Layer 4 Transport Layer

What layer is dealt with segments and datagrams?

Transport Layer (Layer 4)

Which two protocols are in Layer 4?

TCP and UDP

What are some reliability features within layer 4?

windowing and buffering

What is TCP?

a connection-oriented protocol that reliably transports data (segments) across a network.

What’s connection full protocol?

if a segment is lost or dropped then the protocol waits for a reply (an acknowledgement) and if there is no reply then it will resend that segment

what is a three way handshake?

When a server and a client set up a connection and communicate with eachother using SYN, SYN ACK, and ACK packets

What is a retransmission?

A process where a data segment is resent if an acknowledgment is not received, ensuring reliable communication.

What is UDP?

User Datagram Protocol is a conecctionless protocol meaning it doesnt have to wait for a connection

when you have a datagram or a segment which layer are you in?

layer 4

What protocol uses segemnts?

TCP

What protocol uses UDP?

User Datagram Protocol (UDP)

What makes UDP unreliable?

if a datagram is lost the sender will never know it happened

What is UDP good for?

audio and video streaming due to its lots of data and not needing a 3 way handshake and it can increase the performance of your network

what is windowing?

windowing is a type of flow control that allows the sender to either send more or less data before acknowledgement

What is buffering?

storing data temporarily in a memory if the bandwidth isn’t available

what are some layer 4 devices?

TCP, UDP, WAN accelerators, load balancers, firewalls

This layer checks to see if the data has arrived, puts things in the right order, and if anything is missing its resent

Layer 4