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Company Network Requirements

Microsoft Online Services is available to your company over your Internet connection. It may replace applications that operated within your company network. The traffic that previously was confined to your network will now travel between your company and the Internet. You must ensure that your company's connection to the Internet is configured correctly and that it has enough capacity to handle the network traffic.

Network Configuration

If your company protects your connection to the Internet with a firewall or proxy server, refer to the table below to see the ports used by Microsoft Online Services.

The computers on your network must be able to successfully perform standard Internet DNS lookups. If your computers can reach standard Internet sites, your network meets this requirement.

Note:
If your company uses an authentication proxy, you must add "microsoftonline.com" to your proxy's exceptions list in order to work with Microsoft Online Services.

Bandwidth Considerations

Microsoft Online Services currently offers three online services: Microsoft Exchange Online, SharePoint Online, and Office Live Meeting. Each of the services has its own bandwidth requirements.

There are many variables to consider when estimating network traffic. Some of these variables are:

• The services that your company has subscribed to
  
  
• The number of client computers in use at one time
  
  
• The type of task each client computer is performing
  
  
• The performance of your Internet browser software
  
  
• The capacity of the network connections and network segments associated with each client computer
  
  
• Your company's network topology and the capacity of the various pieces of network hardware
  
  

The following sections provide guidelines for estimating the bandwidth usage of each service. Detailed specifications are beyond the scope of this topic. For more detailed information about estimating the network traffic for each online service, see the links to other documentation in each of the following sections.

Exchange Online

The information in this section will help you begin to estimate the network bandwidth that your company will need to run Exchange Online.

The estimates provided in this section are based on the following assumptions:

• The average message size is 50 kilobytes (KB).
  
  
• Every message delivered is read.
  
  
• Half of all incoming mail is deleted.
  
  
• OWA clients log on and log off two times per day.
  
  

Note:
Office Outlook 2007 log on and log off costs were not evaluated because company e-mail users generally stay logged on for days at a time.

The following table lists the message usage for light, medium, heavy, and very heavy e-mail users. This information will be used later in this section to estimate network traffic.

The following table shows the amount of network traffic generated by each type of user in each e-mail client. All values are in kilobytes (KB) per day per user.

To apply this information to your company, consider the following examples. Each example assumes that the users are in the same time zone and that they perform most of their work during the same eight hours of the day.

• Example: If your company has 100 heavy Office Outlook 2007 users, here's how to calculate the average network traffic, measured in bytes per second.
  
  Network bytes/sec = (100 heavy users × (5,200 KB/user ÷ day)) ÷ (8 hr/day × 3600 sec/hr) = 18.5 KB/sec
  
  Assuming a daily peak of twice the average usage, your network connection would need to support approximately 37 KB/sec.
  
  
• Example: If your company has 100 medium OWA users, here's how to calculate the average network traffic, measured in bytes per second.
  
  Network bytes/sec = (100 medium users × (12,220 KB/user ÷ day)) ÷ (8 hr/day × 3600 sec/hr) = 42.4 KB/sec
  
  Assuming a daily peak of twice the average usage, your network connection would need to support approximately 84.9 KB/sec.
  
  

For more capacity planning information, see White Paper: Outlook Anywhere Scalability with Outlook 2007, Outlook 2003, and Exchange 2007.

SharePoint Online

The information provided in this section will help you begin to estimate the network bandwidth that your company will require to run SharePoint Online. This information is based on the following assumptions:

• An average interaction (page load) transfers approximately 100 KB.
  
  
• A typical user generates about 36 interactions (page loads) per hour.
  
  
• About 10 percent of a company's users will be active at the same time.
  
  

To show how to apply this information to your company, consider the following example. This example assumes that all of the users are in the same time zone and that they perform most of their work during the same eight hours of the day.

• Example: If your company has 1000 SharePoint Online users, here's how to calculate the average network traffic for each user, measured in bytes per second.
  
  Network bits per second = (100,000 bytes/load × 8 bits/byte × 36 loads/hr) ÷ 3600 seconds/hr = 8000 bits per second
  
  A company with 1000 users would have approximately 100 active users at any one time. Those 100 users would require approximately 800 x 8000 bits per second or 800 kilobits per second of available network bandwidth. Assuming a daily peak of twice the average usage, your network connection would need to provide approximately 1.6 megabits per second of network bandwidth.
  
  

In addition to the bandwidth requirement, SharePoint Online requires a network latency of no greater than 250 milliseconds.

For more detailed information about capacity planning for SharePoint Online, see Plan for bandwidth requirements.

Office Live Meeting

The information in this section will help you begin to estimate the network bandwidth that your company will need to run Office Live Meeting.

Office Live Meeting offers two different clients:

• Office Live Meeting Client (Windows-based client)
  
  
• Office Live Meeting Web Access (Web-based client)
  
  

The following table lists the bandwidth requirements for each of the functions available in the Office Live Meeting Client. All values are in kilobytes per second (KBps) for one user.

Note:
The bandwidth requirements listed are cumulative. For example, if you want to use voice, video, and Office RoundTable, the minimum bandwidth would be 50 + 50 + 100 = 200 KBps per user.

Office Live Meeting Web Access (MWA) is an alternative for users of the Office Live Meeting service who cannot install or run the Windows-based meeting client. MWA is an applet-based program that runs on any of the Java runtime environments specified in the Microsoft Office Live Meeting (2007 version) system requirements. MWA does not require installation of any files. However, initiating application sharing on Macintosh computers using MWA does require installation of an application-sharing component.

The minimum bandwidth recommendation for the MWA client is 56 KBps.

For more information about Live Meeting network utilization, see Technical Considerations for Microsoft Office Live Meeting Service Deployment.

Migration and Directory Synchronization Tools

The Migration Tools and Directory Synchronization tool are installed on computers on your company network, behind a firewall or proxy server. These computers should have direct access to your company's domain controllers and e-mail servers. They will connect to Microsoft Online Services through your company's firewall or proxy server.

Your company may use the Migration Tools to migrate mailbox content from your existing e-mail environment to Exchange Online. Migration will impact your network only when actually performing the migrations. When migrating large numbers of mailboxes, you should perform the migrations in small batches to minimize the impact to your network bandwidth. The Migration Tools console reports the total size of the mailboxes selected to be migrated. When you know the number and the size of your existing mailboxes, you can determine the impact on your e-mail servers and your network bandwidth. For more information about e-mail migration, see About E-Mail Migration.

If your company establishes directory synchronization using the Directory Synchronization tool, there will be a one-time impact on your network when all of your company's user accounts and e-mail enabled contacts and groups are synchronized for the first time. This operation will use the available network bandwidth for the duration of the synchronization. You can expect the first synchronization of 500 objects to take approximately 70 minutes. The first synchronization of 5,000 objects will take approximately 120 minutes. The actual time will be determined by the available bandwidth of your organization's Internet connection.

After the first synchronization, the Directory Synchronization tool will synchronize changes every three hours. The impact of this traffic is usually very small. For more information about directory synchronization, see About Directory Synchronization.