The Internet Flashcards
How does the physical network constrain higher level protocols?
Higher-level protocols, such as TCP and HTTP, rely on the underlying network infrastructure in order to function. As such, they are bound by the limitations of that infrastructure, such as network bandwidth and latency.
What are protocols?
The protocols that support network functionality are essentially logical sets of rules that have been designed and engineered to be the way they are.
What is a network?
At the most basic level, it’s two devices connected in such a way that they can communicate or exchange data.
What is a local area network (LAN)?
A LAN is multiple computers and other devices connected via a network bridging device such as a hub or, more likely, a switch. The key thing to understand here is that the scope of communications is limited to devices that are connected (either wired or wirelessly) to the network switch or hub.
What are routers? What do they enable?
Routers enable communication between networks. Routers are network devices that can route network traffic to other networks. Within a Local Area Network, they effectively act as gateways into and out of the network.
How do we ensure that different hardware across the world can still communicate seamlessly?
With protocols. sets of rules that govern the exchange or transmission of data.
We have a wide number of protocols on the web, what are the two primary reasons for this?
- Different protocols were developed to address different aspects of network communication.
- Different protocols were developed to address the same aspect of network communication but differently for a specific use case.
What are some example of different aspects of network communication that different protocols deal with?
Some protocols deal with theflowandorderof all the messages in the conversation. Others govern syntactical rulesthat dictate thestructureof the message.
What is an example of two protocols that address the same aspect of network communication but differently for a specific use case:
TCP and UDP would be examples of two protocols that address the same fundamental aspect of communication, the transfer of messages between applications, but do so differently.
How does the OSI model divide its layers?
The OSI model divides the layers in terms of the functions that each layer provides (physical addressing, logical addressing and routing, encryption, compression, etc).
How does the TCP/IP model divid its layers?
The Internet Protocol Suite divides the layers in terms of the scope of communications within each layer (within a local network, between networks, etc).
In the realm of networking, what does data encapsulation generally refer to?
In networking, encapsulation essentially refers to hiding data from one layer by encapsulating it within a data unit of the layer below
What is a PDU?
Within our network models, a Protocol Data Unit (PDU) is an amount or block of data transferred over a network.
What is the PDU at the link/data link layer?
An ethernet frame
What is the PDU at the Internet/ network layer?
An IP packet
