Dion Flashcards
Broadcast domain
Routers break up broadcast domains.
All ports on hubs and switches are in the same broadcast domain.
Collision domain
Switches and routers break up collision domains.
All ports on a hub are in the same collision domain.
RADIUS
A RADIUS (Remote Authentication Dial-In User Service) server is a central server that authenticates and authorizes remote users who access a network. RADIUS servers receive authentication requests from RADIUS clients, such as routers, firewalls, or VPNs. The RADIUS server verifies the user’s credentials and returns an authorization decision to the client.
RST
RST (reset) is a TCP flag that is used to terminate a connection when the sender senses that something has gone wrong with the connection.
FIN
FIN (finish) is a TCP flag that is used to request that a connection be terminated. This usually occurs at the end of a session and allows the system to release the system resources that were previously reserved for this connection.
SYN/ACK
SYN (synchronize) and ACK (acknowledge) are TCP flags used during the TCP three-way handshake at the beginning of a connection.
Sender: SYN
Receiver: SYN-ACK
Sender: ACK
Port security
Also known as MAC learning or Sticky MAC, this type of port security allows a switch to remember dynamically learned MAC addresses when the switch or interface is restarted or goes offline. The switch will only allow the computer with the original MAC address to connect via that switchport.
NetBIOS
NetBIOS, similar to DNS, allows primarily Windows machines to connect to each other by using a name rather than an IP address.
The “nbtstat -R” command will purge and reload the cached name table from the LMHOST file on their Windows workstation.
eDiscovery
A form of digital investigation that attempts to find evidence in email, business communications and other data that could be used in litigation or criminal proceedings.
DOCSIS modem
DOCSIS modems are cable modems that use coaxial cable with an F connector.
Analog modem
Analog modems convert digital computer signals to tones that can be carried over POTS (telephone) lines. These cables use RJ-11 connectors.
UTM
A Unified Threat Management appliance enforces a variety of security-related measures, combining the work of a firewall, malware scanner, and intrusion detection/prevention.
BGP
Border Gateway Protocol is a type of Exterior Gateway Protocol that allows Autonomous Systems on the internet to exchange routing information.
Geo-IP
Geo-IP/Geolocation identifies the country of origin of a host based on IP address.
802.1q
802.1q is a standard that allows traffic from several different VLANs to be transmitted across one trunk port. The traffic is then split up and appropriately sent to the correct VLANs once it reaches the other switch.
Trunking allows VLANs to be split up across separate physical switches.
RDP port number
3389
802.11g specs
2.4GHz and up to 54 Mbps
DHCP snooping
DHCP snooping are techniques used to improve the security of a DHCP infrastructure. This feature determines whether traffic sources are trusted or untrusted and is used to protect against rogue DHCP servers.
On Cisco networking devices, the “show config” command will display information including whether or not DHCP snooping is enabled.
Plenum-rated cable
Plenum-rated cables are designed to not burn as easily as normal cables. They are meant to be used in plenum spaces, which are used for air circulation.
PVC network cables can be hazardous because they create a noxious gas when burnt.
RPO
The recovery point objective (RPO) is the interval of time that might pass during a disruption before the quantity of data lost during that period exceeds the Business Continuity Plan’s maximum allowable threshold or tolerance.
WPS Attack
A WPS attack is a type of attack where a hacker exploits vulnerabilities in Wi-Fi Protected Setup (WPS) to gain access to a network. The most common method is a brute force attack, where the hacker uses a password generating tool to guess the PIN associated with the access point.
There are only 100 million possible PINs for WPS and and a design flaw exists that essentially lowers the number of possible PINs even further.
ipconfig /release
ipconfig /renew
These commands are used together in order to get a new dynamic IP address from the DHCP server.
Fusion splicer
Tool that joins two pieces of fiber optic cable together. This is used to repair breaks or simply make extra-long cables.
802.11a specs
5GHz at up to 54 Mbps.