AAA - ✅✅Authentication, authorization and accounting
AAA Server - ✅✅Server providing authentication, authorization and accounting services
Access Control Entry (ACE) - ✅✅One line in an access control list (ACL)
access interface - ✅✅A LAN network design term that refers to a switch interface connected to end-
user devices
access layer - ✅✅In a Campus LAN design, the switches that connect directly to end-point devices
access link (WAN) - ✅✅A physical link between a service provider and its customer
access rate - ✅✅The speed at which bits are sent over an access link
accounting - ✅✅In security, the recording of access attempts
ACI - ✅✅Application Centric Infrastructure
ACL - ✅✅Access Control List
Active Directory - ✅✅A popular set of identity and directory services from Microsoft, used in part to
authenticate users
administrative distance - ✅✅In Cisco routers, a means for one router to choose between multiple
routes to reach the same subnet when those routes are learned by different routing protocols.
,agent - ✅✅Generally, an additional software process or component running in a computing device
for some specific purpose
agent-based architecture - ✅✅An architecture that uses a software agent inside the device being
managed
agentless architecture - ✅✅An architecture that does not need a software agent
amplification attack - ✅✅A reflection attack that leverages a service on the reflector to generate and
reflect huge volumes of reply traffic to the victim
Ansible - ✅✅A popular configuration management application
Ansible inventory - ✅✅Device host names along with information about each device
Ansible playbook - ✅✅Files with actions and logic about what Ansible should do
anti-replay - ✅✅Preventing a man in the middle from copying and later replaying the packets sent by
a legitimate user, for the purpose of appearing to be a legitimate user
antivirus - ✅✅Software that monitors files transferred by any means, to look for content that can be
used to place a virus into the computer
APIC - ✅✅Application Policy Infrastructure Controller
APIC-EM - ✅✅Application Policy Infrastructure Controller -Enterprise Module
Application Centric Infrastructure (ACI) - ✅✅Cisco's data center SDN solution
,Application Policy Infrastructure Controller - Enterprise Module (APIC-EM) - ✅✅The software that
plays the role of controller in an enterprise network of Cisco devices
application programming interface (API) - ✅✅A software mechanism that enables software
components to communicate with each other
application signature - ✅✅With Network Based Application Recognition (NBAR), the definition of a
combination of matchable fields that identify as characteristics of a specific application
Application Visibility and Control (AVC) - ✅✅A firewall device with advance features (IPS, malware
detection, VPN termination, etc.)
application-specific integrated circuit (ASIC) - ✅✅An integrated circuit (chip) designed for a specific
purpose of application.
AR - ✅✅Access Rate
ARP - ✅✅Address Resolution Protocol. An internet protocol used to map an IP address to a MAC
address
ARP ACL - ✅✅A configuration feature on Cisco LAN switches that define MAC and IP that will be
filtered
ARP Reply - ✅✅An ARP message used to supply information about an ARP request. A device
providing its MAC address in reply to a request
ARP Request - ✅✅An ARP message used to request information from another host located on the
same subnet or broadcast domain
ARP Table - ✅✅A list of IP addresses of neighbors on the same VLAN, along with their MAC addresses
, ASAv - ✅✅A Cisco ASA firewall software image that runs as a virtual machine rather than on
hardware
ASIC - ✅✅Application Specific Integrated Circuit
authentication - ✅✅In security, the verification of the identity of a person, device or process
Authoritative DNS server - ✅✅The DNS server with the record that lists the address that corresponds
to a domain name (A Record) for that domain
authorization - ✅✅In security, the determination of the rights allowed for a particular user or device
autonomous system (AS) - ✅✅An internetwork that is managed by one organization
autonomous system number (ASN) - ✅✅A number used by BGP to identify a routing domain, often a
single enterprise or organization.
AutoQoS - ✅✅In Cisco switches and routers, an IOS feature that configures a variety of QoS features
with useful settings as defined by design guides
bandwidth - ✅✅The speed at which bits can be sent and received over a link
bandwidth profile - ✅✅In MetroEthernet, a contractual definition of the amount of traffic that the
customer can send into the service and receive out of the service
Brownfield - ✅✅A term that refers to the choice to add new configuration to hardware and software
that are already in use, rather than adding new hardware and software specifically for a new project
brute-force attack - ✅✅An attack where a malicious user runs software that tries every possible
combination of letters, numbers and special characters to guess a user's password