Network Services and Servers Flashcards
What port does DHCP use on the server side? What is the other port used in DHCP?
The server side uses port UDP 67
The client side uses port UDP 68
Dynamic Host Control Protocol is used to assign/lease IP’s automatically to devices on the network from the DHCP Server Pool.
What is the Apple equivalent network service to SMB? And what port?
AFP - Apple Filing Protocol is the equivalent service to Microsoft’s Server Message Block - both these services allow you to remotely communicate with the network server. Port tcp/548.
What is a file server used for?
To centrally store and share files on a network.
E.g. photos can be stored to a centralised network server using SMB on top of NetBIOS - less (port TCP 445) and they can then be accessed from any device on the network.
On older versions of the Windows OS what ports were used for file sharing across a network and what protocol ran on these ports?
What is the newer version of this protocol and what port does it use?
UDP ports 137-139 were used for the NetBIOS (Network Service) protocol to allow communication (file sharing) across computers/devices on the same network (LAN).
In newer versions of Windows NetBIOS-less protocol is used for the same job on port 445 - this is more secure as it is not an “in the clear” connection. (encrypted data in transit)
What is a print server?
A print server is hardware or software that connects a printer to a LAN/network so that all connected network devices can utilise it.
What standard printing protocols do print servers use (to receive/send print jobs)?
SMB - Server Message Block (Windows), LPD - Line Printer Daemon (MacOS), IPP - Internet Printing Protocol (Cross OS protocol, supports all OSs/Operating Systems Plural)
What are Network Services?
A way of sharing communal tools: printers, centralised file sharing, mailboxes to all devices connect to a network (LAN). Most of these tools are accessed through a server that controls and hosts them.
Network Services improve/extend the capabilities/abilities of a network.
What is a redundant server and what is it used for?
A redundant server is a backup/clone server that can be activated if the primary/original server of that type fails. This eliminates any potential downtime.
Generally only vital servers have redundant servers/backup servers such as the Authentication server or Mail server.
What is the role of the Authentication Server in a network?
It stores the user credentials of the networks users and provides services that allow users to login to the network/authentication/verification of who they are.
What does UTM refer to in regards to network security?
Unified Threat Management (UTM) is a security approach where multiple security measures/features are rolled into one device or software.
For example a UTM Gateway may function as a firewall, spam filter, URL filter, VPN and Intrusion Detection System (IDS).
What is the job of a Load Balancer within a network configuration?
A load balancer distributes network load (traffic) across multiple servers to avoid overloading a single server, it also provides server fault/failure tolerance as if one server goes down the load balancer will re-route traffic through other servers to prevent network downtime.
It sits between the external internet connection and the servers in network topography/layout.
They are highly configurable and can prioritise traffic flow of certain websites and applications.
They can also have caches to respond instantly to internet requests with bits of information without involving any of the servers.
How does a load balancer provide fault tolerance/continues network function if a server goes down?
A load balancer can simply stop routing network traffic to the affected server if it goes down and reroute that traffic to other servers on the network thereby preventing any down time for clients on the network.
What is SCADA an example of?
Supervisory Control And Data Acquisition (SCADA) is a type of Industry Control System (ICS) used for electronically managing/automating closed loop equipment.
What is a DCS?
Distributed Control System (DCS) - is a computerized control system (type of ICS - Industry Control System) used to automate things like power grid management.
What does legacy mean/refer to in IT?
Something that has been superseded/improved upon but is still in use. Often are hard to replace.
E.g. 802.11a WiFi standard or PlayStation 2’s.
What is an EMBEDDED system?
A purpose built device with a dedicated function (specific task) with no access to the Operating System. Such as a door security system, calculator, ATM’s. Device system with generally a single task/purpose.
What are some IoT devices and what does IoT stand for?
Internet of Things (IoT) devices are things on the network that aren’t computers, network devices or server.
Some examples are smart appliances (smart over, fridge, lights, Amazon Echo device) or monitoring devices such as smart home thermostat.
Are Fit-Bits examples of an IoT device or an embedded system or both?
Both! They are purpose built devices with no access to their OS (embedded system/mini PC system) and are part of the Internet of Things - devices that can communicate on a network that aren’t PC’s or network devices.
What is the difference between the DNS and a DNS server (recursive resolver)?
The Domain Name System (or DNS records) is a database/phonebook of all the web domain names (such as google.com) and all of their corresponding IP addresses. It is arranged in a hierarchy:
1) Root Level - 13 root servers
2) Top Level Domains (TLD) - .com .org .net, etc
3) Second Level Domains
4) Sub-Domain
5) Host
The DNS Server (resolver) interacts with the DNS database to convert human readable domain names to machine-readable IP addresses and vice versa.
