XAM, a SNIA defined interface standard supporting reference data archives, is starting to become real. EMC and other vendors are starting to supply XAM compliant interfaces. I could not locate (my Twitter survey for application vendors came back empty) any application vendors supporting XAM APIs but its only a matter of time . What does XAM mean for your data archive?
The problem
Most IT shops with data archives use special purpose applications that support a vendor defined proprietary interface to store and retrieve data out of a dedicated archive appliance. For example, many email archives support EMC Centerra which has defined a proprietary Centerra API to store and retrieve data from their appliance. Most other archive storage vendors have followed suit. Leading to a proprietary vendor lock-in which slows adoption.
However, some proprietary APIs have been front-ended with something like NFS. The problem with NFS and other standard file interfaces is that they were never meant for reference data (data that does not change). So when you try to update an archived file one often gets some sort of weird system error.
Enter XAM
It was designed from the start for reference data. Moreover, XAM supports concurrent access to multiple vendor archive storage systems from the same application. As such, an application supplier need only code to one standard API to gain access to multiple vendor archive systems.
SNIA released the V1.0 XAM interface specfication last July which defines XAM architecture, C- and JAVA-language API for both the application and the storage vendor. Although from the looks of it the C version of vendor API is more complete.
However, currently I can only locate two archive storage vendors having released support for the XAM interface (EMC Centerra and SAND/DNA?). A number of vendors have expressed interest in providing XAM interfaces (HP, HDS HCAP, Bycast StorageGrid and others). How soon their XAM API support will be provided is TBD.
I would guess what’s really needed is for more vendors to start supporting XAM interface which would get the application vendors more interested in supporting XAM. Its sort of a chicken and egg thing but I believe the storage vendors have the first move, the application vendors will take more time to see the need.
Does anyone know what other storage vendors support XAM today. Is there any single place where one could even find out? Ditto for applications supporting XAM today?
XAM is certainly attractive for us. We want to archive digital assets for posterity (ie forever) and we have to plan for technology obsolescence and regular migration to new platforms as part of the architecture. XAM promises vendor independence and an abstraction from the underlying storage format.
Mark Alexander
The Wellcome Trust
Mark, Yes XAM as it rolls out to other vendors has the promise to provide vendor independence. Tech obsolescence is an ongoing problem which is unlikely to go away anytime soon. Ray