Firewalls – Can be implemented as software as software running as an application on OS, might be built in to os, might be a network appliance. Comes in different forms. The job is to protect one portion of your network or computer system from another portion. Device connects to inside protected network from outside. outside network is usually the internet. ASA is a Cisco firewall. ASAv is a virtual version of that.
Access Points – connects users to network quickly and efficiently as possible with security. Usually dual band because they support frequency bands for various iterations of 802.11 wireless standards.
Wireless Controllers – Manages many access points in one environment. Brains of the operation and control aspects like security and frequency usage and antennae strength.
Wireless networks often use CSMA/CA – carrier sense multiple access with collision avoidance. Carrier sensing is used, but nodes try to avoid collisions by transmitting only when channel is sensed to be idle.
LAN with ethernet cables use carrier sense multiple access with collision detection. Listens to other signals while transmitting, if it detects that there are two sending at the same time, it stops transmitting, frame, then sends jam signal and waits for random time before resending.
Wireless Lan Controllers configure wireless policies, management, or security settings at anytime through centralized provisioning and management. Faster response to business needs by centrally managing wireless networks. Standardized access point configuration for software versioning. wireless intrusion prevention system capabilities, network wide qos for voice/video access wired/wireless networks, network wide centralized security policies across wired and wireless networks, mobility security and management for ipv6 and dual stack clients.