Network Services Flashcards
DNS server
stands for
what does it do
how many
Domain name system
- converts names to IP address
- will prob have many dns servers within the same data center
DHCP server
Dynamic host configuration protocol
assigns IP addresses to devices
These are file servers, what do they stand for
SMB windows
AFP mac
Server message block
apple filing protocol
printer server
software running on computer
may also have hardware card allows the printer to connect to
an Ethernet connection
What are three protocols you can use for printers
SMB
IPP
LPD
SMB-server message block
IPP internet printing protocol
LDP line printer daemon
Syslog
SIEM:used to collect log files
a centralized database to view log information
Security information and event manager
What two protocols are used for web servers
They are built with what coding langL
HTTP
HTTPS
HTML
HTML5
Authentication server
a specialized server in a computer network that is responsible for verifying the identity of users or devices trying to access network resources. Its primary function is to authenticate and authorize users based on their provided credentials, such as usernames and passwords, digital certificates, or other authentication methods.
What is a mail gateway
a network device or software application that acts as an intermediary for the transmission of email messages
crucial role in the routing, filtering, and delivery of email messages
Next-generation firewall, Unified Threat
an advanced network security device that combines traditional firewall capabilities with additional security features
.
Load balancers
a network device, software application, or service that efficiently distributes incoming network traffic or workload across multiple servers or resources* 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
Load balancer features
- Configurable load - Manage across servers
- TCP offload - Protocol overhead
- SSL offload - Encryption/Decryption
- Caching - Fast response
- Prioritization - QoS
- Content switching - Application-centric balancing
Proxy servers
useful features 4
- Proxy servers can hide a user’s IP address
-Proxies can be configured to filter web content,
-Proxies can cache frequently accessed web content locally
-Load Balancing and Traffic Distribution:
SCADA/ICS
hint:industrial
- Supervisory Control and Data Acquisition System
– Large-scale, multi-site Industrial Control Systems (ICS)crucial role in monitoring, controlling, and managing various processes and equipment in industries such as manufacturing, energy, water supply, transportation, and more.
Legacy devices what are they
– Another expression for “really old”
– May also be “really important”
– Learning old things can be just as important as
learning the new things
embedded systems at a data center what are they
– Purpose-built device
– Not usual to have direct access to
the operating system
– Alarm system, door security, time card system
ioT devices
Internet of things devices embedded with sensors, software, and network connectivity, allowing them to collect and exchange data with other devices and systems over the internethousehold appliances, vehicles, industrial machinery, medical devices,
Bits: Each IPv4 address is made up of ____bits in total.
Bytes: Since each byte consists of ___bits, to find the number of bytes, you divide the total number of bits by ___:
___ bits / ____bits/byte = ____ bytes
So, an IPv4 address consists of 4 bytes.
Maximum Decimal Value for Each Byte: Since each byte in an IPv4 address is composed of 8 bits, you can calculate the maximum decimal value for each byte by taking 2^8 (2 raised to the power of 8):
2^8 = 256
Therefore, the maximum decimal value for each byte in an IPv4 address is 256. However, IPv4 addresses use values ranging from 0 to 255, not 1 to 256, so valid decimal values for each byte in an IPv4 address range from 0 to 255.
32 bits
8 bits
8
32bits
8bits
4 bytes
255
IPv6
___bits
___bytes
they tend to be assigned with a ___ bit subnet mask meaning
128 bits in length, which is four times the length of IPv4 addresses (32 bits)
16 bytes because each byte consists of 8 bits.first
first 64 bits are the network address (subnet mask)
the last 64 bits are the host address
what is a subnet masks
a 32-bit number used in Internet Protocol (IP) addressing to divide an IP address into network and host portions. It’s a fundamental concept in IP networking and plays a crucial role in determining how IP addresses are assigned to devices on a network. The subnet mask essentially tells devices which part of an IP address identifies the network and which part identifies the specific device within that network.
what is a default gate way
The IP of a router if you need to communicate outside of your network
The bootstrap protocol
what month/year was it established and what is it
used to assign IP addresses before dynamic host configuration protocol was createdoct 1993
Dynamic host configuration protocol
what year
used to assign IP addresses
1997
what is theDynamic host configuration protocol process 4 steps
DORA
* Step 1: Discover
- Client to DHCP Server
– Find all of the available DHCP Servers
* Step 2: Offer
- DHCP Server to client
– Send some IP address options to the client
* Step 3: Request
- Client to DHCP Server
– Client chooses an offer and makes a formal request
* Step 4: Acknowledgment
- DHCP Server to client
– DHCP server sends an acknowledgment to the client
what are two things you can do if you want a device to always have the same IP address
- you can disable DHCP and configure the ip address information manually
- configure an IP reservation on the DHCP server
What is a APIPA address
Automatic Private IP Addressing
feature in Microsoft Windows operating systems that allows a computer to automatically assign itself a private IP address when it is unable to obtain an IP address from a DHCP (Dynamic Host Configuration Protocol) server. APIPA is designed to provide a basic level of network connectivity when no DHCP server is available, ensuring that the computer can still communicate with other devices on the local network.
169.254.0.1 to 169.254.255.254, with a subnet mask of 255.255.0.0.
– Uses ARP to confirm the address isn’t currently in use
how many root server clusters or DNS
13 root server clusters
over 1,000 actual servers
Address records (A) (AAAA)
used to map domain names to IP addresses.
– This is the most popular query
- A records are for IPv4 addresses
– Modify the A record to change the host name to IP address resolution
- AAAA records are for IPv6 addresses
– The same DNS server, different records
what are resource records that are used on a dns server
- data entries used in DNS (Domain Name System)
-DNS servers use these records to resolve domain names to their corresponding IP addresses or to provide other important information related to domain name
-over 30 records types
Mail exchanger record (MX)
MX records specify the mail servers responsible for receiving email messages on behalf of a domain. They include the mail server’s hostname and a priority value for routing email.
TXT (Text) Record:
SPF
TXT (Text) record is a type of DNS (Domain Name System) resource record used to store plain text information associated with a domain name.
authentication purposes like SPF (Sender Policy Framework) records used in email authentication.
(SPF)
Sender policy frame work
A mechanism that tell receiving email servers what servers they are allowed
for this domain
– Prevent mail spoofing:email that appears to come from a different source than it actually does.
Domain Keys Identified Mail (DKIM)
- authentication method and cryptographic technique used to verify the authenticity of email messages–
-email server sends an outgoing message on behalf of a domain, it adds a DKIM signature to the message’s header.
-This public key is used by receiving email servers to verify the DKIM signature. - The public key is in the DKIM TXT record
DMARC
DMARC
* Domain-based Message Authentication, Reporting,
and Conformance (DMARC)
– Prevent unauthorized email use (spoofing)
– An extension of SPF and DKIM
* You decide what external email servers should do with
emails that don’t validate through SPF or DKIM
– That policy is written into a DMARC TXT record
– Accept all, send to spam, or reject the email
– Compliance reports can be sent to the email administrato
Unified Threat Management (UTM) / Web Security Gateway:
Unified Threat Management (UTM) devices and Web Security Gateways are all-in-one security appliances that integrate multiple security features into a single platform. UTM devices typically include firewall, antivirus, anti-spam, URL filtering, and content filtering capabilities.
