relevant information) Questions With Complete Solutions
Content filtering:
Occurs when organizations use software that filters content,
such as emails, to prevent the accidental or malicious
transmission of unauthorized information.
Trusted vs. untrusted zones:
- Trusted zone (inside or private zone): Contains secure and
confidential traffic.
- Untrusted zone: May contain malicious hackers or security
threats; networks in this zone can allow improper access to
sensitive data.
Screened subnet:
A DMZ created by two physical firewalls.
Trouble Shooting Methodology:
1. Identify the problem
2. Establish a theory
3. Test the theory to determine the cause
4. Establish a plan of action
5. Implement the solution
6. Verify full system functionality
7. Document the findings, actions, and outcome
Divide and conquer:
,A program design strategy in which tasks are broken down into
subtasks, which are broken down into sub-subtasks, and so on,
until each piece is small enough to code comfortably.
Top-to-bottom/bottom-to-top
OSI model:
Refers to troubleshooting techniques that involve examining the
layers of the OSI model either from the top layer (application
layer) down to the bottom (physical layer) or vice versa.
Crosstalk:
A form of interference in which signals in one cable induce
electromagnetic interference (EMI) in an adjacent cable.
Interference:
Can come from various sources, including radio frequency (RF)
interference or coupling from other devices.
Attenuation:
Loss of power in a signal as it travels from the sending device to
the receiving device.
Transposer:
A device in or beyond the service area of a radio or television
station transmitter that rebroadcasts signals to receivers which
can't properly receive the signals of the transmitter because of a
physical obstruction.
Cyclic redundancy check
(CRC):
,An error-detecting code commonly used in digital networks and
storage devices to detect accidental changes to digital data.
Runts:
A frame that is smaller than the minimum frame size for IEEE-
802.3 standard frames.
Giants:
Any frame whose size exceeds the maximum transmission unit
(MTU).
Error disabled port status:
A port that is effectively shut down and no traffic is sent or
received on that port.
Administratively down port status:
The default status on an interface on routers.
Suspended port status:
The port configuration is not compatible with others in the same
etherchannel.
Power over Ethernet (PoE):
A wired networking standard that allows electrical power to be
sent along with data over standard Ethernet cables.
Power budget exceeded:
Devices may not function properly or could even shut down,
leading to network disruptions and critical services going
offline.
, Network loop:
A network has more than one active path carrying information
from the same source to the same destination, causing
information to loop and amplify itself.
Root bridge selection:
The switch with the lowest Bridge ID is chosen as root.
Port roles:
- Interface changes/assignments in switches running STP that
relates to how STP analyzes the LAN topology.
- Ex: Root Port, Designated Port.
TCP Port states:
1. Listening - waiting for connection
2. Established - connected to a remote computer
3. CLOSE_WAIT - remote side has closed connection
4. TIME_WAIT - local side closed connection; waiting for
delayed packets
Incorrect VLAN assignment:
- Symptoms: No connectivity between devices.
- Causes: Devices are configured to use different VLANs.
- Resolution: Reconfigure devices to use the same VLANs.
Default routes:
This is used when a route is not known or is infeasible.
Address pool exhaustion:
The depletion of the pool of unallocated IPv4 addresses.