1The primary use of NAT is to conserve what?
public IPv4 addresses
2This NAT term refers to the set of networks that are subject to translation
inside network
3This NAT term refers to all networks other than the ones being translated
outside network
4NAT terminology is always applied from the perspective of which device?
the device with the translated address
5The address of the device which is being translated by NAT
inside address
6The address of the destination device in NAT terminology
outside address
7Any address that appears on the inside portion of the network
local address
8Any address that appears on the outside portion of the network
global address
9What does PAT stand for?
Port Address Translation
10Another name for Port Address Translation (PAT)
NAT overload
11Why does NAT increase forwarding delays?
translation of each IPv4 address within the packet headers takes time
12Why does NAT complicate the use of tunneling protocols like IPsec?
it modifies header values, causing integrity checks to fail
13A network required to connect beyond the boundary of the LAN
Wide Area Network (WAN)
14The document that defines the private IP address spaces used in networking
RFC1918
15In NAT, the actual private IP address assigned to a device on the internal network
inside local address
16In NAT, the public IP address that represents one or more internal IP addresses to the outside world
inside global address
17In NAT, the IP address of an external host as it appears to the internal network
outside local address
18In NAT, the actual public IP address assigned to a host on the external network
outside global address
19A one-to-one mapping between a local internal IP address and a global external IP address
static NAT
20A NAT configuration that maps unregistered IP addresses to a registered IP address from a pool of available public addresses
dynamic NAT
21Port Address Translation, a feature that maps multiple private IP addresses to a single public IP address using different port numbers
PAT
22The Cisco command used to configure a one-to-one static NAT mapping
ip nat inside source static
23The Cisco command used to view active, current NAT translations in the router's memory
show ip nat translations
24The Cisco command used to view NAT statistics, such as total active translations and hits/misses
show ip nat statistics
25The Cisco interface configuration command that designates an interface as connected to the external network for NAT
ip nat outside
26The Cisco interface configuration command that designates an interface as connected to the internal network for NAT
ip nat inside
27The Cisco command used to create a range of public IP addresses for dynamic NAT allocation
ip nat pool
28The Cisco command used to remove all dynamic NAT entries from the translation table
clear ip nat translation *
29The keyword used in a Cisco PAT configuration to allow multiple inside devices to share a single outside IP address
Overload
30A translation technology that allows communication between IPv6-only and IPv4-only networks
NAT 64
31What are the common components of network documentation?
Physical and logical network topologies, network device documentation, and network performance baseline documentation.
32What are the seven steps of the structured troubleshooting process?
Define the problem, Gather information, Analyze information, Eliminate possible causes, Propose hypothesis, Test hypothesis, and Solve the problem.
33What are examples of common troubleshooting tools?
NMS tools, knowledge bases, baselining tools, protocol analyzer, digital multimeters, cable testers, cable analyzers, portable network analyzers, Cisco Prime NAM, and syslog servers.
34Which OSI layer problems cause complete failures and suboptimal conditions?
Physical layer
35What typical errors cause Data link layer problems?
Encapsulation errors, address mapping errors, framing errors, and STP failures or loops.
36Which OSI layer problems include IPv4, IPv6, and routing protocols like EIGRP and OSPF?
Network layer
37Misconfigured NAT or ACLs are problems associated with which OSI layer?
Transport layer
38Unreachable or unusable resources are symptoms of problems at which OSI layer?
Application layer
39Which troubleshooting method starts at the physical layer and works its way up?
Bottom-up troubleshooting method
40What technology uses networks to connect large numbers of computers anywhere to reduce operational costs?
Cloud computing
41What are the three main cloud computing services defined by NIST?
Software as a Service (SaaS), Platform as a Service (PaaS), and Infrastructure as a Service (IaaS).
42What are the four types of clouds?
Public, private, hybrid, and community.
43What is the foundation of cloud computing that separates the OS from the hardware?
Virtualization
44What type of hypervisor is installed directly on the server or networking hardware?
Type 1 hypervisor (bare metal)
45What type of hypervisor runs as software on top of an OS to create VM instances?
Type 2 hypervisor
46What is required to manage a Type 1 hypervisor?
A management console
47What type of data center traffic flows between virtual servers?
East-West traffic
48What type of data center traffic flows between the distribution and core layers toward offsite locations?
North-South traffic
49What are the two major network architectures developed to support network virtualization?
Software-Defined Networking (SDN) and Cisco Application Centric Infrastructure (ACI).
50What plane is regarded as the brains of a network device?
Control plane
51What is the core concept of Software-Defined Networking (SDN)?
The separation of the control plane and data plane, moving the control plane to a centralized controller.
52Which plane is typically the switch fabric used to forward traffic flows?
Data plane (forwarding plane)
53Which plane is responsible for managing a device through its connection to the network?
Management plane
54What hardware solution integrates cloud computing and data center management using a two-tier spine-leaf topology?
Cisco Application Centric Infrastructure (ACI)
55What are the three core components of the ACI architecture?
Application Network Profile (ANP), Application Policy Infrastructure Controller (APIC), and Cisco Nexus 9000 Series switches.
56What are the three types of SDN?
Device-based SDN, Controller-based SDN, and Policy-based SDN.
57Which type of SDN operates at a higher level of abstraction and is the most robust?
Policy-based SDN
58What APIC-EM tool helps administrators visualize traffic flows and discover conflicting ACL entries?
APIC-EM Path Trace tool
59What is any process that is self-driven, reducing the need for human intervention?
Automation
60What do smart devices require to "think" and act based on outside information?
Network automation tools
61What are structured ways to store and interchange data called?
Data formats
62What are three common data formats used in network automation?
JavaScript Object Notation (JSON), eXtensible Markup Language (XML), and YAML Ain’t Markup Language (YAML).
63What is a set of rules describing how one application can interact with another?
Application Programming Interface (API)
64What are the three classifications of APIs based on who can use them?
Open/Public APIs, Internal/Private APIs, and Partner APIs.
65What are the four main types of web service APIs?
SOAP, REST, XML-RPC, and JSON-RPC.
66Which API architecture defines functions using HTTP protocols like GET and POST?
Representational State Transfer (REST)
67What are the RESTful operations represented by the acronym CRUD?
Create, Read, Update, and Delete
68What HTTP methods correspond to the RESTful CRUD operations?
POST (Create), GET (Read), PUT/PATCH (Update), and DELETE (Delete).
69What identifier is used for web resources and services like RESTful APIs?
Uniform Resource Identifier (URI)
70What format is typically used for the payload response in a RESTful Web service?
JSON
71What are the different parts of an API request?
API server, Resources, and Query.
72What is the arranging of automated tasks that results in a coordinated process or workflow?
Orchestration
73What approach takes a software-centric, fully automated approach to designing and operating networks?
Intent-Based Networking (IBN)
74What are the three essential functions of Cisco IBN?
Translation, Activation, and Assurance.
75In IBN, what term describes the logical topology used to virtually connect devices?
Overlay Network (Fabric)
76In IBN, what is the physical topology that includes all hardware required to meet business objectives?
Underlay Network
77What is the single interface command center for provisioning and configuring network devices in Cisco DNA?
Cisco DNA Center
78What framework unifies wired and wireless access and is built on a hierarchical, scalable, and resilient infrastructure?
Cisco Borderless Network
79What are the three critical layers within the three-tier hierarchical design model?
Access, distribution, and core layers
80What technology bundles multiple links to increase bandwidth and provide load balancing?
EtherChannel
81What are the three common form factors for switches?
Fixed configuration, modular configuration, and stackable
82What part of the destination IP address do routers use to route packets to the proper destination?
The network portion (prefix)
83A Wide Area Network service provided by a telecommunications provider over shared public infrastructure
public WAN
84A Wide Area Network dedicated exclusively to a single customer, offering guaranteed bandwidth and security
private WAN
85A WAN design utilizing only one service provider, lacking redundancy if the provider fails
single-carrier WAN connection
86A WAN design utilizing two different service providers to ensure high availability and redundancy
dual-carrier WAN connection
87Modern WAN Layer 1 optical fiber protocol standards
SDH, SONET, and DWDM
88A global standard outside North America for synchronous data transmission over optical media
Synchronous Digital Hierarchy (SDH)
89The North American standard for synchronous data transmission over optical fiber
Synchronous Optical Networking (SONET)
90A technology that multiplies data capacity on a single optical fiber by sending multiple light wavelengths simultaneously
Dense Wavelength Division Multiplexing (DWDM)
91The customer's endpoint device that connects to the WAN, such as a router
data terminal equipment (DTE)
92The service provider's equipment that provides clocking and the interface to the WAN link
date communication equipment (DCE)
93Devices and wiring located on the subscriber's premises and connected to a telecommunication channel
customer premises equipment (CPE)
94The physical location where a customer connects to the service provider's network
point-of-presence
95The specific physical point where the service provider's network ends and the customer's private network begins
demarcation point
96The physical link or circuit connecting the customer premises to the service provider's edge
local loop
97A common industry term for the local loop, representing the final leg of a telecommunications network
last mile
98The local service provider facility where local cables connect to long-haul communication lines
central office (CO)
99The collection of interconnected switches and facilities owned by the provider inside the WAN cloud
toll network
100The portion of the network that links the access edge nodes back to the core network
backhaul network
101The two most common types of circuit-switched WAN technologies
PSTN and ISDN
102A legacy device that converts digital data into analog audio signals for transmission over standard telephone lines
Voiceband modem
103A device that provides high-speed internet access over ordinary copper telephone lines
DSL modem
104A device that provides high-speed data access over a cable television coaxial network
cable modem
105A high-speed connection technology that uses existing twisted-pair telephone lines
DSL
106WAN technology that uses a cable company coaxial cable to provide IP services
cable technology
107A digital-interface device used to connect DTE equipment to a digital circuit like a T1 or E1 line
CSU/DSU
108A device that translates electrical networking signals into optical signals for fiber transmission, and vice versa
optical converter
109The process of sending data sequentially, one bit at a time, over a communication channel
serial communication
110The North American digital transmission system standard, including line types like T1 and T3
T-carrier
111The European digital transmission system standard, including line types like E1 and E3
E-carrier
112A legacy packet-switching WAN technology that uses virtual circuits to connect remote sites
frame relay
113A legacy cell-switching WAN technology that transmits data in fixed 53-byte cells
asynchronous transfer mode (ATM)
114Unused optical fiber infrastructure that has been laid but is not currently transmitting light
dark fiber
115The use of Ethernet technology to connect networks across a metropolitan area network (MAN)
metropolitan Ethernet (Metro E)
116A technology that allows Ethernet frames to be encapsulated and transmitted across an MPLS core network
Ethernet over MPLS (EoMPLS)
117An Ethernet-based multipoint-to-multipoint VPN service delivered over an MPLS network
Virtual Private LAN service (VPLS)
118A high-performance routing technique that directs data from one node to the next based on short path labels rather than long network addresses
Multiprotocol Label Switching (MPLS)
119Routers within an MPLS network that forward packets based on labels rather than IP routing tables
label switched routers (LSRs)
120The router located at the customer site that connects directly to the service provider's network
Customer edge (CE) router
121The router at the service provider's edge that connects directly to the customer's edge router
Provider edge (PE) router
122A router inside the service provider's core network that forwards traffic but does not connect to customer routers
Internal provider (P) router
123A network device located at the provider's central office that aggregates multiple customer DSL connections
DSL access multiplexer (DSLAM)
124A protocol used to encapsulate Point-to-Point Protocol frames inside Ethernet frames, heavily used with DSL broadband
PPP over Ethernet (PPPoE)
125The international standard used for providing high-speed internet access via cable TV systems
Data over Cable Service Interface Specification (DOCSIS)
126A network architecture used by cable providers that combines optical fiber with coaxial cable
hybrid fiber-coaxial (HFC)
127A device at the cable company's headend that provides high-speed data services to subscriber cable modems
Cable Modem Termination System (CMTS)
128A generic term for any broadband network architecture using optical fiber to provide all or part of the local loop
Fiber to the x (FTTx)
129A network architecture where a fiber-optic connection reaches directly into a customer's residence
Fiber to the Home (FTTH)
130A network architecture where a fiber-optic connection reaches a multi-dwelling unit or business structure
Fiber to the Building (FTTB)
131A network architecture where fiber terminates at a street cabinet, and copper wire completes the final distance
Fiber to the Node/Neighborhood (FTTN)
132City-wide wireless internet access networks typically deployed by local governments
Municipal Wi-Fi
133What keeps VPN traffic private while transported across a public network?
encryption
134Two types of protocols used to create remote access VPNs
IPsec or SSL
135The device that typically terminates a site-to-site VPN tunnel
VPN gateway
136The four elements provided by the IPsec framework
confidentiality, integrity, origin authentication, and Diffie-Hellman
137A Cisco hardware security device that provides firewall, intrusion prevention, and VPN capabilities
Cisco Adaptive Security Appliance (ASA) firewall
138An acronym for a Small Office or Home Office network environment
SOHO
139Cisco's secure mobility client software used primarily to establish client-based VPN connections
Cisco AnyConnect
140A secure IPsec VPN connection established between two permanent locations, such as a branch and headquarters
Site-to-Site VPN
141A secure VPN connection allowing individual traveling or work-from-home users to access a private network over the internet
Remote access VPN
142A type of VPN that uses Transport Layer Security (TLS) to provide secure remote access, typically via a web browser
SSL VPN
143A secure suite of protocols used to authenticate and encrypt IP packets to provide secure communication over an IP network
IPsec
144A tunneling protocol developed by Cisco that can encapsulate a wide variety of network layer protocols inside point-to-point links
Generic Routing Encapsulation (GRE)
145A Cisco routing technology used to build multiple, dynamic, and scalable VPN tunnels between remote sites
Dynamic Multipoint VPN (DMVPN)
146A protocol that allows a single GRE interface to dynamically support multiple IPsec tunnels to different destinations
Multipoint Generic Routing Encapsulation (mGRE)
147A Cisco IOS interface type that simplifies the configuration of IPsec site-to-site VPNs by removing the need for crypto maps
Virtual Tunnel Interface (VTI)
148An algorithm used to securely exchange cryptographic keys over an insecure public channel
Diffie-Hellman
149The establishment of shared security attributes and keys between two network entities to support secure IPsec communication
Security Association (SA)
150An IPsec protocol that provides data integrity and origin authentication, but does not provide encryption
Authentication Header (AH)
151An IPsec protocol that provides encryption, origin authentication, and data integrity for VPN payloads
Encapsulation Security Protocol (ESP)
152An older, legacy symmetric-key encryption algorithm that uses a 56-bit key and is considered insecure today
DES
153An encryption algorithm that applies the DES cipher algorithm three times to each data block for increased security
3DES
154A modern, highly secure symmetric encryption algorithm widely used as the standard today
AES
155An older, software-optimized stream cipher alternative to DES
SEAL
156A family of cryptographic hash functions used to verify data integrity and ensure it has not been altered
Secure Hash Algorithm (SHA)
157A widely used cryptographic hash function producing a 128-bit hash value, now considered cryptographically vulnerable
Message-Digest 5 (MD5)
158A widely used asymmetric cryptographic algorithm utilized for secure data transmission and digital signatures
Rivest, Shamir, and Adleman (RSA)
159A secret string of text previously shared between two parties using a secure channel, used for authentication in IPsec VPNs
pre-shared secret key (PSK)
160The variation in the delay of received packets
jitter
161Traffic type that is smooth and benign but sensitive to drops and delays
voice traffic
162Traffic type that is bursty, greedy, drop sensitive, and delay sensitive
video traffic
163The three models for implementing QoS
Best-effort, IntServ, and DiffServ
164A QoS tool that determines the class of traffic to which packets or frames belong
classification
165A Cisco IOS congestion avoidance solution that monitors network traffic loads
WRED (Weighted Random Early Detection)
166The fixed amount of time required for a Digital Signal Processor (DSP) to compress a voice signal into digital form
code delay
167The time taken to fill a network packet payload with encoded voice or data before it is sent
packetization delay
168The time a packet spends waiting in a router's buffer before it can be transmitted out of an interface
queuing delay
169The time required to place all the physical bits of a packet onto the transmission media
serialization delay
170The time it takes for a signal to travel from the source to the destination over the transmission medium
propagation delay
171The latency introduced by a buffer used to smooth out variations in packet arrival times, crucial for VoIP
de-jitter delay
172The simplest QoS queuing method that buffers and forwards packets in the order of arrival
FIFO (First-In-First-Out)
173A QoS queuing method that automatically provides fair bandwidth allocation across all active network traffic flows
weighted fair queuing (WFQ)
174A QoS queuing mechanism that allows administrators to define traffic classes and assign guaranteed bandwidth to each
class-based weighted fair queuing (CBWFQ)
175A QoS queuing method that adds strict priority queuing to CBWFQ, ensuring voice traffic is sent before all other data
low latency queuing (LLQ)
176A QoS architecture model that requires applications to signal and reserve specific network resources along a path before sending data
IntServ
177A scalable QoS architecture model that marks individual packets for different levels of service without requiring path reservations
DiffServ
178The QoS process of identifying traffic types and modifying packet headers to indicate their priority level
classification and marking
179QoS mechanisms, like WRED, that drop lower-priority packets before a queue fills up entirely to prevent traffic congestion
congestion avoidance
180QoS mechanisms that determine the order in which packets are sent out an interface when queues build up during congestion
congestion management
181A 3-bit QoS field found in Layer 2 headers (like 802.1Q) used to indicate the priority of an Ethernet frame
class of service
182A 6-bit field in the IPv4 and IPv6 header used to specify the QoS priority level of a packet in the DiffServ model
differentiated code point (DSCP)
183The default QoS model where no special treatment, prioritization, or delivery guarantees are given to any traffic
best-effort
184A DSCP per-hop behavior marking that guarantees low latency, low jitter, and low loss, predominantly used for VoIP traffic
expedited forwarding
185A DSCP per-hop behavior marking that provides distinct classes of service and different drop probabilities for data traffic
assured forwarding
186The specific point in a network architecture where devices are explicitly trusted to correctly classify and mark QoS traffic
trust boundaries
187A QoS mechanism that buffers excess traffic to smooth out bursts and limits the outbound traffic rate to a specified speed
shaping
188A QoS mechanism that strictly drops or remarks traffic that exceeds a configured rate limit, without buffering the excess
policing
189A Cisco-proprietary Layer 2 protocol used to share hardware and OS information between directly connected Cisco devices
Cisco Discovery Protocol (CDP)
190What is the default state of CDP on Cisco devices?
Enabled by default
191The global configuration command used to enable CDP globally across an entire Cisco device
cdp run
192The interface configuration command used to enable CDP on a specific interface
cdp enable
193The command used to display global CDP timer and holdtime settings
show cdp
194The command used to display CDP status and configurations for specific interfaces
show cdp interface
195The command used to display a summary list of directly connected CDP devices
show cdp neighbors
196The command used to display detailed information about directly connected CDP devices, including their IP addresses
show cdp neighbors detail
197An open-standard, vendor-neutral Layer 2 protocol used to discover neighbor devices on a network
Link Layer Discovery Protocol (LLDP)
198The global configuration command used to enable LLDP globally on a device
lldp run
199A generic term or interface command concept used to activate LLDP functionality on an interface
lldp enable
200The interface configuration command used to allow an interface to send LLDP packets to neighbors
lldp transmit
201The interface configuration command used to allow an interface to process incoming LLDP packets from neighbors
lldp receive
202The command used to display global LLDP configuration and timer settings on a switch or router
show lldp
203The command used to display a summary list of directly connected LLDP neighbors
show lldp neighbors
204The command used to display highly detailed information about directly connected LLDP neighbor devices
show lldp neighbors detail
205The Privileged EXEC command used to manually configure the system time and date on a Cisco router or switch
clock set hh:mm:ss mm dd yyyy
206A networking protocol used to synchronize the clocks of computer systems over variable-latency data networks
Network Time Protocol (NTP)
207A numerical level indicating the distance and accuracy of an NTP time source from the highly accurate reference clock
Stratum
208What are authoritative high-precision timekeeping devices referred to in an NTP hierarchy?
Stratum 0 devices
209The command used to display the current time, date, and time zone configured on a network device
show clock
210The command used to display the current time and date, along with its designated time source (like NTP)
show clock detail
211The global configuration command used to specify the IP address of an external time source for synchronization
ntp server ip-address
212The command used to display the status of the device's connections to configured NTP servers
show ntp associations
213The command used to verify whether the device is successfully synchronized with an NTP server and display its stratum
show ntp status
214An application-layer protocol used heavily by administrators to manage, monitor, and configure network devices
Simple Network Management Protocol (SNMP)
215What are the three elements of an SNMP system?
SNMP manager, SNMP agents, and the MIB
216Software or hardware used by network administrators to monitor, manage, and configure network devices centrally
Network Management System (NMS)
217The software component running on the NMS that polls agents for data and receives unrequested trap alerts
SNMP Manager
218The software component running on a managed network device that responds to requests from the manager and sends traps
SNMP Agent
219A hierarchical, structured database residing on a managed device that stores its operational and configuration parameters
Management Information Base (MIB)
220A unique, hierarchical numerical string used in SNMP to specifically identify a variable or object within a MIB
Object Identifier (OID)
221An SNMP message sent by the manager to retrieve a single, specific variable from an agent
get-request
222An SNMP message sent by the manager to retrieve the next sequential variable in a MIB tree
get-next-request
223An SNMP message introduced in v2c used to efficiently retrieve large amounts of sequential data, like a routing table
get-bulk-request
224An SNMP message sent by an agent back to the manager containing the requested data
get-response
225An SNMP message sent by the manager to change or configure a specific value on the agent device
set-request
226A specific, readable or writable instance of data within a MIB that can be interacted with via SNMP
MIB Variable
227An unsolicited message sent actively by an agent to the manager to report a significant event, error, or threshold breach
SNMP Agent Trap
228The original version of SNMP, offering poor security by transmitting community strings in cleartext
SNMPv1
229Which version of SNMP provides both security models and security levels?
SNMPv3
230Which UDP port does the syslog protocol use?
UDP port 514
231What are the common destinations for captured syslog messages?
Logging buffer, console line, terminal line, and syslog server
232What is the default format of syslog messages on Cisco IOS software?
%facility-severity-MNEMONIC: description
233What command forces logged events to display the date and time?
service timestamps log datetime
234What tool allows an administrator to navigate directories and list files in flash memory or a disk?
Cisco Integrated File System (IFS)
235What command is used to view the available file systems on a Catalyst switch or Cisco router?
show file systems
236What command saves the running configuration to a TFTP server?
copy running-config tftp
237What command configures a router to load a new IOS image during bootup?
boot system