KC4

What does DHCP stand for and what is its purpose?

Dynamic Host Configuration Protocol, and it is used to connect devices to a network.

What is the function of ARP in networking?

Address Resolution Protocol, and it is used to find the next hop IP address in a network.

What is DNS and what does it do?

Domain Name System, and it resolves a domain name to an IP address.

What does NAT do?

Network Address Translation, and it keeps your private IP address off the public internet.

What does HTTP do?

Requesting and sending webpage files (html, css)

What is packet switching?

Breaks a message into packets and sends them independently over a network.

What is circuit switching?

The old telephone operator way of connecting to someone. Dedicated connection, expensive, consistent bandwidth, if one part breaks everything breaks.

What is a significant advantage of packet switching?

More efficient and provides greater redundancy in data transmission.

What is a packet?

The minimal unit of network information

What is a header?

The addressing information for a packet

What does each layer have to track its data?

A header

What is a drawback of packet switching?

Latency, where some packets may experience delays.

What is the job of the datalink layer?

Manage access to physical media. Handles packet delivery between physically connected devices. Uses MAC addresses.

What is cloud computing?

The on-demand delivery of IT resources with a pay-as-you-go pricing model.

What is Amazon EC2?

Amazon Elastic Compute Cloud, which provides flexible, cost-effective computing resources.

What is an advantage of using a hypervisor?

Keeps instances secured and separate from one another.

What is Elastic Load Balancing?

An application that distributes incoming application traffic across multiple instances.

What is the main difference between circuit switching and packet switching?

Circuit switching establishes a dedicated connection, while packet switching transmits data in packets over shared networks.

What are Security Groups in AWS?

Virtual firewalls that control inbound and outbound traffic for AWS EC2 instances.

What is the role of AWS Route 53?

DNS service that translates website names into IP addresses.

What is the purpose of Amazon CloudFront?

Content delivery network (CDN) that delivers edge content to users based on their location.

Define horizontal scaling in cloud computing.

Adds more EC2 instances with smaller resources to distribute load among multiple nodes.

What is the purpose of Auto Scaling in AWS?

Automatically adjusts the number of EC2 instances based on demand.

What is the difference between stateful and stateless security?

Stateful checks if packets are on the approved list and remembers, while stateless checks every packet independently.

What does AWS Lambda do?

Runs code for under 15 minutes and scales functions based on application demand.

What does VPC stand for and what is its function?

Virtual Private Cloud, used to launch AWS resources in a virtual network you define.

What is a benefit of using Reserved Instances in AWS?

Provide a significant discount for predictable usage over a longer term.

What is the difference between AWS EC2 and AWS Lambda?

EC2 provides virtual machines for various applications, while Lambda allows for serverless computing without managing servers.

What are Availability Zones?

Isolated data centers within a region, providing high availability and redundancy.

What are Edge Locations in AWS?

Sites that Amazon CloudFront uses to deliver content to users with low latency.

What is a General EC2?

Good balance of resources

What is a compute optimized EC2 instance?

Compute intensive tasks. Uses high performance processors

What is a memory optimized EC2 instance?

Fast delivery for workloads that process large datasets in memory.

What is an accelerated computing EC2 instance?

Hardware accelerators to perform some functions more efficiently than is possible in software running on CPUs

What is a storage optimized EC2 instance?

For workloads that require high sequential read and write access to large datasets on local storage

What is on demand pricing?

Per hour or per second paying

What is the savings plan?

One or three year term. Saves a lot of money because you sign up for a set amount of time.

What is the reserved instance payment plan?

For use with predictable traffic use. Gets a big discount.

What is a spot instance?

Amazon can reclaim the instance at any time. For instances that can withstand being disconnected temporarily.

What is a dedicated host payment plan?

Physical servers with EC2 instance capacity that is fully dedicated to one company’s use.

What is a monolithic application?

Tightly coupled architecture. If one application fails, they all fail.

What is loosely coupled architecture?

Microservices. Has a buffer between applications and allows for messages to be saved if one application fails.

What is amazon SQS?

Send, store and receive messages between software components without losing messages or requiring other services to be available.

What is amazon ECS?

Supports docker containers and can launch/stop Docker applications.

What is AWS EKS?

Run Kubernetes on AWS.

What is Kubernetes?

Open source software that enables you to deploy and manage containerized applications at scale.

What is AWS Fargate?

Serverless compute engine for containers. Works with both ECS and EKS. No provision or server management.

What is an ELB?

Regional construct. Runs across all availability zones.

What kind of regional service is AWS?

Regionally scoped service

What is IMAP?

Used to download emails from a server to a client.

What is POP3?

Used to download emails from a server to a client (older and used to delete emails from the server)

What is SMTP?

Used to send emails between email servers (required still!)

What is MX?

A special DNS record for email servers.

What is port 80?

HTTP

What is port 22 for?

SSH

What is port 443 used for?

HTTPS

What is a registered port?

Used for a common service.

What is a dynamic port?

Used for a source port. You make a request and they know where to respond.

What is ping?

Uses IMCP to test the reachability of network devices, check for packet loss and diagnose network issues.

What is traceroute?

Uses IMCP to trace the path a packet takes from a source destination.

What is RDP?

Port 3389. Used to graphically connect and control the other computer.

What is SFTP?

Port 22. Built over SSH and used to transfer files.

What is the elastic beanstalk?

Helps you to reach the cloud. Platform as a service.

What is the c in CIA?

Confidentiality

What is the I in CIA?

Integrity.

What is the A in CIA?

Availability.

What is a Network Access Control List?

Controls what is allowed onto a network or subnet.