Term 181
Elliptic curve cryptography
Elliptic curve cryptography is a type of public-key cryptography that uses the mathematics of elliptic curves to create smaller, faster, and more efficient cryptographic keys compared to older methods like RSA.
Acronym study
Terms 181–210 of 716 CCNA acronyms and key terms. Each entry includes a plain-English definition and a link to the full 800-word glossary page with exam context and practice questions.
Term 181
Elliptic curve cryptography is a type of public-key cryptography that uses the mathematics of elliptic curves to create smaller, faster, and more efficient cryptographic keys compared to older methods like RSA.
Term 182
A Cisco IOS command that sets a password to protect privileged EXEC mode (enable mode) using a strong, one-way cryptographic hash (MD5 by default), replacing the weaker 'enable password' command.
Term 183
Encapsulation is the process of wrapping data with protocol headers and trailers before sending it across a network.
Term 184
Encryption is the process of converting readable data into a secret code to prevent unauthorized access.
Term 185
Enhanced Interior Gateway Routing Protocol (EIGRP) is a Cisco-proprietary advanced distance-vector routing protocol that calculates the best path through a network using multiple metrics, with fast convergence and loop-free routing.
Term 186
Err-disabled is a switch port state that occurs when the switch detects a critical error on that port and automatically shuts it down to protect the network.
Term 187
ESP (Encapsulating Security Payload) is a core protocol in IPsec that provides confidentiality, data integrity, and authentication for VPN traffic by encrypting and optionally authenticating the payload of IP packets.
Term 188
ESP (Encapsulating Security Payload) provides confidentiality, data origin authentication, connectionless integrity, and anti-replay protection for IP packets.
Term 189
EtherChannel is a technology that bundles multiple physical Ethernet links into a single logical link to increase bandwidth and provide redundancy.
Term 190
Ethernet is a wired networking technology that connects devices like computers, printers, and servers to each other and to the internet using cables.
Term 191
EUI-64 is a method for creating a 64-bit interface identifier from a 48-bit MAC address, used to form an IPv6 link-local or stateless address auto-configuration (SLAAC) address.
Term 192
An evil twin attack is a rogue wireless access point that impersonates a legitimate network to intercept or manipulate user traffic.
Term 193
An exam domain is a major topic area or category of knowledge that a certification exam tests, like a chapter in a study guide.
Term 194
An exit code (or return code) is a numeric value that a program or script sends back to the operating system after it finishes running, signaling whether it succeeded or failed.
Term 195
The exit interface is the network interface through which a router forwards a packet out of the router after matching a route in its routing table.
Term 196
ExpressRoute is a cloud service that creates a private, dedicated network connection between your on-premises infrastructure and Microsoft Azure, bypassing the public internet for faster, more reliable data transfer.
Term 197
An extended access control list (ACL) is a set of rules that filters network traffic based on source and destination IP addresses, protocol type, and port numbers, providing more granular control than a standard ACL.
Term 198
An Extended Service Set Identifier (ESSID) is the name of a wireless network that uses multiple access points to cover a larger area, allowing devices to roam seamlessly between them.
Term 199
Extensible Authentication Protocol (EAP) is a flexible authentication framework used in network access control, particularly in wireless and point-to-point connections, that supports multiple authentication methods without requiring changes to the underlying protocol.
Term 200
EAP over LAN (EAPoL) is a protocol that carries authentication messages between a device and a network access point before the device is allowed to connect to the network.
Term 201
Extensible Markup Language (XML) is a markup language that defines rules for encoding documents in a format that is both human-readable and machine-readable.
Term 202
Fail2ban is a security tool that monitors log files for repeated authentication failures and temporarily bans the offending IP addresses using firewall rules.
Term 203
Failover is the automatic switching to a backup system when the primary system fails, ensuring continuous operation and minimal downtime.
Term 204
Failover routing is a network design that automatically redirects traffic to a backup path when the primary path fails, keeping services available.
Term 205
A backup route in an EIGRP network that is immediately available if the primary route fails, without needing to run the Diffusing Update Algorithm (DUAL) again.
Term 206
First Hop Redundancy Protocol (FHRP) is a network protocol that provides automatic default gateway failover for hosts on a subnet.
Term 207
Fiber internet is a broadband connection that uses strands of glass or plastic to transmit data as pulses of light, offering higher speeds and more reliable service than traditional copper-based connections.
Term 208
Fibre Channel is a high-speed networking technology used to connect computer data storage to servers, enabling fast and reliable data transfer in enterprise data centers.
Term 209
File association is the operating system configuration that links a specific file type or extension to a default program that can open, edit, or execute that file.
Term 210
File Transfer Protocol (FTP) is a standard network protocol used to transfer files between a client and a server over a TCP/IP network.