Microsoft Teams allows you to communicate and collaborate with people outside your organisation. There are two different ways that this can happen. External access (what was federation), allows you to find, call and chat with users in other domains. Guest access lets you add individuals to your teams as guests using their email address.
External access (federation) is used when you need to let external users in other organisations find, call, chat and setup meetings with your organisation. External users have no access to your organisation’s teams or team resources. External access is required to communicate with external organisations who are on Skype for Business (Online or On-Premise).
A guest is someone who isn’t a member of your organisation. They don’t have a work account with your organisation. For example, guests may include clients, partners, vendors or suppliers. Anyone who is not part of your organisation can be added as guest in Teams.
This means that anyone with a business account (that is, an Azure Active Directory account) or consumer email account (with Outlook.com, Gmail.com or others) can participate as a guest in Teams, with access to teams and channel experiences.
Guest access is used to add an individual to a team where they can do all the same as an external access user as well as collaborate on files hosted in the team using office 365 apps, such as World, Excel or PowerPoint.
Compare External and Guest Access
The below table from Microsoft explains what feature is available to the different users personas.
|Feature||External Access Users||Guest Access Users|
|User can chat with someone in another company||Yes||Yes|
|User can call someone in another company||Yes||Yes|
|User can see if someone from another company is available for call or chat||Yes||Yes*|
|User can search for users across External tenants||Yes**||No|
|User can share files||No||Yes|
|User can access Teams resources||No||Yes|
|User can be invited to a meeting||Yes||Yes|
|Additional users can be added to a chat with an external user||No***||N/A|
|User is identified as an external party||Yes||Yes|
|Presence is displayed||Yes||Yes|
|Out of office message is show||No||Yes|
|@Mentions are supported||Yes****||Yes|
|Make private calls||Yes||Yes|
|Allow IP Video||Yes||Yes|
|Screen Sharing Mode||Yes****||Yes|
|Allow meet now||No||Yes|
|Edit Sent messages||Yes****||Yes|
|Can Delete sent messages||Yes****||Yes|
|Use Giphy in conversation||Yes****||Yes|
|Use memes in conversation||Yes****||Yes|
|Use stickers in conversation||Yes****||Yes|
*Provided that the user has been added as a guest and is signed in a guest to the guest tenant.
**Only by email or Session Initiation Protocol (SIP) address.
*** External (federated) chat is 1:1 only.
****Supported for 1:1 chat for Teams Only to Teams Only users from two different Organisations. (In Preview)
Guest access is an Organisation-Wide Teams setting, by default Guest access is disabled. External access is enabled for all external domains by default. If you add a blocked domain all other domains are allowed, however if you add an allowed domain, other domains will be blocked unless they are also in the allowed domains list.
Watch out for the next post about managing Guest and External Access.