User's Guide

(reducing VM sprawl). Learn more about DCC at http://www.extremenetworks.com/product/data-
center-connect/.
DoS attack
Denial of Service attacks occur when a critical network or computing resource is overwhelmed so that
legitimate requests for service cannot succeed. In its simplest form, a DoS attack is indistinguishable
from normal heavy trac. ExtremeXOS software has configurable parameters that allow you to defeat
DoS attacks.
DSSS
Direct-Sequence Spread Spectrum is a transmission technology used in Local Area Wireless Network
(LAWN) transmissions where a data signal at the sending station is combined with a higher data rate bit
sequence, or chipping code, that divides the user data according to a spreading ratio. The chipping
code is a redundant bit pattern for each bit that is transmitted, which increases the signal's resistance to
interference. If one or more bits in the pattern are damaged during transmission, the original data can
be recovered due to the redundancy of the transmission. (Compare with FHSS (Frequency-Hopping
Spread Spectrum).)
EAP-TLS/EAP-TTLS
EAP-TLS Extensible Authentication Protocol - Transport Layer Security. A general protocol for
authentication that also supports multiple authentication methods, such as token cards, Kerberos, one-
time passwords, certificates, public key authentication and smart cards.
IEEE 802.1x specifies how EAP should be encapsulated in LAN frames.
In wireless communications using EAP, a user requests connection to a WLAN through an access point,
which then requests the identity of the user and transmits that identity to an authentication server such
as RADIUS The server asks the access point for proof of identity, which the access point gets from the
user and then sends back to the server to complete the authentication.
EAP-TLS provides for certificate-based and mutual authentication of the client and the network. It relies
on client-side and server-side certificates to perform authentication and can be used to dynamically
generate user-based and session-based WEP keys.
EAP-TTLS (Tunneled Transport Layer Security) is an extension of EAP-TLS to provide certificate-based,
mutual authentication of the client and network through an encrypted tunnel, as well as to generate
dynamic, per-user, per-session WEP keys. Unlike EAP-TLS, EAP-TTLS requires only server-side
certificates.
(See also PEAP (Protected Extensible Authentication Protocol).)
ESRP
Extreme Standby Router Protocol is an Extreme Networks-proprietary protocol that provides redundant
Layer 2 and routing services to users.
Extreme Defender for IoT
Extreme Defender for IoT provides unique in-line security for mission critical and/or vulnerable IoT
devices. Placed between the IoT device and the network, the Defender for IoT solution helps secure and
isolate IoT devices protecting them from internal and external hacking attempts, viruses, malware and
ransomware, DDoS attacks, and more. Designed to be simple and flexible, Defender for IoT can be
deployed over any network infrastructure to enable secure IoT management without significant
network changes.
Glossary