If your organization deployed Microsoft Exchange Server 2007 in a cross-forest topology, you must implement synchronization of the following attributes for Lync Server 2010 when deployed in a central forest.

If Lync Server 2010 is deployed in a central forest, the same attributes need to be synchronized for the contact object in the central forest.

You must also synchronize the mailbox in the Microsoft Exchange Server forest.

The following attributes must be synchronized from the user object to the contact object.

• ObjectSid
  
  
• telephoneNumber
  
  
• displayName
  
  
• givenName
  
  
• sn (surname)
  
  
• physicalDeliveryOfficeName
  
  
• l (city)
  
  
• st (state)
  
  
• Country
  
  
• Title
  
  
• Mail
  
  
• Company
  
  
• Cn
  
  
• thumbnailphoto
  
  
• manager
  
  
• Department
  
  

The following table shows how attributes are mapped from a user object to a contact object using the example user, User A.

Attributes on User and Contact Objects

Attribute	User A	Contact for User A
Cn	UserA	UserA
ObjectSID	sidA
MsRTCSIP-OriginatorSID		sidA
telephoneNumber	555-1234	555-1234
displayName	User A	User A
givenName	Dylan	Dylan
surname	Miller	Miller
physicalDeliveryOfficeName	4500	4500
l (city)	Redmond	Redmond
st (state)	WA	WA
Country	U.S.A	U.S.A
Title	Director	Director
Mail	userA@contoso.com	userA@contoso.com
Company	Contoso	Contoso
ProxyAddresses	sip:userA@contoso.com	sip:userA@contoso.com
thumbnailphoto
manager	User A	User A
Department	Department	Department

The following attributes must be synchronized across forests for distribution group expansion to work in a cross-forest scenario.

• ObjectSid
  
  
• Mail
  
  
• displayName
  
  
• groupType
  
  
• Manager
  
  
• Distinguished Name (DN)
  
  

The following table shows how attributes are mapped from a user object to a contact object using the example group, Group A.

Attributes on Group and Contact Objects

Attribute	Group A	Contact for Group A
Cn	GroupA	GroupA
displayName	GroupA	GroupA
groupType	Distribution Group - Universal
msRTCSIP-SourceObjectType		Distribution Group - Universal
Mail	GroupA@contoso.com	GroupA@contoso.com
Distinguished name (DN)	<distinguished name of group A>
msDS-SourceObjectDN		<Distinguished name of group A>
Manager		Manager

For group–to-contact synchronization, the attribute msDS-SourceObjectDN on the contact should be populated with the DN of the group that is used in the forest where the group is managed.