Focus Questions for Exam Flashcards
In the OSI model, the layer 4 TCP PDU is known as:
A segment
In the OSI model, the layer 4 UDP PDU is called:
A datagram
What is another name for star topology?
Hub and spoke
What is at the end of the main network cable in a bus topology and why?
A terminator, to prevent collisions from signal bounce
What is SD-WAN and what are its benefits?
Software-defined wide area network. It’s basically smart WAN. The software intelligently optimizes and routes data between offices and the internet.
What’s it called when two or more network topologies are combined?
Hybrid topology
What’s the difference between MPLS and SD-WAN?
MPLS is to trains as SD-WAN is to buses. MPLS requires specialized equipment, costs more, and is difficult to alter. SD-WAN doesn’t require specialized hardware, is cost effective, and more adaptable. Both offer increased data transport efficiency.
Port 389
LDAP / Authentication
Port 3389
RDP / Remote Desktop
Why and how is Netflow useful?
It gathers information on a network and can summarize the most common networking activity. Information is gathered by devices equipped with netflow probes. AKA “top network conversations”
Who developed the Netflow protocol?
Cisco
How would you prevent multicast flooding
By enabling IGMP snooping. It ensures that multicast traffic is only sent to devices that requested it.
What’s the difference between MDI and MDI-X?
MDI uses pins 1 and 2 for transmit and pins 3 and 6 for receive. MDI-X uses pins 1 and 2 for receive and pins 3 and 6 for transmit.
What are the pin colors for a T-568A?
striped green, green, striped orange, blue, striped blue, orange, striped brown, brown
What are the pin colors for a T568B?
striped orange, orange, striped green, blue, striped blue, green, striped brown, brown
What is an evil twin and what’s its purpose?
A fake or rogue wi-fi access point. used to steal sensitive information
What is FHRP and why is it important?
First Hop Redundancy Protocol. It’s essentially a backup router in case the primary one fails. It provides “high availability”
What does MTTR stand for?
Mean Time To Repair
What does MTBF stand for?
Mean Time Between Failures
What is RPO?
Recovery Point Objective. It’s the maximum amount of data loss allowed, measured in time, before it negatively impacts the business.
What is RTO?
Recovery Time Objective. It’s the maximum amount of time allowed to recover from a failure before the business is negatively impacted.
What is Clientless VPN?
A VPN that doesn’t require a client software to be installed. Often accessed via web browser over SSL or TLS.
What is ethernet flow control?
A protocol that tells transmitting device to pause transmission with pause frames when receiving device is overwhelmed at current data rate
What is POTS? What connector is used for it, and how many of the copper pins are used?
Plain Old Telephone Service. RJ11 connectors are used, and usually 2 or 4 pins are used.
What’s the difference between east-west traffic and north-south traffic?
East-west is traffic within the data center’s local network.
North-south is traffic between the data center and internet/clients
Why is BSSID useful, and how is it different from a regular SSID? Also, what does it stand for?
BSSID stands for Basic Service Set Identifier. It’s the hardware identifier for the wireless access point, so if you have multiple SSIDs with the same name, you can identify specific access points with it.
What is a PDU, and what do they describe?
Stands for Protocol Data Unit. It describes the type of data unit based on a specific layer of the OSI model.
What is the PDU of the Session, Presentation, and Application layers?
Data
What is the PDU of the Physical layer?
Bits
What is the PDU of the Data Link layer?
Frame
What is the PDU of the Network layer?
Packet
Besides Protocol Data Unit, what else does PDU stand for?
Power Distribution Unit
What are two terms that STP stand for and what are they?
Spanning Tree Protocol and Shielded Twisted Pair. Spanning Tree Protocol prevents data at Layer 2 from looping indefinitely. Shielded Twisted Pair are copper wires in ethernet cables that are covered in foil to prevent electromagnetic interference.
What is the difference between SMF and MMF, and what do they stand for?
Single-Mode Fiber and Multi-Mode Fiber. Single-Mode has a smaller core diameter, can go longer distances and has high bandwidth. Multi-Mode has a thicker core diameter, can handle multiple light signals, and is good for shorter distances.