Sametime 8.5.2 server architecture

As we have described briefly, the server architecture for Sametime 8.5.2 has changed significantly from previous versions. Prior to this version, Sametime was a single server installation and ran as an add-in task under a Domino server. It provided both instant messaging and web conferencing features combined into a single server. Although there was a license model that only installed and enabled the instant messaging features (Sametime Entry), the installer was the same if you wanted to include web conferencing functionality as well.

The new architecture still includes a Domino-based component but the Domino server is intended strictly for instant messaging and awareness. All other Sametime functionality has been re-engineered into separate server components running on top of the WAS platform. By moving all but the instant messaging and awareness services from Domino onto WebSphere, IBM has constructed an environment better suited to the needs of enterprise customers who have a high demand for services that require significant non-Domino resources such as audio, video, and web conferencing.

Additionally, the new architecture of Sametime 8.5.2 is about enhancing the client experience, dramatically improving performance, and bringing the technology in line with modern audio, video, and browser standards.

Let us begin by taking a look at the new server components and learning about their role and function.

Sametime System Console

Core to the entire Sametime multi-server architecture is the management interface which runs as a WebSphere application. It is called the Sametime System Console (SSC). The SSC actually plugs into the standard WAS 7.x menu as an additional option.

The SSC provides the configuration and management tools needed to work with all the other Sametime components, including the Domino-based Instant Messaging server. It also comes with a series of step-by-step guides called Sametime Guided Activities to walk you through the installation of each server component in the proper sequence. The SSC also has a Sametime Servers section that allows you manage the Sametime servers.

The SSC installs as an add-in to WAS and is accessed through a browser on its own dedicated port. It also uses a custom DB2 database named STSC for storage of its management information.

Sametime Community Server

Sametime Community Server is the instant messaging and presence awareness component of Sametime, which is installed as an add-in task for Domino. It must be installed on Domino versions 8.5 or 8.5.1, but it can work with earlier versions of Sametime already installed in your environment. Keep in mind, however, that pre-8.5.x clients will not benefit from many of the new features provided by your Sametime 8.5.2 servers. If your requirement is solely for instant messaging, then this is the only component you will need installed alongside Domino itself.

The Sametime Community Server "standard" install also includes the original Domino-based Meeting Center. This browser-based component has not been updated in any way from pre-8.5.x versions and is there purely for backwards compatibility and to maintain any existing scheduled meetings. There is no integration or interaction between the Domino-based Meeting Center and the Sametime 8.5.2 Meeting Center(s).

Other than being updated to run on top of a Domino 8.5 or 8.5.1 server, the actual Community Server component has changed very little and includes no significant new features from previous versions. Its browser administration interface and options remain the same. However, if you have deployed the SSC, the native Domino administration is over-ridden.

Following is a chart of the Sametime Community Server infrastructure. Note the optional management of the server by the SSC. Although the use of Domino as a directory is still supported, it is highly recommended you deploy Sametime using a Lightweight Directory Access Protocol (LDAP) directory. If you will be deploying other Sametime 8.5.2 components, then your deployment will usually require an LDAP directory to be used.

Sametime Meeting Server

The Sametime Meeting server has been completely re-engineered to bring it up to the standards of modern web conferencing solutions. It is also better aligned with IBM's Sametime Unyte online service. The new Sametime Meeting Server (versus the Domino-based Meeting Center) runs as an application under WAS. In addition, as it requires a data store to hold meeting information, it utilizes a dedicated DB2 database for managing the content of each meeting room.

The previous Sametime meeting client was entirely browser-based. To improve performance and functionality for 8.5.2, a rich meeting center client has been introduced which plugs into the Sametime Eclipse environment. A browser interface for meetings is still available but it provides a reduced set of functions.

Sametime Proxy Server

The Sametime Proxy Server re-introduces a lightweight browser-based client for Sametime, which has not been available in versions shipped since 6.5. The new browser client is designed to be lightweight and fully customizable and it is based on Ajax technology and themed using CSS. This allows it to launch quickly and be customized to match your organization's design.

The Proxy Server installs as an application under WAS, although it has no data store of its own and does not require any database connectivity. In the configuration for the Proxy Server, you direct it to a specific Community Server to supply the Sametime services. The following diagram gives a brief overview:

The Proxy Server ships with a default client designed as a JavaServer Page, which can be modified using customizable style sheets. It gives a feature-rich Sametime experience including multi-way chats, browser-based meetings, and privacy settings.

Sametime Media Manager

The Sametime Media Manager takes on the role of providing audio and video services for both the Sametime clients for peer-to-peer VoIP and video chats, and for web conferencing within the meeting rooms in the new meeting center. It is designed to provide services for multiple Meeting Servers and through them for instant meetings from the Sametime client. Installed on a WAS platform, it has no need for a data store and does not require any database connectivity.

The Media Manager is designed to provide a multi-way audio and video conferencing experience using modern codecs; however, it does not support Sametime clients in versions prior to 8.5.2. It is the audio and video "glue" that connects all the other Sametime server elements in 8.5.2.

Sametime TURN Server

In its default configuration, the Media Manager creates a SIP connection from itself to the requesting client. However, where the client is not on the same network as the Media Manager, no SIP connection can be made directly. To address this issue, which affects users outside of your firewall as well as those on different internal networks, IBM has introduced the TURN Server with Sametime 8.5.2.

The TURN server uses both TURN and STUN protocols to create a connection with the client. It routes audio and video traffic between itself and the Media Manager, allowing connections between clients across networks. The technology is sometimes referred to as a reflector and pre-8.5 versions of Sametime came with a reflector service of their own.

The TURN server is a Java program that runs in a command window on any Windows or Linux server sharing the same subnet as the Media Manager. It doesn't require WAS or any data store but runs with a separately installed IBM Java Virtual Machine (JVM).

Sametime Bandwidth Manager

The Sametime Bandwidth Manager is a new optional WAS-based component that is designed to help Sametime administrators manage the traffic generated by the Media Manager and its audio and video services. Within the Bandwidth Manager configuration, an administrator can create sites, links, and call-rate policies that define the service provided by the Media Manager. The Bandwidth Manager analyzes its rules when a new call is initiated and instructs the Media Manager on how to service that call.

Among the extremely granular levels of customization available are options for sites to have link rules that constrain the traffic between them. You can also create specific policies that specify the services available to named users or groups during peak and off-peak periods. Depending upon network load, user identity, and call participation, the Bandwidth Manager can be configured to control the bandwidth. It can do this by reducing the audio to a lower codec, reducing the video frame rate, or even denying video completely, informing the user that they should retry at a later time.

Sametime server system requirements

When planning or migrating to a Sametime environment, as with any other new software or hardware implementation, it is always prudent to plan, plan, and plan! Review the most current release notes for any changes with careful consideration of operating system, disk space requirements, and Sametime or Domino software requirements.

As with other software in the IBM Lotus family of products, the Sametime software and server components will run on different operating systems. For instance, if you have expertise in Linux, you will be happy to find that Sametime 8.5.2 runs on Linux. But if your organization or architecture requires that you run the software on Windows or AIX, then you have the ability to run Sametime on those operating systems as well. The following table provides an overview of the operating systems supported by Sametime 8.5.2 Standard and those components that will run on the specific operating systems:

Operating system	Sametime 8.5.2 Standard server component	Additional information
AIX: 5.3 TL10 POWER System i/p 64-bit or 6.1 TL3 POWER System i/p 64-bit	Classic Meeting Server; Community Server; Gateway Server; Meeting Server; Proxy Server; System Console Server	Requires 32-bit Domino
Linux: Red Hat Enterprise Linux (RHEL) 5.0 Update 4 Advanced Platform x86-32 or x86-64 or SUSE Linux Enterprise Server (SLES) 10.0 SP1 or 11.0, x86-32 or x86-64	Classic Meeting Server; Community Server; Gateway Server; TURN Server; Bandwidth Manager Server; Media Manager Server; Meeting Server; Proxy Server; System Console Server	Requires 32-bit Domino
Solaris: 10 SPARC 64-bit	Classic Meeting Server; Community Server; Gateway Server; Meeting Server; Proxy Server; System Console Server	Requires 32-bit Domino
SYSTEM i: i 5.4 IBM POWER 64-bit or i 6.1 IBM POWER 64-bit or i 7.1 IBM POWER 64-bit	Classic Meeting Server; Community Server; Gateway Server; Meeting Server; Proxy Server; System Console Server
SYSTEM z: (Sametime 8.5.1)	Community Server; Meeting Server; Proxy Server; System Console Server (Sametime 8.5.1 components)	Requires 64-bit Domino Requires 64-bit Red Hat Enterprise Linux Server 5.0 (RHEL) Advanced Platform or SUSE Linux Enterprise Server (SLES) 10.0 SP1 System z
Windows 2003 SP1 / Windows 2003 R2 Enterprise Edition x86-32 or Standard Edition x86-32	Classic Meeting Server; Community Server; TURN Server; Bandwidth Manager Server; Gateway Server; Media Manager Server; Meeting Server; Proxy Server; System Console Server	For IPv6 support, both IPv4 and IPv6 stacks must be enabled
Windows 2003 / Windows 2003 R2 Enterprise Edition x86-64 or Standard Edition x86-64	Classic Meeting Server; Community Server; TURN Server; Bandwidth Manager Server; Gateway Server; Media Manager Server; Meeting Server; Proxy Server; System Console Server	For IPv6 support, both IPv4 and IPv6 stacks must be enabled
Windows 2008 Enterprise Edition x86-32 or Standard Edition x86-32	Classic Meeting Server; Community Server; TURN Server; Bandwidth Manager Server; Gateway Server; Media Manager Server; Meeting Server; Proxy Server; System Console Server
Windows 2008 / Windows 2008 R2 Enterprise Edition x86-64 or Standard Edition x86-64	Classic Meeting Server; Community Server; TURN Server; Bandwidth Manager Server; Gateway Server; Media Manager Server; Meeting Server; Proxy Server; System Console Server	Requires 32-bit Domino

Additional information about System i requirements can be found at given website: https://www.ibm.com/support/docview.wss?rs=203&uid=swg21092193.

The following table summarizes the disk space requirements for the various Sametime 8.5.2 Standard server components. Note that these are only minimum recommendations; you should plan to allow for additional space for growth and any future server upgrades.

Operating system	Sametime 8.5.2 Standard server component	Disk space requirements
AIX	Classic Meeting Server	2 GB minimum
	Community Server	2 GB minimum
	Gateway Server; Meeting Server; Proxy Server; System Console Server	9 GB configurable space, plus 1 GB available in /tmp
Linux	Classic Meeting Server; Community Server	2 GB minimum
	TURN Server; Bandwidth Manager Server; Gateway Server; Media Manager Server; Meeting Server; Proxy Server; System Console Server	9 GB configurable space, plus 1 GB available in /tmp
Solaris	Classic Meeting Server; Community Server	2 GB minimum
	Gateway Server; Meeting Server; Proxy Server; System Console Server	9 GB configurable space, plus 1 GB available in /tmp
SYSTEM i	Classic Meeting Server; Community Server	2GB minimum for each Sametime server; minimum of 4 Disk Drives (arms)
	Gateway Server; Meeting Server; Proxy Server; System Console Server	5 GB free space (3 GB minimum) with a minimum of 6 disk drives with a caching disk controller
SYSTEM z (Sametime 8.5.1)	Community Server	10 GB minimum
	Meeting Server	2.5 GB configurable space, plus 2 GB available in /home, and 1 GB available in /tmp
	Proxy Server	9 GB configurable space, plus 1 GB available in /tmp space
	System Console Server	2.5 GB configurable space, plus 2 GB available in /home, and 1 GB available in /tmp
Windows	Classic Meeting Server, Community Server	2 GB minimum
	TURN Server; Bandwidth Manager Server; Gateway Server; Media Manager Server; Meeting Server; Proxy Server; System Console Server	8.5 GB configurable space, plus 1.5 GB available in %TEMP%

The following table gives minimum memory recommendations. It may be easier to include additional memory in a new server purchase rather than justify additional memory later. So, plan accordingly!

Operating system	Minimum memory (RAM) recommended
AIX Linux Solaris Windows	4GB physical memory (RAM) minimum per server component
SYSTEM i	6 GB physical memory (RAM) minimum for Gateway, System Console Server, Meeting Server and Proxy Server; 4 GB physical memory (RAM) minimum for Community Server and Classic Meeting Server plus 1 GB for each additional Sametime and Domino server

Finally, Sametime 8.5.2 requires DB2 database software and the integration of Sametime with an LDAP server. DB2 software is included as part of the Sametime package. Refer to the release notes for details about specific system requirements, compatibility with LDAP servers, or any other unique requirements you may have for your environment.