What are directory services? Directory services are some sort of database where you can store data of customers, partners, employees, and these days as well, things. So they're growing beyond what they have traditionally. There is that concept of there has been a concept of X 500 ahead. And the directory is the data store with directory service, which provides the access for delivering data into the directory and getting data out of the directory. So it is them where applications that need information about customers, partners, et cetera, and this information where they also can authentic indicate. And so for most director can authenticate against.
So what are key capabilities of such a directory service? It starts is storing identities and related attributes in a central place. So the directory is this place where you have a lot of this information. You might have multiple directories, but usually directories cover a range of applications in a range of use cases. And you should always try to restrict the number of the directories. It is very important to provide efficient read access to the directory data, because this is the sort of highest capability, high performance use case you need to support. For instance, around authentication around reading additional attributes from the directory, that's already said, it is very common that directories provide authentication services such as an LTA authentication. They also frequently support some replication. So most of the directory services are able to have multiple instances of the directory and to synchronize data either in a, what is commonly called master slave replication.
So one master where you change and a couple of places where this data can be stored them or in the master master or multi-master way where you have multiple places where you can make the changes, then further, they have a schema. So the data structure that can be somewhat more Richard like this buildup directories, it can be also more flexible, which is potentially the case in new types directors, which build on draft databases. And this is what allows you to add data if required, depending on the type of directory that might be more broad or more restricted access. So traditional protocol, so called light weighted directory access protocol, but we also see more and more so called rest APIs specific type of APIs, which allow access to that information.
