Explanation
Graphical user interface, application Description automatically generated

Explanation
From the neighbor status, we notice the "Flags" are SP. "P" here means the neighbor is in Passive mode.In order to create an Etherchannel interface, the (local) SW1 ports should be in Active mode.Moreover, the "Port State" in the exhibit is "0x3c" (which equals to "00111100 in binary format).Bit 3 is "1" which means the ports are synchronizing -> the ports are working so the local ports should be in Active mode.

Explanation
AAA stands for Authentication, Authorization and Accounting.+ Authentication: Specify who you are (usually via login username & password)+ Authorization: Specify what actions you can do, what resource you can access+ Accounting: Monitor what you do, how long you do it (can be used for billing and auditing)An example of AAA is shown below:+ Authentication: "I am a normal user. My username/password is user_tom/learnforever"+ Authorization: "user_tom can access LearnCCNA server via HTTP and FTP"+ Accounting: "user_tom accessed LearnCCNA server for 2 hours". This user only uses "show" commands.

Explanation
Most traditional devices use a distributed architecture, in which each control plane is resided in a networking device. Therefore they need to communicate with each other via messages to work correctly.In contrast to distributed architecture, centralized (or controller-based) architectures centralizes the control of networking devices into one device, called SDN controller