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Creating, managing, auditing, and disabling user accounts in an organization.  Security groups are added to accounts to provide access to corporate resources.  Access needs to be monitored and adjusted appropriately and removed promptly when someone leaves the organization.    

Using API's, scripts, and software to complete time consuming and monotonous tasks.  E.G. copying and pasting data from a ticketing system to an Excel sheet.      

 Bluetooth: used to connect two devices that are close to each other (~30 feet).   Common in wireless earbuds, wireless printers, etc.  Switches frequency hundreds  of times a second.  Devices have to be paired first 

NFC: connect device over very short distances (~4 inches).  Commonly used for  mobile payments, like Google Pay 

 (Dynamic Host Configuration Protocol) -- allows for automatically assigning and reserving IP addresses for connected devices.  Can provide default gateway, domain name, DNS servers and time servers info to devices.   It is like the road map of the network.  

In a small office / residential setting DHCP is often handled by the router.  In an enterprise setting DHCP runs on a server instance and device connect and renew IP leases.   

 (Domain Name System) - provides a naming system for resources on the internet or other IP networks.  Converts a common name to the IP address of the resource.   It consists of a set of distributed servers maintain the domain name hierarchy and IP address spaces for the internet.   

• The ‘phone book’ of the internet.  URLs and email addresses use DNS to find the IP to find / send to.   
• A, AAAA records, SMTP mail (MX), domain name aliases (CNAME) records 
• Hierarchical structure – ascends from right to left.   www.ITSupport.teckworm.com 
• .com is the ROOT 
• .teckworm is subdomain 
• .departments is subdomain of teckworm 
• Uses a lot of caching servers to speed up requests, devices have DNS cache as well to speed up searches.   

Convert plain-text into a form that is unreadable without a decryption key. Ensures confidentiality and protects data at rest and it transit in data transmissions.  You can employ symmetric (where both sender / receiver have the same key) or public keys (where the only the receiver has the key to decrypt).

 TLS (transport layer security): uses encryption to provide secure communications  for services like email, VoIP phones, HTTPS requests and more.  Runs in the Application layer.  

 A network device (or software) that monitors network traffic and allows or blocks inbound / outbound traffic on the network based on rules.  They evaluate packets against an number of criteria: 

• Direction: inbound or outbound 
• Source and destination (IP Address) 
• Port 
• Protocol 
• Applications (not all firewalls) 
• Action: Allow / Deny / Drop / Forward for further inspection  

Firewalls are used to protect corporate networks from the public internet and on individual devices as part of the overall security suite.  

• Individual devices: should have a software-based firewall.  Windows has the “Windows Firewall with Advanced Security” built in.   

 Open Systems Interconnection model) - rules / concepts that are used in data transmission and troubleshooting network issues. 

There are 7 layers: 

• Application – Displaying and receiving information from the user.  Mail services, Directory services, remote file shares, etc. 
• DHCP, DNS, FTP, HTTP, HTTPS, IMAP, LDAP, SSH, TLS\SSL 
• Presentation – AKA Translation layer.  Data is formatted for the application, JPEG, GIF, TLS, SSL.  Handles encryption, compression.  
• Session – establish, manage and terminate sessions between two devices.   
• Transport – provides services for upper application layers.  E.G ACK for successful data transmission and re-transmit missing data.  Adds Port numbers to headers so data is handled by the right process (e.g. a webserver, port 80) Data is in segments.  Protocols are TCP, UDP, Error detection and correction 
• Network – transmission of data across networks, with devices like routers and switches.  Data is in packets.  IP address is used for routing. 
• Protocols: ICMP, IPsec 
• Data Link -- (DLL) ensures data moves between the nodes without errors using devices like switches.  Data is in Frames.  DLL uses MAC addresses to route. 
• Protocols: ARP, PPP, MAC 
• Physical – Physical connection between the devices, cords, hubs, modems, etc.   Information is in bits.  Manages things like Bit rate control, Transmission mode (full duplex, half duplex etc)  
• E.G. sending an email:  User types message in Mail application --> data is formatted and encrypted --> session established and managed --> data is segmented --> segments are broken into packets and routed --> packets are broken into Frames and sent to next device --> data is transmitted in bits.  Then REVERSE process to see the message.   

 Uses psychological manipulation (fear, urgency, empathy) to get a person to share sensitive data or take an action, like opening a link. Phishing is the most common social engineering attack.  

 A type of attack in which perpetrators create fake webpages, email addresses, phone number and domains that look legitimate, but are not.  Victims then divulge private information.    

 An attack in which the victim’s files are encrypted and the attacker demands payment to decrypt the files.  The file name extensions change and the victim can’t open there own documents.    

 HDMI 

USB  

USB-C 

DVI 

VGA 

 Used to direct network traffic to the correct services, E.G. port 443 for HTTPS traffic.   

• Used in connection strings for access, like SQL queries (Object Connector in SSMS) 

VLAN

Trunk

Switch

MDF / IDF

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5G, 2.4G 

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Hypervisor

VMWare

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 Bluetooth: used to connect two devices that are close to each other (~30 feet).   Common in wireless earbuds, wireless printers, etc.  Switches frequency hundreds  of times a second.  Devices have to be paired first 

NFC: connect device over very short distances (~4 inches).  Commonly used for  mobile payments, like Google Pay 

More to come  

More to come

More to come

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