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EAPS
Extreme Automatic
Protection Switching. This is an Extreme Networks-proprietary version of the Ethernet
Automatic Protection Switching protocol that prevents looping Layer 2 of the network. This
feature is discussed in RFC 3619.
EAPS domain
An EAPS domain consists of a series of switches, or nodes, that comprise a single ring
in a network. An EAPS domain consists of a master node and transit nodes. The master node
consists of one primary and one secondary port. EAPS operates by declaring an EAPS domain on a
single ring.
EAPS link ID
Each common link in the EAPS network must have a unique link ID. The controller and
partner shared ports belonging to the same common link must have matching link IDs, and not
other instance in the network should have that link ID.
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.)
EBGP
Exterior Border Gateway
Protocol. EBGP is a protocol in the IP suite designed to exchange network reachability
information with BGP systems in other
autonomous systems. EBGP
works between different ASs.
ECMP
Equal Cost Multi Paths.
This routing algorithm distributes network traffic across multiple high-bandwidth
OSPF,
BGP, IS-IS, and static routes
to increase performance. The Extreme Networks implementation supports multiple equal cost
paths between points and divides traffic evenly among the available paths.
edge ports
In
STP, edge ports connect to non-STP devices such as routers,
endstations, and other hosts.
edge safeguard
Loop prevention and
detection on an edge port configured for
RSTP is called
edge safeguard. Configuring edge
safeguard on RSTP edge ports can prevent accidental or deliberate misconfigurations (loops)
resulting from connecting two edge ports together or from connecting a hub or other non-STP
switch to an edge port. Edge safeguard also limits the impact of broadcast storms that might
occur on edge ports. This advanced loop prevention mechanism improves network resiliency but
does not interfere with the rapid convergence of edge ports.
For more information about edge safeguard, see Configuring Edge
Safeguard in the ExtremeXOS 21.1 User Guide.
EDP
Extreme Discovery Protocol. EDP is a protocol used to gather information about
neighbor Extreme Networks switches. Extreme Networks switches use EDP to exchange topology
information.
EEPROM
Electrically erasable programmable read-only memory. EEPROM is a memory that can be
electronically programmed and erased but does not require a power source to retain
data.
EGP
Exterior Gateway
Protocol. EGP is an Internet routing protocol for exchanging reachability information between
routers in different
autonomous systems.
BGP is a more recent protocol that accomplishes this task.
election algorithm
In ESRP, this is a user-defined criteria to determine how the master and slave
interact. The election algorithm also determines which device becomes the master or slave and
how ESRP makes those decisions.
ELRP
Extreme Loop Recovery Protocol. ELRP is an Extreme Networks-proprietary protocol that
allows you to detect Layer 2 loops.
ELSM
Extreme Link Status Monitoring. ELSM is an Extreme Networks-proprietary protocol that
monitors network health. You can also use ELSM with Layer 2 control protocols to improve Layer
2 loop recovery in the network.
EMISTP
Extreme Multiple Instance Spanning Tree Protocol. This Extreme Networks-proprietary
protocol uses a unique encapsulation method for STP messages that allows a physical port to
belong to multiple STPDs.
EMS
Event Management System. This Extreme Networks-proprietary system saves, displays, and
filters events, which are defined as any occurrences on a switch that generate a log message
or require action.
encapsulation mode
Using
STP, you can configure ports within an STPD to accept specific BPDU
encapsulations. The three encapsulation modes are:
- 802.1D—This mode is used for backward compatibility with previous
STP versions and for compatibility with third-party switches using IEEE standard
802.1D.
- EMISTP—Extreme Multiple Instance Spanning Tree Protocol mode is an
extension of STP that allows a physical port to belong to multiple STPDs by assigning the
port to multiple VLANs.
- PVST+—This mode implements PVST+ in compatibility with third-party
switches running this version of STP.
ESRP
Extreme Standby Router Protocol. ESRP is an Extreme Networks-proprietary protocol that
provides redundant Layer 2 and routing services to users.
ESRP-aware device
This is an Extreme Networks device that is not running ESRP itself but that is
connected on a network with other Extreme Networks switches that are running ESRP. These
ESRP-aware devices also fail over.
ESRP domain
An ESRP domain allows multiple VLANs to be protected under a single logical entity. An
ESRP domain consists of one domain-master VLAN and zero or more domain-member
VLANs.
ESRP-enabled device
An ESRP-enabled device is an Extreme Networks switch with an ESRP domain and ESRP
enabled. ESRP-enabled switches include the ESRP master and slave switches.
ESRP extended mode
ESRP extended mode supports and is compatible only with switches running ExtremeXOS
software exclusively.
ESRP group
An ESRP group runs multiple instances of ESRP within the same VLAN (or broadcast
domain). To provide redundancy at each tier, use a pair of ESRP switches on the
group.
ESRP instance
You enable ESRP on a per domain basis; each time you enable ESRP is an ESRP
instance.
ESRP VLAN
A VLAN that is part of an ESRP domain, with ESRP enabled, is an ESRP VLAN.
ESS
Extended Service Set.
Several Basic Service Sets (BSSs) can be joined together to form one logical WLAN segment,
referred to as an extended service set (ESS). The SSID is used to identify the ESS. (See
BSS and
SSID.)
ethernet
This is the IEEE 802.3
networking standard that uses carrier sense multiple access with collision detection
(CSMA/CD). An Ethernet device that wants to transmit first checks the channel for a carrier,
and if no carrier is sensed within a period of time, the device transmits. If two devices
transmit simultaneously, a collision occurs. This collision is detected by all transmitting
devices, which subsequently delay their retransmissions for a random period. Ethernet runs at
speeds from 10 Mbps to 10 Gbps on full duplex.
event
Any type of occurrence
on a switch that could generate a log message or require an action. For more, see
syslog.