E

electronic security policy

A statement of the methods and actions that are required to implement an information security policy.

epoxy layer

See Exchange Interprocess Communication layer (EXIPC).

ESE

See Extensible Storage Engine (ESE).

event sink

A piece of code that is activated by a defined trigger, such as the reception of a new message. The code is normally written in any COM-compatible programming language, such as Microsoft Visual Basic, Microsoft VBScript, JavaScript, C, or C++. Exchange Server 2003 supports transport, protocol, and store event sinks. Event sinks on the store can be synchronous (meaning that the code executes as the event is triggered) or asynchronous (meaning that the code executes sometime after the event).

EVS

See Exchange virtual server (EVS).

Exchange Interprocess Communication layer (EXIPC)

A queuing layer, formerly known as the epoxy layer, that allows the IIS and Store processes (Inetinfo.exe and Store.exe) to shuttle data back and forth very quickly. This layer is required to achieve the best possible performance between the protocols and database services on an Exchange server. Conventional applications require the processor to switch contexts when transferring data between two processes. Exchange Server 5.5 incorporates protocols such as NNTP, POP3, and IMAP directly into the Store.exe process, so data transfer is very efficient. The Exchange architecture separates the protocols from the database for ease of management and to support future architectures.

Exchange virtual server (EVS)

When using clustered servers, you allocate different resources (such as storage groups) to an EVS. If a node fails, you can move an EVS from the failed node to one of the remaining nodes.

EXIPC

See Exchange Interprocess Communication layer (EXIPC).

Extensible Storage Engine (ESE)

A transaction logging system that ensures data integrity and consistency in the event of a system crash or media failure. Other databases, such as the Active Directory database, also use ESE.