Network services Flashcards
WAN
Wide Area Network – connects 2 buildings
LAN
Local Area Network – all the devices sharing a gateway
NAT
Network Address Translation
What is Network Address Translation ?
Used to swap private/public IP addresses. Routers temporarily remove private IP address and store it in a table. Private IP address is replaced with router’s public ip address. On return trip process is reversed.
What is Port Forwarding ?
A technique that allows external devices access to computers on private networks
Access Control List
Filters IP addresses; blocks known bad IP addresses
What is Traffic Shaping ?
Gives priority to some traffic. Example, phone calls may get priority over web browsing.
DHCP
Dynamic Host Configuration Protocol
How does Dynamic Host Configuration Protocol work?
Device requests and IP address from DHCP server. DHCP server returns an offer with an IP address. Address is assigned to device. DHCP server creates a binding (record that is stored in a database and lists ip address and mac address).
URL
Uniform Resource Locator
Top Level Domain (TLD)
.com .edu .org
Second level domain
In www.pluralsight.com “pluralsight” is the 2nd level domain. Often referred to as “domain name”
Third level domain
www Often referred to as “host name”
Forward DNS lookup
Requesting device asks a DNS server for IP address of a url.
Reverse DNS lookup
Requesting device asks for domain of an IP address
