The InCommon Federation Interoperability Working Group (FIWG) was chartered by the InCommon Technical Advisory Committee (TAC) in July, 2015 to help improve interoperability within InCommon and across scalable SAML federations more broadly. To quote the charter:
When InCommon was created 10+ years ago, it was an explicit goal to keep the bar for membership and operational participation as low as possible. This helped to grow the Federation to its current size. This has also hindered interoperation. Members cannot make any real assumptions about policy, practices, and the supported functionality at other member sites when attempting to interoperate. Both IdPs and SPs suffer from this problem. Areas that are affected include:
The work product of the working group is the SAML V2.0 Implementation Profile for Federation Interoperability . This is an implementation profile intended for use by SAML software engineers and architects as a normative guide for design of their software to meet the requirements of a scalable SAML trust model rooted in multiparty metadata exchange. It is a counterpart to the earlier saml2int  work on configuration of SAML software for a scalable deployment (more on that in the next section). Without the implementation requirements documented in this new work, it may be impossible for SAML implementations to meet the configuration requirements in saml2int.
Additionally, it is hoped that this work will be incorporated into federation software test suites such as fedlab . One of the core fedlab team members (also a Kantara WG-FI and eGov member/chair) was an active contributor to the document, and will help shepherd it into the test suite and through the Kantara process (more in “Recommendations” section). In turn, this should serve as a basis for InCommon and other operators to create test tool deployments on which to base other possible means of communicating compliance with this and other profiles, for example, entity category tagging for complying deployments.
Address deployment issues remaining on the Interop Issues List
or, charter a new working group to identify needed revisions to saml2int  and figure out a hand-off that factors in REFEDS and the Kantara WG-FI
Charter a new TAC working group to focus on InCommon deployment requirements (using the Interop Issues List as seed material)
Recommendations for Publication
The FIWG recommends that the TAC work with the Kantara WG-FI and eGov working groups to try and achieve consensus around a common profile for InCommon and the e-Government sector. This would increase interest in adoption and provide a long-lived home for the profile in a neutral body that already hosts the "saml2int" deployment profile that was produced by the R&E community. Multiple Kantara participants have expressed interest in this, and Rainer Hörbe has offered to help shepherd the draft through this process. In the event that consensus proves impossible, the draft could still emerge as a Kantara document, or alternatively the TAC may consider other options such as the REFEDS publication stream.
Note: Nick Roy and Ann West of InCommon have a meeting scheduled for Friday, March 4, 2016, to meet with Internet2 legal about the details of such a handoff of IP.
 SAML V2.0 Implementation Profile for Federation Interoperability
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 SAML 2.0 Interoperability Deployment Profile
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 Interop Issues List
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 InCommon Federation Interoperability Working Group Charter
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