CCNP ENCOR Vocab Flashcards
802.1p
An IEEE specification that defines the use of the 3-bit Priority Code Point (PCP) field to provide different classes of service. The PCP field is contained within the TCI field, which is part of the 802.1Q header.
802.1Q
An IEEE specification that defines two 2-byte fields, Tag Protocol Identifier (TPID) and Tag Control Information (TCI), that are inserted within an Ethernet frame.
802.1x
An IEEE standard for port-based network access control (PNAC) that provides an authentication mechanism for local area networks (LANs) and wireless LANs (WLANs).
access control list (ACL)
mechanism that provides packet classification for quality of service
(QoS), routing protocols, and basic firewall functionality.
access layer
The network layer that gives endpoints and users direct access to the network.
access port
A switch port that is configured for only one specific VLAN and generally connects end-user devices.
address family
A major classification of type of network protocol, such as IPv4, IPv6, or
VPNv4.
address resolution protocol (ARP)
protocol that resolves a MAC address to a specific
IP address.
administrative distance
rating of trustworthiness for a route. Generally, it is associated
with the routing process that installs the route into the RIB.
AMP for Networks
AMP running on Cisco Secure Firewall appliances and dedicated Cisco
AMP appliances for network malware defense.
amplitude
height from the top peak to the bottom peak of a signal’s waveform; also
known as the peak-to-peak amplitude.
anchor controller
The original controller a client was associated with before a Layer 3 intercontroller roam. An anchor controller can also be used for tunneling clients on a guest WLAN or with a static anchor. Traffic is tunneled from the client’s current controller (the foreign controller) back to the anchor.
application programming interface (API)
A set of functions and procedures used for configuring
or monitoring computer systems, network devices, or applications that involves programmatically interacting through software. It can be used for connecting to individual devices or multiple devices simultaneously.
area border router (ABR)
A router that connects an OSPF area to Area 0 (that is, the backbone
area).
AS_Path
BGP attribute used to track the autonomous systems a network has been advertised through as a loop-prevention mechanism.
AS path access control list (ACL)
An ACL based on regex for identifying BGP routes based on the AS path and used for direct filtering or conditional matching in a route map.
atomic aggregate
BGP path attribute which indicates that a prefix has been summarized,
and not all of the path information from component routes was included in the aggregate.
authentication, authorization, and accounting (AAA)
An architectural framework that enables secure network access control for users and devices.
authentication server (AS)
An 802.1x entity that authenticates users or clients based on
their credentials, as matched against a user database. In a wireless network, a RADIUS server is an AS.
authenticator
An 802.1x entity that exists as a network device that provides access to the network. In a wireless network, a WLC acts as an authenticator.
autonomous AP
A wireless AP operating in a standalone mode, such that it can provide a
fully functional BSS and connect to the DS.
autonomous system (AS)
A set of routers running the same routing protocol under a single
realm of control and authority.
backbone area
The OSPF Area 0, which connects to all other OSPF areas. The backbone area is the only area that should provide connectivity between all other OSPF areas.
backup designated router (BDR)
A backup pseudonode that maintains the network segment’s
state to replace the DR in the event of its failure.
band
A contiguous range of frequencies.
bandwidth
The range of frequencies used by a single channel or a single RF signal.
beamwidth
A measure of the angle of a radiation pattern in both the E and H planes, where the signal strength is 3 dB below the maximum value.
BGP community
A well-known BGP attribute that allows for identification of routes for later
actions such as identification of source or route filtering/modification.
BGP multihoming
method of providing redundancy and optimal routing that involves adding
multiple links to external autonomous systems.
BPDU filter
STP feature that filters BPDUs from being advertised/received across the configured port.
BPDU guard
STP feature that places a port into an ErrDisabled state if a BPDU is
received on a portfast-enabled port.
bridge protocol data unit (BPDU)
A network packet that is used to identify a hierarchy and
notify of changes in the topology.
broadcast domain
A portion of a network where a single broadcast can be advertised or
received.
building block
A distinct place in the network (PIN) such as the campus end-user/endpoint block, the WAN edge block, the Internet edge block, or the network services block. The components of each building block are the access layer, the distribution layer, and/or the core (backbone) layer. Also known as a network block or a place in the network (PIN).
CAPWAP
standards-based tunneling protocol that defines communication between a lightweight AP and a wireless LAN controller.
carrier signal
The basic, steady RF signal that is used to carry other useful information.
channel
An arbitrary index that points to a specific frequency within a band.
Cisco Advanced Malware Protection (AMP)
Cisco malware analysis and protection solution that goes beyond point-in-time detection and provides comprehensive protection for organizations across the full attack continuum: before, during, and after an attack.
Cisco Express Forwarding (CEF)
method of forwarding packets in hardware through the
use of the FIB and adjacency tables. CEF is much faster than process switching.
Cisco Identity Services Engine (ISE)
Cisco security policy management platform that provides highly secure network access control to users and devices across wired, wireless, and VPN connections. It allows for visibility into what is happening in the network, such as who is connected (endpoints, users, and devices), which applications are installed and running on endpoints (for posture assessment), and much more.
Cisco SAFE
A framework that helps design secure solutions for the campus, data center, cloud, WAN, branch, and edge.
Cisco Secure Client
VPN client that is an 802.1x supplicant that can perform posture
validations and that provides web security, network visibility into endpoint flows within Cisco Secure Network Analytics, and roaming protection with Cisco Umbrella.
Cisco Secure Email
Cisco solution that enables users to communicate securely via email
and helps organizations combat email security threats with a multilayered approach across the attack continuum.
Cisco Secure Firewall
next-generation firewall (NGFW) with legacy firewall capabilities
such as stateful inspection as well as integrated intrusion prevention, application-level inspection, and techniques to address evolving security threats, such as advanced malware and application-
layer attacks.
Cisco Secure Malware Analytics
malware sandbox solution.
Cisco Secure Network Analytics
Cisco collector and aggregator of network telemetry data (NetFlow data) that performs network security analysis and monitoring to automatically detect threats that manage to infiltrate a network as well as threats that originate within a network.
Cisco Secure Web Appliance
An all-in-one web gateway that includes a wide variety of protections that can block advanced threats from both suspicious and legitimate websites.
Cisco Talos
The Cisco threat intelligence organization
Cisco TrustSec
next-generation access control enforcement solution developed by
Cisco that performs network enforcement by using Security Group Tags (SGTs) instead of IP addresses and ports. In SD-Access, Cisco TrustSec Security Group Tags are referred to as Scalable Group Tags.
Cisco Umbrella
Cisco solution that blocks requests to malicious Internet destinations
(domains, IP addresses, URLs) using Domain Name System (DNS).
Client density
The relative number of client devices served by an AP and its antenna, as determined by the antenna’s RF coverage pattern.
collision domain
set of devices in a network that can transmit data packets that can collide with other packets sent by other devices (that is, devices that can detect traffic from other devices using CSMA/CD).
command-line interface (CLI)
A text-based user interface for configuring network devices
individually by inputting configuration commands.
Common Spanning Tree (CST)
single spanning-tree instance for the entire network, as
defined in the 802.1D standard.
configuration BPDU
The BPDU that is responsible for switches electing a root bridge and
communicating the root path cost so that a hierarchy can be built.
container
isolated environment where containerized applications run. It contains the application along with the dependencies that the application needs to run. It is created by a container engine running a container image.
container image
file created by a container engine that includes application code along with its dependencies. Container images become containers when they are run by a container engine.
content addressable memory (CAM)
high-performance table used to correlate MAC addresses to switch interfaces that they are attached to.
control plane policing (CoPP)
policy applied to the control plane of a router to protect
the CPU from high rates of traffic that could impact router stability
cookbook
Chef container that holds recipes.
core layer
network layer, also known as the backbone, that provides high-speed connectivity between distribution layers in large environments.
Datagram Transport Layer Security (DTLS)
communications protocol designed to provide authentication, data integrity, and confidentiality for communications between two
applications, over a datagram transport protocol such as User Datagram Protocol (UDP). DTLS is based on TLS, and it includes enhancements such as sequence numbers and retransmission
capability to compensate for the unreliable nature of UDP. DTLS is defined in IETF RFC 4347.
dBd
dB-dipole, the gain of an antenna, measured in dB, as compared to a simple dipole antenna.
dBi
dB-isotropic, the gain of an antenna, measured in dB, as compared to an isotropic reference antenna.
dBm
dB-milliwatt, the power level of a signal measured in dB, as compared to a reference signal power of 1 milliwatt.
dead interval
The amount of time required for a hello packet to be received for the neighbor to be deemed healthy. Upon receipt, the value resets and decrements toward zero.
decibel (dB)
logarithmic function that compares one absolute measurement to another.
demodulation
The receiver’s process of interpreting changes in the carrier signal to recover the original information being sent.
dipole
An omnidirectional antenna composed of two wire segments.
designated port (DP)
network port that receives and forwards BPDUs to other downstream
switches.
OSPF designated router (DR)
A pseudonode to manage the adjacency state with other routers on the broadcast network segment.
DevNet
single place to go to enhance or increase skills with APIs, coding, Python, and even controller concepts.
PIM designated router (DR)
Protocol Independent-Sparse Mode (PIM-SM) router that is elected in a LAN segment when multiple PIM-SM routers exist to prevent the sending of duplicate multicast traffic into the LAN or the RP.
direct sequence spread spectrum (DSSS)
wireless LAN method in which a transmitter uses a single fixed, wide channel to send data.
Differentiated Services Code Point (DSCP)
6-bit field within the DiffServ field that allows for classification of up to 64 values (0 to 63).
Differentiated Services (DiffServ)
field that uses the same 8 bits of the IP header that
were previously used for the ToS and IPv6 Traffic Class fields. This allows it to be backward compatible with IP Precedence. The DiffServ field is composed of a 6-bit Differentiated Services Code Point (DSCP) field that allows for classification of up to 64 values (0 to 63) and a
2-bit Explicit Congestion Notification (ECN) field.
directional antenna
A type of antenna that propagates an RF signal in a narrow range of
directions.
directly attached static route
static route that defines only the outbound interface for
the next-hop device.
discontiguous network
OSPF network where Area 0 is not contiguous and generally
results in routes not being advertised pervasively through the OSPF routing domain.
distance vector routing protocol
protocol that selects the best path based on
next hop and hop count.
Distance-vector routing protocols use the Bellman–Ford algorithm to calculate the best route
Examples: RIP, RIPv2, IGRP, EIGRP
distribute list
list used for filtering routes with an ACL for a specific BGP neighbor.
distribution layer
network layer that provides an aggregation point for the access layer
and acts as a services and control boundary between the access layer and the core layer.
downstream
Away from the source of a tree and toward the receivers.
downstream interface
interface that is used to forward multicast traffic down the tree,
also known as the outgoing interface (OIF).
dynamic rate shifting (DRS)
mechanism used by an 802.11 device to change the modulation
coding scheme (MCS) according to dynamic RF signal conditions.
Dynamic Trunking Protocol (DTP)
protocol that allows for the dynamic negotiation of trunk ports.
E plane
“elevation” plane, which passes through an antenna that shows a side view of the radiation pattern.
eBGP session
BGP session maintained with BGP peers from a different autonomous system.
effective isotropic radiated power (EIRP)
resulting signal power level, measured in dBm, of the combination of a transmitter, cable, and an antenna, as measured at the antenna.
egress tunnel router (ETR)
router that de-encapsulates LISP-encapsulated IP packets
coming from other sites and destined to EIDs within a LISP site.
Embedded Event Manager (EEM)
An on-box automation tool that allows scripts to automatically
execute, based on the output of an action or an event on a device.
embedded WLC deployment
wireless network design that places a WLC in the access
layer, co-located with a LAN switch stack, near the APs it controls.
endpoint
device that connects to a network, such as a laptop, tablet, IP phone, personal computer (PC), or Internet of Things (IoT) device.
endpoint identifier (EID)
The IP address of an endpoint within a LISP site.
enhanced distance vector routing protocol
routing protocol that selects the best path based on next hop, hop count, and other metrics, such as bandwidth and delay.
equal-cost multipathing
installation of multiple best paths from the same routing protocol
with the same metric that allows for load-balancing of traffic across the paths.
ERSPAN
Encapsulated Remote Switched Port Analyzer, a tool for capturing network traffic on a remote device and sending the traffic to the local system via Layer 3 (routing) toward a local port that would be attached to some sort of traffic analyzer.
EtherChannel bundle
logical interface that consists of physical member links to increase a
link’s bandwidth while preventing forwarding loops.
Extensible Authentication Protocol (EAP)
standardized authentication framework defined by RFC 4187 that provides encapsulated transport for authentication parameters.
Extensible Markup Language (XML)
human-readable data format that is commonly used
with web services.
feasibility condition
an EIGRP condition under which, for a route to be considered a backup route, the reported distance received for that route must be less than the feasible distance calculated locally. This logic guarantees a loop-free path.
feasibility successor
an EIGRP route that satisfies the feasibility condition and is maintained as a backup route.
feasible distance
an EIGRP metric value for the lowest-metric path to reach a destination
Firepower Threat Defense (FTD) software image
single unified image in which the ASA software image and the Cisco Secure IPS image are merged. It is supported on all Cisco Secure Firewall and ASA 5500-X appliances (except the 5585-X).
first-hop redundancy protocol
protocol that creates a virtual IP address on a router or a multilayer device to ensure continuous access to a gateway when there are redundant devices.
first-hop router (FHR)
router that is directly attached to the source, also known as the
root router. It is responsible for sending register messages to the RP.
floating static route
static route with an elevated AD so that it is used only as a backup in
the event that a routing protocol fails or a lower-AD static route is removed from the RIB.
foreign controller
The current controller that a client is associated with after a Layer 3 intercontroller roam. Traffic is tunneled from the foreign controller back to an anchor controller so that the client retains connectivity to its original VLAN and subnet.
forward delay
amount of time that a port stays in a listening and learning state.
Forwarding Information Base (FIB)
The hardware programming of a forwarding table. The
FIB uses the RIB for programming.
frequency
The number of times a signal makes one complete up and down cycle in 1 second.
fully specified static route
A static route that specifies the next-hop IP address and the outbound interface.
gain
A measure of how effectively an antenna can focus RF energy in a certain direction.
GitHub
An efficient and commonly adopted way of using version control for code and sharing code repositories.
grain
In SaltStack, code that runs on nodes to gather system information and report back to the master.
H plane
The “azimuth” plane, which passes through an antenna that shows a top-down view of the radiation pattern.
hello interval
The frequency at which hello packets are advertised out an interface.
hello packets
Packets that are sent out at periodic intervals to detect neighbors for establishing adjacency and ensuring that neighbors are still available.
hello time
The time interval for which a BPDU is advertised out of a port.
hello timer
The amount of time between the advertisement of hello packets and when they are sent out an interface.
hertz (Hz)
A unit of frequency equaling one cycle per second.
host pool
The IP subnet, SVI, and VRF information assigned to a group of hosts that share the same policies.
hypervisor
Virtualization software that creates VMs and performs the hardware abstraction that allows multiple VMs to run concurrently.
iBGP session
A BGP session maintained with BGP peers from the same autonomous system.
IGMP snooping
A mechanism to prevent multicast flooding on a Layer 2 switch.
in phase
The condition when the cycles of two identical signals are in sync with each other.
incoming interface (IIF)
The only type of interface that can accept multicast traffic coming
from the source. It is the same as the RPF interface.
ingress tunnel router (ITR)
A router that LISP-encapsulates IP packets coming from EIDs
that are destined outside the LISP site.
inside global
The public IP address that represents one or more inside local IP addresses to the outside.
inside local
The actual private IP address assigned to a device on the inside network(s).
integrated antenna
very small omnidirectional antenna that is set inside a device’s outer
case.
inter-area route
An OSPF route learned from an ABR from another area. These routes are built based on type 3 LSAs.
intercontroller roaming
Client roaming that occurs between two APs that are joined to two
different controllers.
interface priority
The reference value for an interface to determine preference for being elected as the designated router.
internal spanning tree (IST)
The first MSTI in the MST protocol. The IST is responsible for building a CST across all VLANs, regardless of their VLAN membership. The IST contains advertisements for other MSTIs in its BPDUs.
Internet Group Management Protocol (IGMP)
The protocol used by receivers to join multicast groups and start receiving traffic from those groups.
Internet Key Exchange (IKE)
A protocol that performs authentication between two endpoints
to establish security associations (SAs), also known as IKE tunnels. IKE is the implementation of ISAKMP using the Oakley and Skeme key exchange techniques.
Internet Protocol Security (IPsec)
A framework of open standards for creating highly secure VPNs using various protocols and technologies for secure communication across unsecure networks such as the Internet.
Internet Security Association and Key Management Protocol (ISAKMP)
A framework for authentication and key exchange between two peers to establish, modify, and tear down SAs that is designed to support many different kinds of key exchanges. ISAKMP uses UDP port 500 to communicate between peers.
intra-area route
An OSPF route learned from a router within the same area. These routes are built based on type 1 and type 2 LSAs.
intracontroller roaming
Client roaming that occurs between two APs joined to the same
controller.
IP SLA
An on-box diagnostic tool that executes probes to monitor network devices and application performance.
isotropic antenna
An ideal, theoretical antenna that radiates RF equally in every direction.
JavaScript Object Notation (JSON)
Notation used to store data in key/value pairs that is
said to be easier to work with and read than XML.
K values
Values that EIGRP uses to calculate the best path.
LACP interface priority
An attribute assigned to a switch port on an LACP primary switch
to identify which member links are used when there is a maximum link.
LACP system priority
An attribute in an LACP packet that provides priority to one switch
over another to control which links are used when there is a maximum link.
last-hop router (LHR)
A router that is directly attached to the receivers, also known as a leaf
router. It is responsible for sending PIM joins upstream toward the RP or to the source after an SPT switchover.
Layer 2 forwarding
The forwarding of packets based on the packets’ destination Layer 2
addresses, such as MAC addresses.
Layer 2 roam
An intercontroller roam where the WLANs of the two controllers are configured for the same Layer 2 VLAN ID; also known as a local-to-local roam.
Layer 3 forwarding
The forwarding of packets based on the packets’ destination IP
addresses.
Layer 3 roam
An intercontroller roam where the WLANs of the two controllers are configured for different VLAN IDs; also known as a local-to-foreign roam. To support the roaming client, a tunnel is built between the controllers so that client data can pass between the client’s current controller and its original controller.
lightweight AP
A wireless AP that performs real-time 802.11 functions to interface with wireless clients, while relying on a wireless LAN controller to handle all management functions.
link budget
The cumulative sum of gains and losses measured in dB over the complete RF signal path; a transmitter’s power level must overcome the link budget so that the signal can reach a receiver effectively.
link-state routing protocol
A routing protocol that contains a complete view of the topology,
where every router can calculate the best path based on its copy of the topology.
Examples: OSPF, IS-IS
LISP router
router that performs the functions of any or all of the following: ITR, ETR, PITR, and/or PETR.
LISP site
A site where LISP routers and EIDs reside.
load-balancing hash
An algorithm for balancing network traffic across member links.
Loc-RIB table
The main BGP table that contains all the active BGP prefixes and path attributes that is used to select the best path and install routes into the RIB.
local bridge identifier
A combination of the advertising switch’s bridge system MAC, the
system ID extension, and the system priority of the local bridge.
local mode
The default mode of a Cisco lightweight AP that offers one or more functioning BSSs on a specific channel.
Locator/ID Separation Protocol (LISP)
routing architecture and data and control plane protocol that was created to address routing scalability problems on large networks.
MAC address table
A table on a switch that identifies the switch port and VLAN with
which a MAC address is associated for Layer 2 forwarding.
