A basic SYN flood attack is a type of denial-of-service (DoS) attack that aims to exhaust the resources of a server by sending a large number of SYN packets and not completing the TCP three-way handshake. The intent of this attack is to exceed the threshold limit of the connection queue, which is the data structure that stores the information about the pending connections. By doing so, the attacker prevents legitimate clients from establishing connections with the server, as the server cannot accept any more SYN requests. A SYN flood attack can be performed with spoofed IP addresses or without IP spoofing, depending on the attacker's strategy and the server's configuration. References: [Implementing and Operating Cisco Security Core Technologies (SCOR) v1.0], Module 3: Securing Networks with Firewalls, Lesson 3.2: Firewall Technologies,

Explanation Explanation Cisco IOS public key infrastructure (PKI) provides certificate management to support security protocols such as IP Security (IPSec), secure shell (SSH), and secure socket layer (SSL). This module identifies and describes concepts that are needed to understand, plan for, and implement a PKI. A PKI is composed of the following entities: ... - A distribution mechanism (such as Lightweight Directory Access Protocol [LDAP] or HTTP) for certificate revocation lists (CRLs) Reference: https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/sec_conn_pki/configuration/15-mt/sec-pki-15-mtbook/sec-pki-overview.html Explanation Cisco IOS public key infrastructure (PKI) provides certificate management to support security protocols such as IP Security (IPSec), secure shell (SSH), and secure socket layer (SSL). This module identifies and describes concepts that are needed to understand, plan for, and implement a PKI.
A PKI is composed of the following entities: ...
- A distribution mechanism (such as Lightweight Directory Access Protocol [LDAP] or HTTP) for certificate revocation lists (CRLs) Explanation Explanation Cisco IOS public key infrastructure (PKI) provides certificate management to support security protocols such as IP Security (IPSec), secure shell (SSH), and secure socket layer (SSL). This module identifies and describes concepts that are needed to understand, plan for, and implement a PKI. A PKI is composed of the following entities: ... - A distribution mechanism (such as Lightweight Directory Access Protocol [LDAP] or HTTP) for certificate revocation lists (CRLs) Reference: https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/sec_conn_pki/configuration/15-mt/sec-pki-15-mtbook/sec-pki-overview.html

A posture policy is a collection of posture requirements, which are associated with one or more identity groups, and operating systems. We can configure ISE to check for the Windows patch at Work Centers > Posture > Posture Elements > Conditions > File.
In this example, we are going to use the predefined file check to ensure that our Windows 10 clients have the critical security patch installed to prevent the Wanna Cry malware.

SSL decryption allows the intelligent proxy to inspect traffic over HTTPS. Some websites may use self-signed certificates or certificates that are not trusted by the user's device. This may cause the browser to display a warning or an error message when accessing those websites through the intelligent proxy. To avoid this, the user's device needs to trust the Umbrella root CA, which is the certificate authority that signs the certificates for the websites that are proxied by Umbrella. By importing the Umbrella root CA into the trusted root store on the user's device, the browser will recognize the certificates as valid and will not alert the end-users12. References: 1: Enable SSL Decryption - Umbrella User Guide 2: Intelligent Proxy and SSL Decryption with Cisco Umbrella

https://www.cisco.com/c/dam/en_us/about/doing_business/legal/service_descriptions/docs/Cisco_Secure_Managed_Endpoint.pdf