Communications Express provides an integrated web-based communications and collaboration client. Communications Express is a common part of Messaging Server and Calendar Server, providing end users with a web interface to their calendar information and mail, as well as an address book.
This chapter contains the following sections:
Communications Express depends upon the following Sun Java System component products:
Access Manager (if you are using Sun Java System LDAP Schema Version 2)
You install Communications Express as a front-end server (in a multi-tier environment). You must install the complete set of Messaging Server packages on the same host that Communications Express is running on. Also, both Communications Express and Messenger Express must run on the same IP address. The Messaging Server packages can then be configured to run as Messenger Express or as MEM, which connects to a back-end store running Messenger Express.
In addition, you can configure Communications Express to have the Address Book on the front-end machine store its data either in the LDAP directory infrastructure or on an LDAP server other than the Communications Express machine. See the Sun Java System Communications Express 6 2005Q4 Administration Guide for more information.
Communications Express communicates with Calendar Server through the Calendar Server HTTP service, the mshttpd daemons for Messaging Server, and the LDAP service for address book. The cshttpd daemon can be local or remote, the mshttpd daemon can be either the local Webmail server or MEM, and the LDAP service can be either local or remote.
When using a load balancer or port director type device, make sure to utilize “sticky” (persistent) connections such that users are continually routed to the same front-end server for the duration of their session.
Communication between mail and calendar is established using Access Manager or Messaging Server single sign-on mechanism.
Both calendar and mail applications share the same address book.
The Address Book Store provides horizontal scalability. See the Sun Java System Communications Express 6 2005Q4 Administration Guide for more information.
Communications Express supports virtual domains.
The Calendar and Address Book client modules are deployed as a single web application in a web container, which can be either Sun Java Systems Web Server or Sun Java Systems Application Server. The mail module is rendered by Messenger Express. Messenger Express is the standalone web-based mail application that uses the HTTP service of the Messaging Server.
Messenger Express or MEM should be deployed on the same system where Communications Express is deployed.
Figure 25–1 shows the Communications Express software architecture.
Communications Express consists of the following modules:
Calendar. The presentation layer of the Calendar module is based on JavaServer PagesTM. These JavaServer Pages pages can be customized to suit the requirements of the client. The data layer accesses a Java API for Calendar (JCAPI) to enable exchange of data with Calendar Server over HTTP-based protocol.