2.4 - Network Services Flashcards
1
Q
DNS server
A
- Domain Name System
– Convert names to IP addresses
– And vice versa - Distributed naming system
– The load is balanced across many different servers - Usually managed by the ISP or IT department
– A critical resource
2
Q
DHCP server
A
- Dynamic Host Configuration Protocol
– Automatic IP address configuration - Very common service
– Available on most home routers - Enterprise DHCP will be redundant
– Usually running on central servers
3
Q
File server
A
- Centralized storage of documents,spreadsheets,
videos, pictures, and any other files
– A fileshare - Standard system of file management
– SMB (Server Message Block),
Apple Filing Protocol (AFP), etc. - The front-end hides the protocol
– Copy, delete, rename, etc.
4
Q
Print server
A
- Connect a printer to the network
– Provide printing services for all network devices - May be software in a computer
– Computer is connected to the printer - May be built-in to the printer
– Network adapter and software - Uses standard printing protocols
– SMB (Server Message Block), IPP (Internet
Printing Protocol), LPD (Line Printer Daemon)
5
Q
Mail server
A
- Store your incoming mail
– Send your outgoing mail - Usually managed by the ISP or the IT department
– A complex set of requirements - Usually one of the most important services
– 24 x 7 support
6
Q
Syslog
A
- Standard for message logging
– Diverse systems, consolidated log - Usually a central logging receiver
– Integrated into the SIEM - You’re going to need a lot of disk space
– No, more. More than that.
7
Q
Web server
A
- Respond to browser requests
– Using standard web browsing protocols - HTTP/HTTPS
– Pages are built with HTML, HTML5 - Web pages are stored on the server
– Downloaded to the browser
– Static pages or built dynamically in real-time
8
Q
Authentication server
A
- Login authentication to resources
– Centralized management - Almost always an enterprise service
– Not required on a home network - Usually a set of redundant servers
– Always available
– Extremely important service
9
Q
Spam
A
- Unsolicited messages
– Email, forums, etc. - Various content
– Commercial advertising
– Non-commercial proselytizing
– Phishing attempts - Significant technology issue
– Security concerns, resource utilization,
storage costs, managing the spam
10
Q
Spam gateways
A
- Unsolicited email
– Stop it at the gateway before it reaches the user
– On-site or cloud-based
11
Q
All-in-one security appliance
A
- Next-generation firewall, Unified Threat
Management (UTM) / Web security gateway - URL filter / Content inspection
- Malware inspection
- Spam filter
- CSU/DSU
- Router, Switch
- Firewall
- IDS/IPS
- Bandwidth shaper
- VPN endpoint
12
Q
Load balancers
A
- Distribute the load
– Multiple servers
– Invisible to the end-user - Large-scale implementations
– Web server farms, database farms - Fault tolerance
– Server outages have no effect - Very fast convergence
13
Q
Load balancer features
A
- Configurable load - Manage across servers
- TCP offload - Protocol overhead
- SSL offload - Encryption/Decryption
- Caching - Fast response
- Prioritization - QoS
- Content switching - Application-centric balancing
14
Q
Proxy server
A
- An intermediate server
– Client makes the request to the proxy
– The proxy performs the actual request
– The proxy provides results back to the client - Useful features
– Access control, caching, URL filtering, content scanning
15
Q
SCADA / ICS
A
- Supervisory Control and Data Acquisition System
– Large-scale, multi-site Industrial Control Systems (ICS) - PC manages equipment
– Power generation, refining,
manufacturing equipment
– Facilities, industrial, energy, logistics - Distributed control systems
– Real-time information
– System control
– Requires extensive segmentation
– No access from the outside
