Network Terms "E"

Network Glossary and acronym's

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

.EDB file

Exchange 2007's database engine is referred to as the Extensible Storage Engine (ESE). ESE is a transactional database that writes information into RAM memory and into a log file. Once it is in the log file, it will be written to disk. There are a number of files used to store information:

An .edb file is located in the actual database itself. All of a user's messages, folders, public folders, contacts, appointment information, etc. is all stored on the .edb file. An .edb file size can exceed multiple GB.
A .log file is an ESE transaction log file. All .log files are 1 MB.
A .jrs file is a reserve log file which is used to commit any transactions that are still in memory in the event of the server running out of disk space. All .jrs files are 1 MB.
A .chk file is used to identify which log files have been committed to the database. The size of .chk file varies from 2-3 KB.

The ESE takes the following steps to write information into database files:

The ESE writes a message into memory RAM when it arrives at the server.
At the same time that information is written to RAM, it's written into the current .log file. All current log files are named E00.log. The information is written in a sequential format until the log file is full. When the log file is full, it will be renamed.
Once it has been committed to the log file, the information is written to the .edb file.
The checkpoint file is updated to indicate that the transaction log that has been committed to the database.

EAP (Extensible Authentication Protocol)

EAP is an authentication protocol (an extension of PPP). It is a set of interface standards that provide various authentication methods (smartcards, biometrics, and digital certificates), define access definitions, providing protection mechanisms and custom solutions, and does not maintain a database of user accounts and passwords.

EAPoL (Extensible Authentication Protocol over LAN)

The Extensible Authentication Protocol over LAN is used for authentication of 802.1X port access control over either wired or wireless LANs.

Eavesdropping

Eavesdropping is the act of capturing and examining traffic on a network cable. Eavesdropping is the primary security vulnerability of networking systems using 802.11 technology. On wireless networks, eavesdropping is made more difficult by using WEP keys.

Fiber optic cable is the most resistant to tapping and eavesdropping. Fiber optic cable transmits light pulses rather than electricity to communicate. Thus, it is not susceptible to most forms of interference or wire tapping technologies. ThickNet (10Base5 coax), 10Base2 (ThinNet coax), and 10BaseT (STP and UTP) are very susceptible to tapping and eavesdropping.

EBGP (External BGP)

External BGP (EBGP) is used by BGP to route information between autonomous systems.

Edge Rules agent

Transport policy agents apply transport policies to e-mails within an Exchange organization. There are two types of transport policy agents in Exchange 2007:

A Transport Rules agent runs on a Hub Transport server and implements policies set by administrators to all e-mail that travels in and out of an Exchange organization.
An Edge Rules agent runs on an Edge Transport server and helps control spam and unwanted mail flow within an organization.

Edge Transport server

The Edge Transport server handles all Internet-facing mail flow and provides Simple Mail Transfer Protocol (SMTP) relay and smart host services for the Exchange 2007 organization.

EDirectory

NetWare 4.x and higher uses a directory service called eDirectory (formerly called Novell Directory Services (NDS)). User accounts are configured in the directory. eDirectory can also run on other servers such as Windows and Linux.

Effective permission

The combined rights a user has to perform specific network functions and access network resources.

EGP (Exterior Gateway Protocol)

Exterior Gateway Protocol (EGP) is a routing protocol that exchanges routing information between autonomous systems. BGP is the most common EGP protocol.

EIDE (Enhanced Integrated Drive Electronics)

A standard electronic interface that allows a computer to communicate with a storage device such as the hard drive or a CD-ROM drive.

EISA (Extended Industry Standard Architecture)

A 32-bit I/O bus slot providing compatibility with 386 through Pentium machines. EISA buses:

Have a maximum throughput rate of 33 MB/s.
Offer bus mastering which is a mini-processor on the expansion card. The mini-processor assumes the task from the CPU of transferring data to and from memory.
Offer a second row of pins to a standard ISA bus.
Provide backward compatibility with ISA cards.
Allow EISA cards to take advantage of both rows of pins (the 32-bit data path) to improve transfer rates and increase addressable memory.
Allow for automatic configuration of system resources (addresses, DMA channels and IRQs).
Support sharing of system resources.
Allow multiple EISA cards to share the same interrupt.
EISA supports multiprocessing by allowing more than one CPU to share the bus.
Are usually black, though they are sometimes white.

Electromagnetic Interference (EMI)

The disruption of one electronic device, caused by an electromagnetic field (in the radio frequency spectrum) generated by another electronic device.

E-mail Address policies

E-mail Address policies are used to generate e-mail addresses for Exchange recipients within an Exchange 2007 organization. Policies can be used to generate e-mail addresses for a number of environments, such as SMTP, X400, Lotus Notes, or Novell GroupWise.

E-mail client

An e-mail client is a software application that supports specific protocols and provides the user with an interface to a server.

Emergency Repair Disk (ERD)

A backup disk that can provide the necessary files to bring back the Windows operating system in the case of a disk disaster running the Windows operating system. You create an ERD using Windows 2000.

EMI (Electromagnetic Interference)

The disruption of one electronic device, caused by an electromagnetic field (in the radio frequency spectrum) generated by another electronic device.

Encapsulating Security Payload (ESP)

Encapsulating Security Payload (ESP) is one of two services comprising IPSec. ESP supports both authentication of the sender and is used primarily to encrypt and secure the data transferred between IPSec partners.

Encapsulation

The process of adding an additional header to a packet before transporting the packet onto the network. For example, NetBIOS can be encapsulated with an IP header.

Encryption

A security technique that uses a cryptographic algorithm to encode information so that only someone with the proper key can unencode it.

Enhanced Integrated Drive Electronics (EIDE)

A standard electronic interface that allows a computer to communicate with a storage device such as the hard drive or a CD-ROM drive.

Enhanced Small Device Interface (ESDI)

A type of hard disk that uses CHS addressing and has a 1024 cylinder limitation. ESDI hard disks are predecessors of the newer IDE disks.

ERD (Emergency Repair Disk)

ErrorControl levels

The values Windows uses to determine what to do in case of an error in loading or initializing drivers. The levels are 0x0 (ignore the error), 0x1 (display an error message then ignore the error), 0x2 (use the LastKnownGood control set and restart), 0x3 (stop the boot sequence and display an error message).

ESDI (Enhanced Small Device Interface)

A type of hard disk that uses CHS addressing and has a 1024 cylinder limitation. ESDI hard disks are predecessors of the newer IDE disks.

ESE (Extensible Storage Engine)

An .edb file is located in the actual database itself. All of a user's messages, folders, public folders, contacts, appointment information, etc. is all stored on the .edb file. An .edb file size can exceed multiple GB.
A .log file is an ESE transaction log file. All .log files are 1 MB.
A .jrs file is a reserve log file which is used to commit any transactions that are still in memory in the event of the server running out of disk space. All .jrs files are 1 MB.
A .chk file is used to identify which log files have been committed to the database. The size of .chk file varies from 2-3 KB.

The ESE takes the following steps to write information into database files:

The ESE writes a message into memory RAM when it arrives at the server.
At the same time that information is written to RAM, it's written into the current .log file. All current log files are named E00.log. The information is written in a sequential format until the log file is full. When the log file is full, it will be renamed.
Once it has been committed to the log file, the information is written to the .edb file.
The checkpoint file is updated to indicate that the transaction log that has been committed to the database.

ESP (Encapsulating Security Payload)

Ethernet

One of the major families of network architectures. The structure of all Ethernet networks is based on the bus topology. Most Ethernet networks use baseband signaling and CSMA/CD as a media access method.

Event ID

The identification for the event that displays in the Event Detail window in the Event Viewer.

Event log

Any of three log files in which Windows records monitored events such as errors, warnings, and the success or failure of tasks. Event logs include the system, security, and application logs. You can view these logs in the Event Viewer.

Event Viewer

An administration tool that provides information about such events as errors, warnings, and the success or failure of tasks.

Everyone

A special group or identity that includes all users and can be used to assign permissions that all users in a domain hold in common, including guests and users from other domains.

Exchange 2007 Management Console

The Exchange 2007 Management Console is a graphic interface used to manage an Exchange environment. It has been simplified from previous versions of Exchange so it now focuses only on the most commonly executed tasks. Additional tasks that could traditionally only be performed in REGEDIT or ADSIEDIT were also added to the Exchange Management Console to improve ease of use.

In Exchange 2003, the information shown in the tree-pane was dependent on the configuration of your Exchange Server. This pane is now static in Exchange 2007 Management Console so no matter how many servers you have, what options have been chosen, or what has been installed, the tree-pane will always be the same.

Exchange ActiveSync

Exchange ActiveSync is a protocol used by Internet-enabled mobile devices to send and retrieve Exchange data.

Exchange Management Console

The Exchange Management Console is the graphical administration tool. It is comprised of a three-paned view that includes a tree view, results, and an actions pane. It cannot perform many of the administrative tasks that can be performed in the Exchange Management Shell.

Exchange Management PowerShell

The Exchange 2007 Management Shell environment allows administrators to perform all of their tasks from a command line environment, thus making it easier to automate tasks. The PowerShell must be installed before Exchange 2007 is fully installed, then extensions are installed to the PowerShell during Exchange 2007 installation to create the Exchange 2007 PowerShell environment. The PowerShell uses with verb/noun-based syntax and is the primary platform for all administration; the graphical interface is simply running atop of the command shell.

Exchange Management Shell

Exchange PowerShell

Microsoft Exchange Management Shell (Windows PowerShell) is a command line environment designed for automating administration and maintenance. The Exchange Management Shell is the primary management interface of 2007.

Exchange storage group

A Microsoft Exchange storage group is a collection of Exchange stores (databases). A Recovery Storage Group (RSG) is a special storage group used for recovering Mailbox stores.

Executive Services

The central component of Windows network architecture. It includes the managers and device drivers that run in kernel mode.

Extended Industry Standard Architecture (EISA)

A 32-bit I/O bus slot providing compatibility with 386 through Pentium machines. EISA buses:

Have a maximum throughput rate of 33 MB/s.
Offer bus mastering which is a mini-processor on the expansion card. The mini-processor assumes the task from the CPU of transferring data to and from memory.
Offer a second row of pins to a standard ISA bus.
Provide backward compatibility with ISA cards.
Allow EISA cards to take advantage of both rows of pins (the 32-bit data path) to improve transfer rates and increase addressable memory.
Allow for automatic configuration of system resources (addresses, DMA channels and IRQs).
Support sharing of system resources.
Allow multiple EISA cards to share the same interrupt.
EISA supports multiprocessing by allowing more than one CPU to share the bus.
Are usually black, though they are sometimes white.

Extended partition

A partition you create from free space on a hard disk and can be subdivided into logical drives. You can have only one extended partition on a single hard disk.

Extensible Authentication Protocol (EAP)

Extensible Authentication Protocol over LAN (EAPoL)

The Extensible Authentication Protocol over LAN is used for authentication of 802.1X port access control over either wired or wireless LANs.

Extensible Storage Engine (ESE)

An .edb file is located in the actual database itself. All of a user's messages, folders, public folders, contacts, appointment information, etc. is all stored on the .edb file. An .edb file size can exceed multiple GB.
A .log file is an ESE transaction log file. All .log files are 1 MB.
A .jrs file is a reserve log file which is used to commit any transactions that are still in memory in the event of the server running out of disk space. All .jrs files are 1 MB.
A .chk file is used to identify which log files have been committed to the database. The size of .chk file varies from 2-3 KB.

The ESE takes the following steps to write information into database files:

The ESE writes a message into memory RAM when it arrives at the server.
At the same time that information is written to RAM, it's written into the current .log file. All current log files are named E00.log. The information is written in a sequential format until the log file is full. When the log file is full, it will be renamed.
Once it has been committed to the log file, the information is written to the .edb file.
The checkpoint file is updated to indicate that the transaction log that has been committed to the database.

Exterior Gateway Protocol (EGP)

Exterior Gateway Protocol (EGP) is a routing protocol that exchanges routing information between autonomous systems. BGP is the most common EGP protocol.

External BGP (EBGP)

External BGP (EBGP) is used by BGP to route information between autonomous systems.

External relay

Accepted domains identify the domains for which the organization is solely responsible and the SMTP domains from which the server will accept messages. There are three types of accepted domains in Exchange 2007:

Authoritative is the domain over which the Exchange server has sole responsibility. In a typical environment, the organization will have an e-mail domain of "company.com" which is hosted by the company's e-mail server. If another e-mail system or domain exists in the environment, internal and external relays are employed.
An internal relay is an e-mail domain that is hosted by another Active Directory Forest within the Exchange organization. This system uses different e-mail addresses, but all incoming mail goes through the Exchange organization.
An external relay accepts e-mail for an external organization and then delivers it to an external entity such as the Internet via the Edge Transport server.

Extranet

An extranet is a division of a private network that is accessible to a limited number of external users, such as business partners, suppliers, and certain customers.