Server Fault is a question and answer site for system and network administrators. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I am considering establishing a one-way trust relationship between a local Active Directory domain and a remote (across a WAN VPN) Active Directory domain. Since the bandwidth between sites is limited, I need to estimate how much additional network traffic will be generated by the trust relationship in idle (i.e. how much bandwidth to keep them "In Synch" if necessary), and how much additional traffic between sites per session (if any). I'm not expecting any additional usage to occur, but am trying to simplify user administration.

share|improve this question
up vote 5 down vote accepted

There is nothing to keep in "sync." After the trust is created, there's no idle traffic. The only time traffic is generated is when cross-forest references need to be made for things like group membership, resource access, LDAP queries, etc and this is generally minimal.

There's really no way for anyone to say how much bandwidth will be used between sites, but unless you have a crazy architecture, it shouldn't be a lot.

share|improve this answer

As MDMarra stated in his answer, there's no traffic between the two domains until and unless a user (or appliocation in one domain needs to authenticate to and access resources in the other domain. An AD Trust is a static entity in the sense that there's no syncing, no replication, etc.

What you should determine/measure is the volume of traffic when the Trust is being used for whatever you're creating it for, which is presumably to access resources of some type in one domain from the other domain.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.