Mother Midterm...

Flashcard set for Network Architectures Midterm (CIS 3329)

WiFi 4

802.11n

WiFi 5

802.11ac

WiFi 6

82.11ax

BitTorrent 

A peer-to-peer file transfer protocol for sharing large amounts of data over the internet, in which each part of a file downloaded by a user is transferred to other users..

Botnet

A network of compromised devices that are secretly controlled by a single attacker to perform malicious activities.

Bandwidth

The maximum rate of data transfer over a connection.

Broadband

A high-speed internet connection that uses a wide range of frequencies, or several simultaneous frequencies, to transmit data.

Broadcast

A network communication method where data is sent to all devices on a local network.

Checksum

A mathematical value generated from data to verify its integrity.

Congestion Control

Prevents a sender from overwhelming the network capacity.

Flow Control

Prevents a sender from overwhelming a single reciever’s buffer.

Connection Oriented

Establishes a reliable, dedicated connection before data transfer, similar to sending a signed document via courier.

Connectionless

A communication model that sends data without a prior connection, like a postcard.

Content Distribution Network (CDN)

A geographically distributed network of servers that caches content closer to users to improve website performance and availability.

Dynamic Adaptive Streaming over HTTP (DASH)

An adaptive streaming protocol; allows for a video stream to switch between bit rates on the basis of network performance, in order to keep a video playing.

DNS Root Servers

Highest level servers in the DNS hierarchy; starting point for translating human-readable domain names into machine-readable IP addresses.

DNS TLD Server

Holds information for all domain names with a common extension, such as ".com" or ".org"

DNS Authoritative Name Server

Servers that hold the final, official records for a domain, providing the authoritative answer for an IP address when a DNS query is made

Authoritative name servers

When a recursive resolver can’t find an answer in its cache, it queries the _____ _____ _____ to get the correct IP address.

Bring Home

Placing fewer, larger server clusters in key locations, which simplifies management but can lead to higher user delay and lower throughput.

Enter Deep

Placing many smaller servers deep inside various access networks to be close to users, reducing delay but increasing management overhead.

Ethernet CSMA/CD

A protocol for managing access to a shared network cable in half-duplex Ethernet networks

Ethernet CSMA/CD

Works by having devices first "sense" the line to see if it's busy. If it's not, they send data; if two devices transmit at the same time and a "collision" occurs, they both stop, send a "jam" signal, and wait a random amount of time before trying again

FTP out-of-band

Uses two separate connections: one for control information (commands like login, list files, etc.) and a different one for the actual file data

In-band communication

Both control information and data travel over the same channel.

Frames

Encapsulates a network layer packet with a header and a trailer, which contain essential information for transmission, such as source and destination MAC addresses.

Non-persistent HTTP (HTTP/1.0)

A new TCP connection is established for every single request and response. 

Persistent HTTP (HTTP/1.1)

Reuses a single TCP connection to handle multiple requests and responses

HTTP/2

This protocol uses framing to address the HOL problem.

Head of Line (HOL)

A performance issue in networking and stream-based systems where a slow or lost packet at the beginning of a queue blocks all subsequent packets from being processed, even if they are ready

ICANN

The umbrella non-profit organization which assigns and ensures domain names and IP addresses are unique.

IMAP

This protocol allows manipulation of emails and creation of folders.

IPv4

(In DNS) Uses A records to map a domain name to a 32-bit address.

IPv6

(In DNS) Uses AAAA records to map a domain name to a 128-bit address.

Iterative Query

Sends a request to a DNS server, and the server provides the best answer it can, which might be a referral to another DNS server.

Recursive Query

Sends a request to a DNS server and expects a complete answer.

Internet2

A hybrid optical and packet network designed for research and education, distinct from the public internet.

Len Kleinrock

He developed the concept of packet switching,

Load balancing

The process of distributing network traffic across multiple servers to optimize resource usage, maximize throughput, and improve availability.

LAN Ring

A type of local area network where devices are connected in a closed loop, with each device linked to exactly two neighbors

STAR

a network architecture where all devices connect to a single central hub or switch

BUS

A type of network architecture where all devices are connected to a single, shared communication cable called a "____" or "backbone.

Virus

Self-replicating infection by receiving/executing object (e.g., e-mail attachment)

Worm

Self-replicating infection by passively receiving object that gets itself executed

Trojan

A malicious software program that disguises itself as a legitimate or useful application to gain unauthorized access to a computer or network

Malware

Software that is specifically designed to disrupt, damage, or gain unauthorized access to a computer system.

Manifest file

A structured configuration document that describes the network's components, services, and their required states

MIME

This protocol allows email to contain images, audio, video files as well as text.

Multiplexing in UDP

The process of gathering data from multiple application processes and combining it into single datagrams for the network layer, using a destination port number to identify which application process should receive the data on the receiving host

Demultiplexing in UDP

The process of directing incoming UDP datagrams to the correct application on a receiving host, using only the destination port number to identify the target socket

Multiplexing in TCP

The process of sending data from multiple application-layer connections over a single, shared TCP connection

Demultiplexing in TCP

The process at the receiving end that uses the information in a TCP segment's header to deliver the data to the correct application socket

Transmission delay

The time it takes for a device to send all the bits of a packet onto a network link (L/R)

Propagation delay

The time it takes for a single bit of a signal to travel from a sender to a receiver through a physical medium (distance/speed)

Queuing delay

The time a data packet spends waiting in a buffer in a network device, such as a router or switch, before it can be transmitted (1/(service rate - average arrival rate))

Packet switching

A network architecture that divides data into packets, which are then sent independently across a shared network and reassembled at the destination

Circuit switching

A network architecture that establishes a dedicated, physical path between two endpoints for the entire duration of a communication session

Peer-to-peer (P2P)

A decentralized network architecture where participants connect directly with each other to share resources, acting as both clients and servers.

Pharming

A type of attack that manipulates the DNS to redirect user traffic from a legit website to a fraudulent one without the users knowledge.

Poisoning

A type of attack that inserts false information into a DNS server’s cache, redirecting users from a legit website to a fraudulent one.

Ping

diagnostic utility that tests the reachability of a host on an IP network

Sequencing

The order of operations or data, and it can mean either the ordered delivery of data packets or the use of machine learning models that process sequential data

SMTP

The internet standard for sending and forwarding email messages from a client to a server and between mail servers

Socket

A software endpoint that acts as a doorway for communication between programs on a network

Three-way handshake

a TCP process that establishes a reliable connection between a client and server by exchanging three packets: SYN, SYN-ACK, and ACK

Throughput

The actual rate of data successfully transferred over a network in a given period, measured in bits per second (bps)

Traceroute

This program provides delay measurement from source to router along end-end Internet path towards destination.

TCP/IP Protocol stack

a four-layer network architecture that governs how data is transmitted across the internet and other networks.

TCP

Provides reliable, connection-oriented data delivery between applications.

UDP

A transport layer communication protocol that enables connectionless, fast, low-latency data transfer between network devices

Coax

A type of cable used to transmit data, the internet, video and voice communications

Fiber optic

Transmits data as pulses of light through glass or plastic strands

Unshielded twisted pair (UTP)

A copper cable with insulated wires twisted into pairs to reduce crosstalk and interference; forms the physical layer for ethernet

Simplex

Uses a unidirectional communication channel, where data flows only from the sender to the receiver

Half-duplex

A bidirectional communication mode where data can flow in both directions, but only one direction at a time

Full duplex

A network communication method that allows data to be sent and received simultaneously between two devices

Iterative query

Requests a website name or URL by providing references to other DNS servers that might have the answer.

Recursive query

One DNS server communicates with several other DNS servers to hunt down an IP address and return it to the client.

“maintain the state” (stateful architecture)

The system actively remembers data from previous interactions, transactions, or sessions. This allows the network to process future requests with full context of a client's past activity.

Stateless architecture

Treats every request as an independent, new interaction with no memory of prior ones.

The application layer uses SMTP to send the message from the client to the mail server, and TCP is used at the transport layer to establish a reliable connection for data transfer

Diagram and identify application and transport layer protocols in sending an email.

Cookies and a back end database

How do websites keep track of the site user traffic

Ok

(This is just a flashcard to read, just answer “Ok”) Cookies and the website backend work because: when a user first visits a website, the server may generate a unique identifier for that user and store it in its backend database, associated with any relevant user data (like preferences or session information, this is the cookie), then the website backend database stores the actual user data associated with these unique identifiers so that it can be retrieved the next time the user visits the website.