This means IT will only find out when the guest access pool is exhausted when it is too late, and costs start to rise.

However, there is no limitation or control on how many guest account invites any given users can send out as long as your company stays within its overall limit of the pool.

Cost and Control: Microsoft Teams only allows five (5) free guess access per end-user license.

As a result, guest access could be risky for a company’s infrastructure.

Security: After enabling guest access to external users, IT cannot control or dictate what security measures (such as password complexity, expiration, multi-factor authentication, etc.) external users will use to access their infrastructure.

However, this approach overlooks the following limitations of using MS Teams Guest Access. To get around the problem of interoperability between MS Teams and S4B Servers, Microsoft is recommending MS Teams customers to use the Guest Access to communicate with their external partners. This is going to be a problem as Microsoft plans to support customers on Skype for Business Server (S4B) 2015 or 2019 until 2025.įigure 2 – Skype For Business Server lifecycle As of February 25, 2019, Teams doesn’t support native federation without the user of the SIP profile being homed in Skype for Business Online.” “Currently, to federate within the Microsoft Teams app to an external user outside of your organization who’s not currently a guest of your Azure Active Directory (Azure AD) or tenant, you must be correctly set up for hybrid and moved to Skype for Business Online.

Even today, this kind of federation is not available already for some customers as it requires a Hybrid Skype setup: Since Microsoft is also retiring the SIP interoperability gateway of Skype for Business Online, customers on Microsoft Teams can not communicate with their external partners on S4B Server. Figure 1 – Microsoft Teams to Skype Onprem federation over the interoperability gateway

When is skype for business going away