OSF DCE Administration Guide--Core Components

OSF DCE Administration Guide—Core Components

33.1.4 Constraints on Transitive Trust Relationships

To prevent the widespread proliferation of trust relationships that could result in

unwieldy administrative burdens and weakened security, the DCE Security Service

imposes the following three rules on transitive trust relationships:

1. Any number of descendent cells can be traversed by a transitive trust relationship,

and any number of ancestor cells can be traversed by a transitive trust relationship.

2. No more than one direct trust peer relationship can be traversed by a transitive

trust relationship. (A direct trust peer relationship is a direct trust relationship

between cells that are neither ancestors nor descendants of each other in the

naming hierarchy.)

3. Once a hierarchical trust relationship traverses a direct trust ancestor and an

optional direct trust peer, it cannot traverse to an ancestor of the peer cell. In other

words, once a transitive trust path goes up and across, it can’t go up.

The ramiﬁcations of these rules are explained in the following paragraphs.

Rule 1:

Any number of descendent cells can be traversed in a hierarchical trust

relationship, and any number of ancestor cells can be traversed by a transitive trust

relationship.

For example, in Figure 33-2, peer Cells A and B have a direct trust relationship. Cell A

has a transitive trust relationship with cells B/C and B/C/D.

Figure 33-2. Direct and Transitive Trust Relationships

Transitive trust relationshps between

cell A and cells B/C and B/C/D

direct trust

The previous conﬁguration also makes possible the transitive trust relationship between

B and cell B/C/D shown in Figure 33-3.

Figure 33-3. Cell Traversal in Transitive Trust Relationships

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