Forefront Identity Manager (FIM) provides an out-of-the-box solution for GALSync which is commonly used by Exchange Server customers today.
Especially in current times when there is a lot of companies joining, organizing into groups or just cooperating on various integration levels. It is quite common in case of such organizations to have well connected companies (where you have so integrated IT organizations that you can connect directly to other organization Active Directory and read/write address book data) but as well some other satellite companies/sub organization connected in more loosely way.
In such case you can have additional contacts coming from these organizations which you may like to introduce into your GAL. These contacts can be delivered by using CSV files or other method.
You can provide as well some additional attributes like for example attributes related to organization (company, department, etc.).
Let's say you have your additional contacts prepared in CSV file including all necessary attributes. For example your file looks like:
CN, displayName, mail, mailNickname, givenName, sn, targetAddress
John Smith, John Smith (Partner Company), j.smith@partnercompany.com, j_smith_partnercompany_com, John, Smith, SMTP:j.smith@partnercompany.com
Richard Black, Richard Black (Partner Company), r.black@partnercompany.com, r_black_partnercompany_com, Richard, Black, SMTP:r.black@partnercompany.com
Add filters if required
You can extend GALSync by adding additional sources of addresses. Just need to remember what attributes you have to provide and what class to use to have it in easy way.
If your organization uses cloud based solutions and synchronizing with Azure AD using DIRSync you may be interested as well in following article by Paul Williams - GALSync and DirSync in harmony
Congratulations on the guru award.
Great article.