Structure of the Internet Flashcards
What is a tier 1 network?
Backbone cables connecting continents, where then large telecom companies connect together.
What is an Internet Exchange Point (IXP)?
Physical infrastructures where ISPs connect
What is a Point of Presence (POP)?
Places ISPs communicate with users
What is a tier 2 network?
ISPs that buy Internet transit from other providers to reach parties on the global internet.
What is Packet switching?
Sending of packets across a network where other similar communications are happening.
What does a router do?
Reads the destination IP of packets and forwards it to destination on the fastest least congested route.
What are the main components of packets?
- Header
- Source IP
- Destination IP
- Other metadata
- Payload
- Trailer with Cyclical Redundancy Check (optional)
What is a gateway?
A device that connects networks using different protocols
What is a router?
A device that connects 2 or more different networks
When should you use a router and when should you use a gateway?
Router: When networks have the same protocol
Gateway: When networks have different protocols
How is routing achieved?
A routing table is used to store the location of other network devices and the fastest route to them and is updated as needed
What is a uniform resource locator (URL)?
Full addresses for internet resources
What is a fully qualified domain name (FQDN)?
A domain name that includes host server name (i.e. www, mail, ftp)
What is an IP address?
A numerical label assigned to a device on a network.
How are domain names organised
Using internet registrars which are organisations that manage allocation and registration of IP addresses, domain names and other resources that must be unique.
