Glossary

Symbols

.NET Enterprise server

A server product that complies with the Microsoft .NET Enterprise Servers platform.

A

Active Directory Service Interface

A COM-based directory service that provides a unified view of differing directory structures, such as networks, e-mail systems, and groupware. This allows ADSI-compliant client applications to access a wide variety of directory services on a variety of platforms by using a single, standard set of interfaces.

Administrative client

A Windows 2000 Microsoft Management Console (MMC) snap-in that is used for remote management of Application Center clusters. The Administrative client provides the same functionality as the full server version, except that it cannot participate in cluster membership.

ADSI

The acronym for Active Directory Service Interface.

advanced synchronization

A type of on-demand synchronization that provides granular control over which applications, cluster members, and configuration settings are synchronized. Additionally, you can use advanced synchronization to synchronize content across cluster boundaries.

affinity

A network load balancing method that specifies how incoming client requests are distributed to cluster members.

Application Center

Application Center application

The logical set of content that provides a business solution. An Application Center application can be anything from a COM+ file or a registry key to an entire Web site. The application is deployed and synchronized across the entire cluster.

Application Center Events and Performance Logging

The Application Center database that is used to for cluster-wide event and performance logs, providing you with a cluster-wide view of performance trends and events.

application synchronization

A type of on-demand synchronization that synchronizes a specific application with all of the cluster members in the synchronization loop.

ASP session coherency

A load-balancing feature that ensures that client requests are sent to the correct cluster member for the duration of a session. If a client requires a server-side state (that is, all client requests for a given session must return to the same member), or if a member holds information for a specific client and the client is load-balanced to the wrong member, ASP session coherency ensures that the client requests are forwarded to the correct member.

ASP session state

The condition of and settings for a client connection to a specific cluster member.

automatic replication

automatic synchronization

A type of simultaneous update that occurs when any piece of an Application Center application is modified. There are two types of automatic synchronization: change-based synchronization and interval-based synchronization.

B

back-end adapter

C

CAPI certificate

Used for Secure Sockets Layer (SSL) and public key authentication.

change-based synchronization

A type of automatic synchronization that receives notification when synchronized content on the cluster controller changes. The changed content is updated automatically and immediately on all cluster members in the synchronization loop.

Class C affinity

A Network Load Balancing (NLB) method that directs multiple incoming client requests from the same TCP/IP Class C address range to the same cluster member.

CLB

The acronym for Component Load Balancing.

cluster

A group of independent servers working together as a unified computing resource. An Application Center cluster does not share resources; rather, it provides high availability by isolating and ignoring failed cluster members. Compare with Microsoft Windows 2000 Clustering, which provides high reliability through resource sharing and failover.

cluster controller

The cluster member that controls configuration and synchronization for the cluster.

cluster member

A server that is part of a cluster and is in the cluster's directory list. A cluster member receives content from the cluster controller and it can serve requests as part of the load-balancing loop.

cluster synchronization

A type of on-demand synchronization in which all cluster members in the synchronization loop are synchronized with the cluster controller. All applications are synchronized, except for COM+ applications.

COM

The acronym for Component Object Model, a software architecture that allows applications to be built for binary software components. COM enables software components to operate regardless of the language in which they are written, the operating system, and the location.

COM+

A set of services based on extensions of Microsoft Transaction Server (MTS) and the Component Object Model (COM) that provides improved threading and security, transaction management, object pooling, queued components, and application administration and packaging.

Component Load Balancing

A load-balancing method that allows cluster members to access COM+ components on component servers and enables the distribution of the COM+ workload among members.

controller

D

data collector

data point

DAV

The acronym for Distributed Authoring and Versioning.

DAV publishing

deferred procedure call

A software-based interrupt request, used by Windows 2000, to preempt the execution thread for a process. This interrupt is part of Windows 2000 preempted multitasking and is necessary to allow other process threads to gain access to the CPU.

deployment

The distribution of Application Center applications and/or a server image within a cluster or from a server outside of the cluster.

disabled server

disband

To terminate the association of cluster members, thereby dissolving the cluster.

DPC

The acronym for deferred procedure call.

drain time

draining

A state in which a cluster member no longer serves new requests but continues to serve existing requests. New traffic handling is disabled and no new connections to the specified member are allowed, but all active connections are maintained until the client releases the connection or a fixed time-out period expires.

E

enabled server

F

failed

A failed server is not serving content due to a problem that Health Monitor detected, such as low memory or missing pages. A failed state might take a server offline, depending on Health Monitor settings.

front-end adapter

full server version

The full server version includes all of the functionality that is required to use Application Center to manage clusters.

H

Health Monitor data collector

A data collector receives and holds Windows Management Instrumentation (WMI) data. You create and configure data points in the Health Monitor console to specify which data to collect, when, and from which server. You can group related data points into a data group.

Health Monitor rules

Health Monitor threshold

A user-defined limit, such as a percentage of available storage space. When a Health Monitor threshold is crossed, the state for the data collector changes. For example, the state changes from Normal to Warning.

high availability

Describes a device that remains operational and usable with a very low percentage of failures that interrupt services.

I

interval-based synchronization

A type of automatic synchronization where Application Center synchronizes all Application Center applications (except for COM+ applications) to ensure that the content is identical across the cluster.

L

load balancing

A technique that is used to distribute incoming client requests across cluster members. Each host can specify the relative load percentage that it will handle, or the load can be distributed across all members equally. If a member fails, the network load is redistributed dynamically across the remaining members.

load weight

A value that specifies the relative percentage of load-balanced network traffic for a cluster member to manage.

load-balanced adapter

The front-end network adapter that handles client communication.

load-balancing loop

The group of cluster members that are participating in load balancing.

M

management-traffic adapter

A back-end network adapter that handles communication within the cluster (between cluster members).

manual replication

member

member synchronization

A type of on-demand synchronization in which only the specified cluster member is synchronized with the cluster controller. This type of synchronization occurs whether or not the member is in the synchronization loop.

Microsoft .NET Enterprise Servers

The Windows 2000 platform for building and deploying distributed Web applications on the business Internet. Microsoft .NET Enterprise Servers supersedes Windows 2000 DNA.

Microsoft Application Center

Microsoft Application Center 2000

Built on the Microsoft Windows 2000 operating system, Microsoft Application Center 2000 (Application Center) is a deployment and management tool for Web applications. Application Center builds on the core Web application services provided in Windows 2000 and provides a suite of monitoring and diagnostic tools that are not available in Windows 2000.

MOF file

A text file, used by Windows Management Instrumentation (WMI), that contains definitions of the classes and instances in the Managed Object Format (MOF) language.

multicast support

An option that specifies whether Network Load Balancing (NLB) should use a multicast media access control address for cluster operations. If this option is enabled, NLB converts the cluster network address into a multicast address, if necessary. It also ensures that the cluster IP addresses resolve to this multicast address as part of the Address Resolution Protocol (ARP).

N

Network Load Balancing

A load-balancing solution that distributes incoming traffic to specified TCP and UDP ports within TCP/IP. Application Center configures and manages Network Load Balancing (NLB), keeps NLB settings consistent across the cluster, allows for configuration of key NLB settings, and integrates Application Center monitoring with NLB operations.

NLB

The acronym for Network Load Balancing.

No affinity

A load-balancing method that distributes incoming client requests across cluster members based on the client's IP address and port. Multiple requests from the same client do not need to be directed to the same member because all client requests are balanced across members without respect to the source.

O

offline

A condition where a cluster member is not participating in load balancing and does not respond to incoming clients requests sent to the cluster.

on-demand synchronization

A type of synchronization in which on demand copying of content from one cluster member to another only occurs with an administrator's interaction. There are four types of on-demand synchronization: advanced synchronization, application synchronization, cluster synchronication, and member synchronization.

online

A condition where a cluster member is participating in load balancing and is responding to client requests sent to the cluster.

P

performance history

A set of data from performance counters for a period of time.

port rules

A technique that allows you to control how TCP or UDP ports handle various types of TCP/IP traffic.

publishing

To distribute static content, such as Web pages, images, and user code.

R

replication

The underlying process of copying data within the server. When the server has completed the replication process, it synchronizes the data to other servers.

request

A signal, usually generated by a client, that asks a server for information and/or services.

request forwarder

The request forwarder is used for session coherency. It sits between the client and the application and ensures that client requests are sent to the correct cluster member. This load-balancing feature ensures that clients maintain session state. If a client has established a session with a specific member and if subsequent requests are load balanced to the wrong member, the request forwarder routes the requests to the appropriate member.

S

session state

Single affinity

A load-balancing method that directs multiple incoming client requests from the same IP address to the same cluster member.

stager

A server outside of a cluster on which an Application Center application is prepared for deployment.

sticky session

synchronization

The process of comparing and updating replicated data from one cluster member and/or cluster to another member and/or cluster. In the context of Application Center, synchronization is the replication of content and configuration settings from the cluster controller to one or more members. Synchronization ensures that all synchronized content is identical across the cluster. When you add a new cluster member, it is automatically synchronized with the controller.

T

target

A server that receives content from another server. In a cluster, the target is the controller.

threshold

W

Web Distributed Authoring and Versioning

An extension to the HTTP 1.1 standard that facilitates access to files and directories through an HTTP connection.

Web-based Administrative client

A version of the Administrative client that you can use with Microsoft Internet Explorer version 5.0 or later to perform remote Web-based administration of Application Center clusters. With the Web-based Administrative client, you can view performance, availability, synchronization status, and event logs, and view, enable, and disable monitors.

WebDAV

The acronym for Web Distributed Authoring and Versioning.

Windows DNA 2000

Windows integrated security

The Windows 2000 authentication protocol for transactions between two servers in a domain, where one or both servers are running Microsoft Windows NT 4.0 or earlier.

Windows Management Instrumentation

An operating system interface through which instrumented components can provide information and notification.

WMI

The acronym for Windows Management Instrumentation.

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