2.4 Network Services

Question 1

DNS

Answer 1

Domain Name System
- convert domain names to IP addresses and vice versa
- businesses may have many different DNS servers that split the work load

Question 2

DHCP

Answer 2

Dynamic Host Configuration Protocol
- automatically assign IP address and configure devices on IP networks
- available on most routers
- multiple DHCP servers provide redundancy should one become available

Question 3

Fileshare Server

Answer 3

• centralized storage of documents, spreadsheets, pictures, etc.
• any connected device has access
• Windows communicates with SMB
• macOS communicates with AFP

Question 4

Print Servers

Answer 4

• connect printer to the network
• may require software in a connected computer
• all other devices will send print jobs to this computer
• others may have network adapter and software built into printer -> direct connection to ethernet or wireless network
• printing protocols: SMB, IPP, LPD

Question 5

Mail Servers

Answer 5

• sends and receives mail
• usually managed by ISP, cloud-based service, or the enterprise IT department
• very important: 24/7 support

Question 6

Syslog

Answer 6

• standard for message logging
• usually a central logging receiver
• requires a lot of disk space

Question 7

Web Server

Answer 7

• responds to browser requests
• HTTP/HTTPS
• web pages are stored on the server
• static pages or built dynamically in real-time

Question 8

Authentication, Authorization, & Accounting (AAA)

Answer 8

• security framework for controlling and tracking user access within a network
  Authentication:
• identifying the user
• username and password
• biometrics or access badge
  Authorization:
• user must be authorized to perform certain tasks
  Accounting:
• measuring how many resources the user consumes
• time and data used
  Very important: redundant servers are common

Question 9

Spam Gateways

Answer 9

• stops spam before it reaches the user
• can be stored in the cloud
• once the mail is scanned, it can be sent to the internal network and stored in the mail server

Question 10

Unified Threat Management (UTM)

Answer 10

• aka Next-Generation Firewall
• multiple security features or services are combined into a single device or service in the network:
• spam filter, URL filter, malware inspection

Question 11

Load Balancers

Answer 11

• distributes traffic to multiple servers
• efficient
• large-scale implementations
• TCP offload and SSL offload

Question 12

Proxy Server

Answer 12

• additional security
• client makes request to proxy -> proxy sends request to third-party server
• proxy examines the response for any malicious threats -> sends response to client

Question 13

SCADA/ICS

Answer 13

Supervisory Control and Data Acquisition System/ Industrial Control System
- management of industrial processes
- real-time data collection and process control

Question 14

Legacy/ embedded systems

Answer 14

Legacy systems:
- outdated systems that are still in use
Embedded systems:
- devices or softwares that has a specific function within a larger system
ex. Alarm system, time card system

Question 15

IoT (Internet of Things) devices

Answer 15

• nonstandard computing hardware that connect can connect to wireless networks
  Ex. Sensors, smart devices, smart doorbell, appliances