection against unauthorized users in the DS, since the AP is the entry point into the ESS. Improper authentication can undermine all security measures in an enterprise. Mutual authentication also allows the WLAN to prove its identity to the STA, which allows the STA to validate positively that it is communicating with a legitimate WLAN, as opposed to an unauthorized or "rogue" WLAN. The authentication occurs between the STA and the AS, which is located in the DS. This authentication procedure is designed to disallow all stations from using the network except for those that are explicitly authorized to do so. It also provides a level of confidence to the STA's user that the STA is communicating with the legitimate network. IEEE 802.11 standard uses the IEEE 802.1X standard to provide mutual authentication between STAs and ASs. IEEE 802.1X authentication has three main components: a client (also known as a supplicant), an authenticator, and an AS. The authenticator simply passes authentication traffic between the client and AS. At the conclusion of the authentication dialog, the AP controlled port is still blocked to general user traffic. Although the authentication is successful, the ports remain blocked until the temporal keys are installed in the STA and AP, which occurs during the 4-Way Handshake. This blocking keeps unauthorized traffic from entering the DS and prevents any traffic from the DS from being transmitted wirelessly. After the seven-step authentication process has been completed, the AAA key is installed in the STA and the AS. As discussed in Section 4.2.1, the AAA key serves as a root key to enable the generation of other keys used to secure communications between the STA and the AP. The AAA key for this particular STA is the foundation of security, and its compromise would be devastating to the overall security of the system.

Explain port-based access control in the IEEE 802.1X standard.

Until successful authentication occurs between a STA and the AS, the STA's communications are blocked by the AP. Because the AP sits at the boundary between the wireless and wired networks, this prevents the unauthenticated STA from reaching the wired network. IEEE 802.1X can control data flows by distinguishing between EAP and non-EAP frames, then passing EAP frames through an uncontrolled port and non-EAP frames through a controlled port, which can block access. IEEE 802.11i extends this to block the AP's communication until keys are in place as well.

What is WPA3-Simultaneous Authentication of Equals (SAE)?

WPA3-Simultaneous Authentication of Equals (SAE) is a major improvement from WPA2-Personal/PSK • The attacker can only make one password guess per attack - The only information the attacker gains is whether this guess is corrector not - Cannot perform dictionary/brute-force attacks off-line - Gains no information about password through eavesdropping • Forward secrecy - compromise of the password will not disclose previous communication • Compromise of shared (session) secret won't help attacker in later sessions • A variation of a the password authenticated key-exchange Dragonfly

What is Wi-fi protected setup (WPS)?

Wi-Fi Protected Setup (WPS): providing easy WPA/WPA2 key configuration for Alice, Bob.....and Eve. • 8 digit PIN, where last digit is checksum • The validity of the first and second half is acknowledged independently • Depending on implementation: unrestricted number of PIN attempts Wi-Fi Protected Setup (WPS; originally, Wi-Fi Simple Config) is a network security standard to create a secure wireless home network. The goal of the protocol is to allow home users who know little of wireless security and may be intimidated by the available security options to set up Wi-Fi Protected Access, as well as making it easy to add new devices to an existing network without entering long passphrases. Prior to the standard, several competing solutions were developed by different vendors to address the same need.

How has security in WLAN evolved from WEP to WPA2/IEEE 802.11i?

Wired Equivalent Privacy (WEP) - part of 802.11 standard (1999) - Flawed authentication. Pre-RSN IEEE 802.11 performs access control through either open system or shared key authentication. Open system authentication does not verify any claimed credentials from the STA, so it is generally suitable only for providing public access to a WLAN. - Weak/flawed encryption(key reuse due to 24-bit IV) - Flawed integrity (RC4 encrypted CRC). WEP attempts to perform data integrity checking for messages and reject messages that have been changed in transit. WEP uses a simple non-cryptographic checksum to detect errors in data transmission and protects this checksum with a stream cipher. Unfortunately, stream ciphers offer no protection against bit-flipping attacks, which means that in many cases a determined adversary can alter both data and the corresponding checksums without detection. WPA (Wi-Fi Protected Access) interoperability certification (2003) - Interim solution based on subset of 802.11i draft - Based on WEP, but using Temporal Key Integrity Protocol (TKIP) IEEE 802.11i standard (2004) - Robust Security Network - Amendment to 802.11 standard - CCMP(AES)

How do wireless networks pose a threat to wired networks?

Wireless devices may also pose a vulnerability to wired networks by introducing uncontrolled connections. Where relevant, dual connections should automatically be disabled (combining networks into one).

What is the WI-fi Enhanced Open - Opportunistic Wireless Encryption (OWE) for open networks?

Wi‑Fi CERTIFIED Enhanced Open is a Wi-Fi Alliance certification that preserves the convenience open networks offer while reducing some of the risks associated with accessing an unsecured network. Wi-Fi Enhanced Open networks provide unauthenticated data encryption to users, an improvement over traditional open networks with no protections at all. These protections are transparent to the user. • Opportunistic Wireless Encryption (RFC8110) - as an alternative to sending in cleartext • Based on the use of unauthenticated Diffie-Hellman - Does not protect against active attackers (e.g., fake AP) • Provides protection against passive attackers - Unique PMK for each connection, as opposed to WPA2-Personal when the same PSK is (openly) shared • Not part of the current WPA3 specification - but likely to be supported by many WPA3 devices/products

What are the 3G security advantages compares to 2G?

• All keys are 128 bit • Two-way authentication • Protects integrity (in addition to confidentiality) of both message content and signaling between mobile and operator network May perform downgrade attack to GSM (2G) unless disabled Long Term Evolution (LTE/LTE-A/4G) evolves towards all-IP- networks (including the use of IPsec)...but still doesn't ensure end-to-end security

How do Mobile and wireless devices may pose an increased security risk?

• Lack of physical security controls - may be easier for an attacker to steal, tamper with, or access a mobile device • Untrusted mobile devices (e.g., employees personal devices not controlled by the organization) and use of applications created by unknown parties • Use of untrusted networks - e.g., more susceptible to eavesdropping and MITM attacks and exposure to untrusted content - e.g., mobile devices may be exposed to other content (e.g., QR codes identifying a URL) than other computing devices • Interaction with other systems - e.g., automatic device synchronization may result in data being stored in untrusted external location • Multiple sensors (microphone, camera, accelerometer, GPS/location, wireless radio receiver,...)

Why is Monitoring and auditing is an important part of WLAN security (and network security in general)?

• Unauthorized WLAN devices (AP and STA) • WLAN devices that are misconfigured or use weak protocols/implementations • Unusual usage patterns, e.g., - Abnormally high volumes of WLAN traffic involving a particular client device - Many failed attempts to join the WLAN in a short period of time • Active WLAN scanners • DoS attacks • Masquerade (e.g., address spoofing)

Provide a summary of wireless network security

• WPA2 (i.e,. CCMP / AES) is a minimum for securing WLANs today • PSK is not suitable/scalable beyond home networks • WPA3 provides significant security improvements • WLAN monitoring can be used for additional control