Client Throttling Policy In Exchange 2010…

Exchange 2010 brings a new feature to improve the performance of the server. An exchange 2010 install comes with a client throttling policy created to make sure that users are not taxing the system knowingly or unknowingly. Exchange tracks the resources used by each user and limits connection bandwidths as necessary.

You can modify the default policy or configure a new one for your network. The default policy is enough for most customers. You have to use the exchange shell to manage throttling policies with the New-ThrottlingPolicy, Get-ThrottlingPolicy, Set-ThrottlingPolicy & Remove-ThrottlingPolicy cmdlets. When you create a custom (new) throttling policy, any parameter that is not configured will inherit the values from the default policy. You can associate custom throttling policies to users or group of users using the ThrottlingPolicy parameter in the Set-Mailbox cmdlet.

Running Get-ThrottlingPolicy displays all the policies (if there are custom ones as well) on a 2010 box. If you have many policies configured and want to get the default one, run

Get-ThrottlingPolicy | Where-Object { $_.IsDefault –eq $true }

Exchange ActiveSync, IMAP, POP, Exchange Web Services, OWA & Windows Powershell are the components covered by the default throttling policy. The components are governed by four policy parameters.

• MaxConcurrency : Maximum concurrent connections a user can have against a 2010 server at a given time.
• PercentTimeInCAS : Percentage of a minute that can be spent running CAS code.
• PercentTimeInAD : Percentage of a minute that can be spent running LDAP requests.
• PercentTimeInMailboxRPC : Percentage of a minute that can be spent running mailbox RPC requests.

Check the technet article for more info.