Hosts or end systems are devices that are being hooked up to the internet
End systems are connected together by a network of communication links and packet switches.
What is a transmission rate?
The rate at which data is transmitted over a network.
What is transmission rate measured in?
Bits per second (bps)
What are packets?
Units of data that are transmitted over a network.
The two most prominent packet switches in today's Internet are routers and link-layer switches.
The sequence of communication links and packet switches traversed by a packet from the sending end system to the receiving end system is known as a route or path through the network.
Packets can be compared to trucks.
Communication links can be compared to highways and roads.
Packet switches can be compared to intersections.
End systems can be compared to buildings.
End systems access the Internet through Internet Service Providers (ISPs)
End systems, packet switches, and other pieces of the Internet run protocols that control the sending and receiving of information within the Internet.
The Transmission Control Protocol (TCP) and the Internet Protocol(IP) are two of the most important protocols in the internet.
The IP protocol specifies the format of the packets that are sent and received among routers and end systems.
The Internet's principal protocols are collectively known as TCP/IP.
Internet standards are developed by the IETF.
The IETF documents are called RFCs (Request for Comments)
Internet applications are known as distributed applications, since they involve multiple end systems that exchange data with each other.
Internet applications run on end systems - they do not run in the packet switches in the network core.
Packet switches facilitate the exchange of data among end systems, they are not concerned with the application that is the source or sink of the data.