1.2 Networking Functions Flashcards
N10-009 Obj. 1.2 Compare and contrast networking appliances, applications, and functions (27 cards)
What is the purpose of a Content Delivery Network (CDN)?
To geographically distribute caches of content to users to reduce latency and load times.
Why does a CDN improve performance?
It places data closer to users, reducing the time required to access content from distant servers.
What types of services commonly use CDNs?
Video platforms (e.g., Youtube), large websites, global apps.
What is a Virtual Private Network (VPN)?
A secure, encrypted connection over an untrusted network like the Internet.
What is a VPN concentrator?
A device (hardware or software) that handles high-speed encryption/decryption for multiple VPN connections.
Where is VPN functionality often integrated today?
Into next-generation firewalls (NGFWs).
What type of VPN clients might a user need?
Vendor-specific software or built-in clients (Windows, macOS, Linux)
What is Quality of Service (QoS) used for in networking?
To prioritize certain types of network traffic over others.
Give an example of high priority traffic for QoS.
Real-time audio or video communication.
What devices can be configured to manage QoS?
Routers, switches, and firewalls.
What other terms are commonly associated with QoS?
Traffic shaping and packet shaping.
What is Time to Live (TTL) in networking?
The maximum number of hops a packet can take before being discarded by a router.
Why is TTL important?
It prevents routing loops by limiting how long a packet can exist on a network.
How is TTL represented in an IP packet?
As a field in the IP header that decrements by 1 at each router.
What happens when TTL reaches zero?
The router drops the packet.
What are the default TTL values for common OSs?
Windows: 128
macOS and Linux: 64
What is a routing loop?
A scenario where packets endlessly circulate between routers due to incorrect routing configurations.
How does TTL help in a routing loop situation?
It limits the number of hops to eventually stop the looping packet.
How can routing loops be detected?
Using traceroute; repeated IPs indicate looping paths.
How is TTL used in DNS?
It defines how long a DNS record is cached locally (in seconds).
What happens when the DNS TTL expires?
The cached record is deleted, and a new DNS lookup is performed.
What value indicates a DNS TTL of 5 minutes?
300 seconds
What device supports secure remote work through encrypted connections?
A VPN concentrator
What mechanism improves web application speed for users around the world?
Content Delivery Network (CDN)
