> For the complete documentation index, see [llms.txt](https://derek-johnson-1.gitbook.io/welcome/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://derek-johnson-1.gitbook.io/welcome/projects/security+-notes.md).

# Security+ Notes

#### Forensic techniques

* **Chain of custody** - Chronological documentation of the handling, transfer, and location of digital evidence.
* **Non-repudiation** - ensures the integrity and authenticity of a message or transaction. The ability to prove that a specific action or event occurred, and certain parties participated.

**SSL Certs** - Certificates that are used to encrypt traffic between a client and a server.

**WAF** - Web application firewall

**DHCP** - Dynamic host configuration protocol is a network protocol used to automatically assign IP addresses and other network configuration settings. 

* DHCP Server: A DHCP server is a device or server within a network that is responsible for managing and allocating IP addresses and configuration parameters. The server holds a pool of available IP addresses that it can assign to devices.
* DHCP Discovery: When a device (referred to as a DHCP client) connects to a network, it sends out a DHCP discovery message, usually as a broadcast, to locate a DHCP server.
* DHCP Offer: Upon receiving the discovery message, DHCP servers respond with a DHCP offer. The offer includes an available IP address from the server's pool and other network configuration parameters.
* DHCP Request: The client selects one of the offered IP addresses and sends a DHCP request message to the server, confirming its intention to use the offered IP address and associated configurations.
* DHCP Acknowledgment: The DHCP server acknowledges the client's request by sending a DHCP acknowledgment message, also known as a DHCP ack. This message confirms the allocation of the IP address and provides the client with the lease duration (the time period for which the IP address is valid).
* DHCP Lease Renewal: DHCP leases are not permanent, and they have an expiration period. Before the lease expires, the client can request a lease renewal from the DHCP server. If granted, the lease is extended, and the client continues to use the assigned IP address and configurations.

Hardware root of trust -