Exchange 2013 has introduced Mobile device mailbox policy which is more useful interms of managing active sync enabled users for managing passwords,specifying the minimum passwords length globally,mandatory special characters to be included and  setting up a device wipeout  after few number of failed password attempts.

The exchange active sync mailbox policies can be created via exchange administration center (EAC) or Exchange management shell (EMS).

Its better  and easier to create active sync mailbox policy via EAC and then add few more features extra by using EMS.

Below are the screenshots for creating device mailbox policy via EAC

1)Open Exchange Admin Center and click on the mobile option

2)You can see the default mailbox policy which is configured automatically during  the installation

3)Click on the add button to configure a new mailbox policy which opens up  the below screenshot

4)You can set the required parameters such as password length,number of sign-in failures which will be effected according to the policy you set globally or for few specific groups

5) Also you have few additional parameters added like password relogin after idle time out,password recycle count in as shown in the below screenshot

Once  we click on save activesync policy will be created.

After this creation to manage the active sync policy its better to use Exchange Management Shell since it has few more parameters which would be helpful and more efficient by using Set-ActiveSyncMailboxPolicy parameters

References : http://technet.microsoft.com/en-us/library/bb123756(v=exchg.150).aspx