1.2 Network Devices & Functions

Switch

• Forwards traffic based on data link address

• OSI Layer 2 device

Router

• Routes traffic between IP subnets

• OSI Layer 3 device

Firewall

• Filters and encrypts traffic to protect the data and the network
• Most firewalls also function as a router

IDS

• Intrusion Detection System
• Watches network traffic for any malicious data or attacks
• Detection - Alarm or alert

IPS

• Intrusion Prevention System
• Watches network traffic for any malicious data or attacks
• Prevention - Stops it before it gets into the network

Load Balancer

• Distributes network activity across multiple servers

TCP Offloading

• Load balancing method
• Allows devices to connect to the server as quickly as possible

SSL Offloading

• Load balancing method
• Handles the encryption/decryption process so servers don't need to

Caching

• Load balancing method
• Common requests are stored on the load balancer so they are handled quickly

Proxies

• A server that sits between the user device and the outside network

NAS

• Network Attached Storage
• Shared storage device across the network
• File level access

SAN

• Storage Area Network
• Shred storage device across the network
• Block level access

AP

• Access Point
• A bridge that allows devices to wirelessly connect to the local network

Wireless LAN Controller

• Centralized management of APs across a network

CDN

• Content Delivery Network
• Geographically distributed caching servers

VPN

• Virtual Private Network
• Secure private data traversing a public network

Concentrator

• A dedicated encryption/decryption device used to create the VPN

QoS

• Quality of Service
• Configuration that controls the priority of different applications or services across a network

TTL

• Time To Live
• A timer that ensures that a network process doesn't go on forever