Tài liệu Module 13: Real-Time Collaboration in Exchange 2000 pptx

Use/Design Instant Messaging Instant Messaging Chat Server Data Conferencing Data Conferencing Primary Use Instant Messaging Instant Messaging Conferencing Data Conferencing Meeting Styl

Exchange 2000

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Project Lead: David Phillips

Instructional Designers: Lance Morrison (Wasser), Janet Sheperdigian, Steve Thues

Lead Program Manager: Mark Adcock

Program Manager: Lyle Curry, Scott Hay, Janice Howd, Steve Schwartz (Implement.Com),

Bill Wade (Wadeware LLC)

Graphic Artist: Kimberly Jackson, Andrea Heuston (Artitudes Layout and Design)

Editing Manager: Lynette Skinner

Editor: Elizabeth Reese (Write Stuff)

Copy Editor: Ed Casper (S&T Consulting), Carolyn Emory (S&T Consulting), Patricia Neff

(S&T Consulting), Noelle Robertson (S&T Consulting)

Online Program Manager: Debbi Conger

Online Publications Manager: Arlo Emerson (Aquent Partners)

Online Support: Eric Brandt

Multimedia Developer: Kelly Renner (Entex)

Compact Disc Testing: Data Dimensions, Inc

Production Support: Ed Casper (S&T Consulting)

Manufacturing Manager: Bo Galford

Manufacturing Support: Rick Terek

Lead Product Manager, Development Services:

Lead Product Manager: David Bramble

Group Product Manager: Robert Stewart

This module provides students with the information necessary to differentiate between the three different real-time collaboration solutions, choose which has the best functions for a particular purpose, and gain the experience needed to

install and use real-time collaboration

At the end of this module, students will be able to:

„#Describe the advantages and limitations of each of the three real-time collaboration solutions

„#Describe the Instant Messaging components

„#Install and configure Instant Messaging

„#Describe the functions of the Chat Services

„#Describe the features and components of Microsoft® Exchange 2000 Data Conferencing Services

„#Explain the differences between conferencing under Microsoft Exchange Server version 5.5 and under Exchange 2000

„#Describe the Data Conferencing architecture

„#Describe the ways Data Conferencing is dependent upon Exchange 2000

„#Configure Data Conferencing

„#Use System Monitor to monitor Data Conferencing

This section provides you with the required materials and preparation tasks that are needed to teach this module

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To teach this module, you need the following materials:

• Microsoft PowerPoint® file 1569A_13.ppt

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To prepare for this module, you should:

„#Read all the materials for this module

„#Complete the labs

Use the following strategy to present this module:

„#Comparing Collaboration Components The module starts with an overview of the three real-time collaboration components The comparison slide is a good place to describe the different purposes of each component

„#Instant Messaging Components This section describes the overall architecture of Instant Messaging and then goes into greater detail about the server and client, and their relationship to Windows 2000 The important points are the improvements in the

architecture over the design of Exchange Server 5.5

„#Configuring Instant Messaging This topic describes the features that need to be configured and how to do it

„#Monitoring Instant Messaging This topic describes important considerations for administrators to monitor

to ensure optimum performance It discusses only tools that have already been introduced

„#Instant Messaging Best Practices This is a list of the best practices for configuring Instant Messaging at the time the course was written Bear in mind that the product was still in beta

so these practices may change with the released version

„#Chat Services There is only one slide about this topic It is not considered a major feature, and you can cover it quickly

„#Introduction to Exchange Data Conferencing This topic describes the various features of data conferencing The comparison between conferencing under Exchange Server 5.5 and Exchange 2000 are the most important points of the section

„#Exchange 2000 Data Conferencing Architecture The important point to emphasize in the architecture section is the dependence of data conferencing on services provided by Windows 2000

„#Configuring Exchange Data Conferencing This topic describes the tools used to configure data conferencing and how

to do it

„#Lab A: Configuring and Using Instant Messaging This is a short, fun lab in which the students can send messages to each other If you want to break up the long lecture, this lab can easily be performed at the end of the Instant Messaging topic

„#Lab B: Creating and Using Exchange 2000 Data Conferencing This lab is at the end because it is optional and you can expect some students to leave early This way, they will hear the lecture even if they miss the lab The students who perform it usually enjoy setting up and using their cameras to communicate with each other through NetMeeting Even if they

do not have cameras, students can configure their servers and collaborate using application sharing based on the last exercise in the lab

At the end of this module, you will be able to:

„#Choose the appropriate collaboration component to use for a given situation

„#Describe the function and configuration of Instant Messaging Services

„#Describe the function and configuration of Chat Services

„#Describe the function and configuration of Data Conferencing Services

Use/Design Instant

Messaging

Instant Messaging Chat Server

Data Conferencing

Data Conferencing Primary Use Instant

Messaging

Instant Messaging

Conferencing

Data Conferencing

Meeting Style Closed Open Forum Invitation Only

Meeting Structure

Meeting Structure

Hoc

Hoc

Immediate/Ad-Ad-Hoc/Semi Structured

Ad-Hoc/Semi Structured

Organized

Client Type Vendor-Specific Standards-Based T.120 Standards

Client Facilities

Client Facilities

Primary Deployment

Primary Deployment

Corporate Service Provider Corporate

Instant Messaging, Chat, and Data Conference all have unique features suited to different, specific situations

Exchange Instant Messenger

File Tools Help

Contacts Currently Online sakhtar@im-2k (Online) dcampbell@im-2k (Online) sgode@im-2k (Online) Contacts Not Online seanch@im-2k (Offline) kbowen@im-2k (Offline) scottfal@im-2k (Offline) linleste@im-2k (Offline) amyjon@im-2k (Offline) kjordan@im-2k (Offline)

Online

Instant messaging allows you to send messages that require an immediate response from the receiver You can also see when other people are online, out

of the office, or not receiving calls (this is called presence information) For

example, members of a virtual team that are collaborating with one another to produce a single product may need the urgency of information delivered by Instant Messaging; or in the Internet space, friends may want to chat with one another through a live discussion thread, without the overhead of composing and sending e-mail

The major difference between e-mail and instant messages is that instant messages are not kept in the Exchange 2000 store; after a message has disappeared from the screen, it is gone forever

The Instant Messaging client is an iteration of the Microsoft MSN™ Messenger product You can start the client automatically as soon as you log on and keep it open in the corner of your screen all day

When you are online, this fact is sent as a status notification to the Instant Messaging server that passes the information to other members of the team or interested parties Likewise, a user logging on to the network can quickly find out who else is online and able to communicate

Instant Messaging is designed as a way to track the presence of each member of

an individual team For example, as an Instant Messaging user, you may have listed in your client ten other team members, their manager, three contacts in other companies, and a few friends on the Internet

There are seven modifiable presence settings that you can change as appropriate

on your Instant Messaging client:

„#Idle When there has been no activity at your keyboard for a given time, the

screen saver trigger is activated and your status is set to idle It switches back to online when you touch a key

„#Offline You are not logged on to the Instant Messaging server

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An Instant Messaging domain is a logical collection of Instant Messaging users and servers represented by a virtual server called an Instant Messaging router Instant Messaging routers can have Domain Name System (DNS) hostnames that are visible to external (Internet) users

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Each Instant Messaging domain must contain at least one home server, which is

a virtual server that hosts Instant Messaging user accounts Home servers also store status information for users assigned to that particular server

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An Instant Messaging router receives instant messages, determines their destination home server, and forwards the messages to user accounts on the home server Because the Instant Messaging domain name represents the host name of the router, users do not need to know the individual home server names because the router obtains the server names from Active Directory, and routes users accordingly

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All Instant Messaging communication takes place over HTTP (Hypertext Transfer Protocol) The message format is XML (Extensible Markup Language)

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Server Admin.

(MMC)

Server Admin.

(MMC)

Server Application Layer

Server Application Layer

RVP MSN AOL

Active Directory

Active Directory

Internet Information Services

Internet Information Services

DNS

The Instant Messaging architecture includes components located both at the client and the server The Instant Messaging Server and Client also rely on Windows 2000 to provide services, such as Domain Name System (DNS) and Security

Server Admin.

(MMC)

Server Admin.

(MMC)

Server Application Layer

Server Application Layer

RVP MSN AOL

Active Directory

Active Directory

Internet Information Services

Internet Information Services

DNS

The Instant Messaging server itself runs as part of the Windows 2000 Internet Information Services (IIS) process (Inetinfo.exe) and is implemented as an Isapi.dll

All Instant Messaging communication between clients and servers takes place

by using the RVP protocol (also known as the rendezvous protocol) RVP is an extended subset of Hypertext Transfer Protocol - Distributed Authoring and Versioning (HTTP-DAV), which is an extension to HTTP 1.1

Developers can use RVP within their applications to access the Instant Messaging presence data for other uses

You can choose whether to enable Instant Messaging with entities outside of the corporate network, such as other Exchange 2000 installations maintained by business partners, suppliers, or customers Some organizations may need intranet-only messaging In these cases, all of the Instant Messaging infrastructure is located behind the firewall, and is never exposed to the Internet If your company needs connectivity with the Internet, you should protect your internal Instant Messaging network with firewalls in both the inbound and outbound directions

The Firewall Topology Module (FTM) retains information about each Instant Messaging Server, whether it is inside or outside of the firewall It also maintains information about how to get through the firewall The FTM contains data that tells whether a given source Internet Protocol (IP) can connect to a given destination IP, and whether a proxy server is required

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The locator dispatches notifications to the correct home server when the messages are passed through the bridgehead servers

Server Admin.

(MMC)

Server Admin.

(MMC)

Server Application Layer

Server Application Layer

RVP MSN AOL

Active Directory

Active Directory

Internet Information Services

Internet Information Services

DNS

You use the Instant Messaging Client to log on to the Instant Messaging server, and communicate with other Instant Messaging users It includes the following components:

„#Instant Messaging Client User Interface (UI)

Users can use the IM Client to log on to an Instant Messaging server, configure security, and configure support for other providers

„#Providers

The MSN and AOL providers allow the Exchange Instant Messaging client

to communicate with contacts on MSN and AOL

„#RVP Support

The Instant Messaging client uses the RVP Protocol Support provided by Windows 2000 to communicate with Exchange 2000 Instant Messaging Servers

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All Instant Messaging users are identified to Instant Messaging Service by unique Instant Messaging URLs that follow the usual conventions for Web URLs The RVP used by the Instant Messaging Service refers to all entities by their Instant Messaging URLs Each user has two Instant Messaging URLs, a home server URL and a domain URL However, when logging on to Instant Messaging, or adding contacts, users can use a simplified address based on an SMTP address called the Instant Messaging User Address

This HTTP address points to the Instant Messaging home server where the user

is stored For example, the user Kim at Northwind Traders who is an Instant Messaging user on the Vancouver server in an Exchange organization with an

IM_Domain equal to im.nwtraders.msft would have the following home server

URL:

• http://im.vancouver.nwtraders.msft/instmsg/local/im.nwtraders.msft/instmsg/aliases/kim

User_name@IM_Domain

For example, the user Kim at Northwind Traders would have the Instant Messaging address kim@im.nwtraders.com

It is possible to configure the Instant Messaging domain to be the same

as the SMTP domain This will be covered later in the module

Users who want to use Instant Messaging need to install the following software:

1 Internet Explorer version 5.0, which can be downloaded at no charge from http://www.microsoft.com/windows/ie/

2 Microsoft Proxy Client version 2.0 (if you communicate outside of your Exchange organization)

3 Exchange Instant Messenger, which is available from the

\Instmsg\I386\Client directory on the Exchange 2000 compact disc

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Server Admin.

(MMC)

Server Admin.

(MMC)

Server Application Layer

Server Application Layer

RVP MSN AOL

Active Directory

Active Directory

Internet Information Services

Internet Information Services

DNS

Exchange Instant Messaging is dependent on Windows 2000 for several important functions provided by Active Directory, Internet Information Services (IIS) version 5.0, and DNS Records

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Instant Messaging users are created by using the Active Directory Users and Computers MMC snap-in It is not necessary to have a separate user account for Instant Messaging All users in Active Directory can use Instant Messaging Active Directory also provides the security for connecting to Instant Messaging servers by requiring users to provide their Active Directory user ID and

password in order to authenticate in Active Directory, before logging on to their Instant Messaging server

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All Instant Messaging servers must have DNS A records created so that Instant Messaging clients and servers can resolve fully qualified domain names (FQDN) to IP addresses in order to make connections

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Instant Messaging clients connect to the IIS service and the instmsg alias when

logging on to Instant Messaging

Status Information Client Logon Status Information Client Logon

When a user logs on to Instant Messaging, they provide their Instant Messaging

user ID in the form of alias@im_domain In addition, the user must provide an

Active Directory user name and password, to be authenticated on their home

server The im_domain portion of the Instant Messaging address is the FQDN

of the Instant Messaging router The following steps illustrate the client logon process

1 Client logs on as alias@im_domain and connects to the Instant Messaging router

2 The Instant Messaging router queries Active Directory for the users Instant Messaging home server

3 The Instant Messaging router returns the home server URL address to the client

4 The Instant Messaging client uses the home server URL address to connect to their Instant Messaging home server

5 The Instant Messaging home server validates the users’ Active Directory user name and password

If there is only one Instant Messaging home server, the im_domain

is the FQDN of the home server If there are two or more home servers, the

im_domain must be the FQDN of the Instant Messaging router

IM user status information is updated in the Node Database of their home server Other Instant Messaging users that have this user as a contact are notified of status changes by the user’s home server

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Instant Messaging users can add contacts to their client After a contact is added, the Instant Messaging client will obtain status information from the

contact’s home servers This is known as a subscription Contacts’

subscriptions are stored in the Node Database on the home server, and also in the client registry under the following key:

HKEY_CURRENT_USER\Software\Microsoft\Exchange\messenger\profiles\h

ttp://im_domain/instmsg/aliases/alias\Contacts

Private Network Internet

IM Client Outside Firewall

IM Client Outside Firewall

Proxy Sever Firewall

Proxy Sever Firewall

IM Client Inside Firewall

IM Client Inside Firewall

Inside Firewall Outside Firewall Inside Firewall Outside Firewall

In addition to the client logon, authentication, and status operations described earlier, IM server operations also include redirecting clients to home servers and proxy operations for clients outside a network firewall

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You can deploy Exchange 2000 in a front-end/back-end configuration where the protocols and store can be split onto different servers Instant Messaging servers operate with a similar concept

A bank of Instant Messaging routing servers can be used as the primary point of contact, and these redirect clients to the home server for the Instant Messaging user The bridgehead server configuration allows for one or more front-end servers to provide a unified view of the Instant Messaging topology

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An Instant Messaging routing server will return the appropriate URL to the requesting client to make the requesting client’s connection based on the requestor’s IP address and the configuration of the FTM If the IP address is inside your firewall, the home server URL is returned; if it is from outside the firewall, the Instant Messaging domain URL is returned and all client

communications will be sent through an Instant Messaging routing server In this configuration, Instant Messaging clients outside the firewall only connect

to the Instant Messaging router The Instant Messaging router proxies the client operations to the Instant Messaging home server on behalf of the Instant Messaging client outside of the firewall

To create a virtual server as an Instant Messaging router, give it the same DNS

name as the FQDN of the server This will be the same as the IM_Domain for the company For example, if the IM_Domain is im.nwtraders.msft, then the

DNS name of the Instant Messaging router would be im.nwtraders.msft The

Instant Messaging router is also configured not to host Instant Messaging user

User

Instant MessagingAddress URL

Instant MessagingHome Server URL

Instant Messaging Domain

Instant Messaging

You enable individual users for Instant Messaging through the Active Directory Users and Computers snap-in When enabling a user, you choose which Instant Messaging home server in the Exchange organization will host the user This creates two URLs: an Instant Messaging Address URL which is specific to your Instant Messaging domain and an Instant Messaging home server URL which is specific to your home server

Unified Namespace

DNS – NWTRADERS.MSFT

_rvp SRV im.nwtraders.msft Im.nwtradersmsft A 192.168.1.200

The Instant Messaging domain of a user’s Instant Messaging address should be based on the SMTP hostname of the user's e-mail address For example, a user whose e-mail address is kim@nwtraders.msft should have an Instant Messaging domain of im.nwtraders.msft

Using the prefix “im” to denote an Instant Messaging domain allows external users to easily determine an Instant Messaging address from an e-mail address For example, users, whose e-mail addresses end with @nwtraders.msft, should have the Instant Messaging domain im.nwtraders.msft Similarly, users, whose e-mail addresses end with @jp.nwtraders.msft, should have the Instant

Messaging domain im.jp.nwtraders.msft

The Instant Messaging domain should be identical to the hostname of the Instant Messaging router

Instant Messaging users’ addresses can be simplified by using DNS SRV (service) resource records to create a unified namespace, so that a users Instant Message address is the same as their SMTP address

users You are considered online for this purpose if your client is actively

running on the desktop (the client is logged in to the Instant Messaging system)

A typical corporate user is probably “logged in” to the system during the workday Some users – the ones that leave their clients running all the time (the client marks them as “idle” when they are not at work) – are “logged in” to the Instant Messaging system continuously, 24 hours a day

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In typical corporate settings, a large fraction, 80 percent for example, of all users are expected to be concurrently online at peak, if the users are usually at their computers In ISP-type scenarios, a much smaller fraction, five to ten percent of all users, are expected to be concurrently online at any given time Therefore, a company with 30,000 users, who all have accounts and are mostly

at their desktops during the workday, might need three home servers, since almost all 30,000 users might be logged in at peak An ISP with 1,000,000 users and a five percent peak online rate would need five home servers, because the load would peak at 50,000 concurrently online users

„#If you plan to connect your Instant Messaging network to the Internet:

• Install all home servers and Instant Messaging routers on computers protected by a firewall

• Do not allow direct Internet connections to home servers Instead, use one or more Instant Messaging routers as “front-end” servers to handle Internet traffic This protects user accounts and data on the home servers and avoids exposing their hostnames to the Internet

• Direct all outgoing presence information requests and instant messages through an HTTP proxy server

• Direct all incoming presence information requests and instant messages through Transmission Control Protocol (TCP) port 80 on a reverse proxy This ensures the privacy of your Instant Messaging router IP addresses

„#Use a consistent and intuitive naming convention for your Instant Messaging servers, domains, and addresses

„#Use DNS SRV record so that you have a unified namespace with your SMTP address

„#If you are deploying Instant Messaging for the first time, consider a phased rollout Start with one group in your Exchange organization, and then add other groups over time

Chat Service that will allow users to whisper messages to one another, although

this is normally the exception rather than the rule

Chat Service was first introduced into the Microsoft Exchange product line with Exchange Server 5.5 Some companies are using Chat Service as a mechanism for holding company meetings for employees who are spread over long distances This gives the employees the opportunity to have a structured question-and-answer session rather than all of the participants trying to ask a question at once Other companies are using Chat Service as a vehicle for brainstorming sessions, where anyone can interject their thoughts without having to be explicitly invited to a conference call

The Exchange 2000 Chat Service is fairly simple in that it allows a fully functional chat network to be up and running within a matter of minutes You can install Chat Service on Exchange 2000 Server by using the standard installation program The administrator needs only to define some channels (or rooms as they are known in the client) to which the users can connect

Of course, although simple in nature, Chat Service can be configured with some

advanced options, such as bans that restrict certain clients from accessing a

channel at all or during certain times of the day Each channel can also be configured with a Platform for Internet Content Selection (PICS) rating so that users can have some forewarning regarding the content and language used within the room

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By default, each channel can accommodate up to 5000 users, although you can adjust this setting as required Due to the nature of the Chat Service protocol, an entire channel has to be located on a single Chat Server However,

Exchange 2000 Chat Service is highly scalable and are appropriate for deployment both in large companies and Internet service providers

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As the Chat protocol is an open industry standard, many types of clients from different vendors can connect to an Exchange 2000 Chat Server, such as Microsoft Comic Chat version 2.0 Users generally create their own local profiles, defining their real names, aliases, and other information Users must also specify the name of a Chat Server to connect to Internally, a client will connect to port 6667 (default) on the Chat Server From here, a client can list the rooms that have been created and, with the necessary access permissions, create new rooms

To make all of this possible, several server-side components in Exchange 2000 perform conference management and session coordination You can schedule online meetings and book virtual resources through integration with Microsoft Outlook® 2000 The client uses the T.120 protocol, which is integrated into products, such as Microsoft NetMeeting, to join the conference and communicate with the conferencing server

The server running Exchange 2000 acts as a full T.120 data conferencing server and is capable of supporting IP multicast audio and video streams

A user can share a program running on one computer with other participants in the conference Participants can review the same data or information and see the actions as the person sharing the application works on the program (for

example, editing content or scrolling through information) Participants can share Windows-based applications transparently without any special knowledge

of the application capabilities

The person sharing the application can choose to collaborate with other conference participants, and they can take turns editing or controlling the application Only the person sharing the program needs to have the application installed on their computer

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You can use the shared clipboard to exchange its contents with other participants in a conference by using familiar cut, copy, and paste operations For example, a participant can copy information from a local document and paste the contents into a shared application as part of a group collaboration

With the file transfer capability, a user can send a file in the background to one

or all of the conference participants When one user drags a file into the main window, the file is automatically sent to each person in the conference; they can then accept or decline receipt This file transfer capability is fully compliant with the T.127 standard

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Multiple users can simultaneously collaborate by using the whiteboard to review, create, and update graphic information The whiteboard is object-oriented (versus pixel-oriented), enabling participants to manipulate the contents by clicking and dragging with the mouse In addition, they can use a remote pointer or highlighting tool to point out specific contents or sections of shared pages

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A user can type text messages to share common ideas or topics with other conference participants, or record meeting notes and action items as a part of a collaborative process Also, participants in a conference can use chat to communicate in the absence of audio support A whisper feature allows a user

to have a separate, private conversation with another person during a group chat session

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IP Multicast is an extension to IP that allows for efficient group communication For Exchange 2000 Data Conferencing, IP Multicast provides Exchange 2000 with the capability to send and receive audio and video streams between conference participants Specifically, IP Multicast Audio and Video Conferencing provides the following capabilities:

„#Multiparty audio-video conferencing

„#Broadcast of participants’ audio and video clips

„#Participants receive, mix, and render all other participants’ audio and video streams

After joining a conference, the client computer’s Web browser is launched with URL connection to the conferencing server You can manipulate and configure the client application through a right-click context menu The menu provides the ability to:

„#View the details associated with a specific attendee

„#Configure the client options for the default video display scaling

„#Set the video window’s magnification level to 50, 75, 100, 150, or 200 percent

„#Toggle between docked and undocked windows This allows you to move windows around the interface

„#Lock or unlock a dynamic terminal to a specific participant

„#Open the multimedia mixer to set the gain and volume

„#Display ‘about’ dialog box that allows access to the component user help

Identical Data

If you have used NetMeeting before, you are probably aware of some of the following limitations of this application:

„#Most clients do not have a scheduling facility

„#The NetMeeting paradigm works best when only a small number of people want to join a meeting, because all communications are funneled through the host workstation

„#If the host computer drops out of the call, the entire conference closes down

„#The meeting model works within an Exchange organization or purely across the Internet, but not both simultaneously

„#Nearly all companies connected to the Internet will have a firewall in place for security Although it is possible to allow T.120 sessions through a firewall, because a user’s workstation needs to host the meeting, there is too much overhead and potential security risk to configure the firewall to allow this traffic directly through to workstations

Traditional connection-oriented conferencing suffers from a number of problems:

„#User complexity Users must know the location of every user that they wish

to converse with, limiting scalability and fault-tolerance, and rendering it difficult for users to add and remove themselves from a conference

„#Wasted bandwidth A user wishing to broadcast data to n users must send data through n connections

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The total bandwidth required for multiparty conferences, in which all users are sending data, goes up exponentially (N2) as the number of parties involved increases, leading to huge scalability problems