LECTURE 1

Section 1

DNS: DNS means Domain Name System.

Each end-system has an IP address

We can have 4 billion IP addresses
You can find your IP address by :http://www.tracerouters.org.
DNS finds the machine, but not the file.
File location? Uniform Resource Locator.
2 files can have different URLs for the same files, but the same DNS.
Cannot have different DNS, in the same URls.

Packet Switching: Packet switching relies on processsing and transmitting data in packet.
How the packets are constructed depends on the protocol used.
Each packet is transmitted from the source.
Each packet follows a logical path towards its destination.

IP Packet (click on image to view IP Packet diagram
Routing: Routers are devices that can exist in both Lan and Wan.
Routers can solve the problems of segmentation issues in LANs.
In WANs routers serve as connections between subnetworks.
The router table can take two forms: Dynamic or Static.