Joining end-to-end encrypted online conferences using cached user credentials

1 . A method comprising:

storing, by a conference client of a first user, one or more user credentials in a cached list of user credentials, wherein one or more user credential included in the cached list of user credentials corresponds to one or more other user for each of one or more previous online conferences in which the first user has participated;

for a particular online conference to which the first user seeks to join, determining whether one or more particular user credentials for particular users participating in the particular online conference are not included in the cached list of user credentials;

based on determining that at least one particular user credential for the particular online conference is not identified in the cached list of user credentials, obtaining, by the conference client of the first user, the at least one particular user credential; and

enabling the first user, via the conference client, to join the particular online conference using one or more of the at least one particular user credential or one or more other user credentials included in the cached list for the particular users participating in the particular online conference.

2 . The method of claim 1 , wherein the particular online conference is a Messaging Layer Security (MLS) protocol end-to-end encrypted online conference.

3 . The method of claim 1 , further comprising:

for the particular online conference to which the first user seeks to join, obtaining, by the conference client from a conference server for the particular online conference, each of a corresponding hash for each of a user credential for each of the particular users participating in the particular online conference.

4 . The method of claim 3 , further comprising:

comparing, by the conference client of the first user, each corresponding hash for each of the user credential for each of the particular users participating in the particular online conference to each of a corresponding hash of each corresponding user credential included in the cached list of user credentials to determine whether one or more particular user credentials for the particular users participating in the particular online conference are not included in the cached list of user credentials.

5 . The method of claim 4 , wherein based on determining that at least one particular user credential for the particular online conference is not identified in the cached list of user credentials, the obtaining includes requesting, by the conference client of the first user, the at least one particular user credential.

6 . The method of claim 5 , wherein the conference client of the first user requests the at least one particular user credential from the conference server or from another server.

7 . The method of claim 1 , further comprising:

for the particular online conference to which the first user seeks to join, sending, by the conference client of the first user, a corresponding hash of each corresponding user credential included the cached list of user credentials to a conference server for the particular online conference.

8 . The method of claim 7 , further comprising:

comparing, by the conference server, each corresponding hash of each corresponding user credential obtained from the conference client of the first user to each of a corresponding hash of each corresponding user credential for the particular users participating in the particular online conference to determine whether one or more particular user credentials for the particular users participating in the particular online conference are not included in the cached list of user credentials.

9 . The method of claim 8 , wherein based on determining, by the conference server, that at least one particular user credential for the particular online conference is not identified in the cached list of user credentials, the obtaining includes obtaining the at least one particular user credential sent by the conference server to the conference client of the first user.

10 . The method of claim 9 , further comprising:

obtaining, from the conference server, one or more index values in which each index value identifies each of a corresponding user credential for the particular users participating in the particular online conference that are included in the cached list of user credentials.

11 . The method of claim 1 , wherein at least one user credential is stored in the cached list of user credentials based on an external process.

12 . The method of claim 11 , wherein the external process includes at least one of:

storing in the cached list of user credentials the at least one user credential based on a contact list of other users associated with the first user; or

selecting the at least one user credential to add to the cached list of user credentials based on at least one other user being identified as a member of an organization of interest.

13 . One or more non-transitory computer readable storage media encoded with instructions that, when executed by a processor, cause the processor to perform operations, comprising:

storing, by a conference client of a first user, one or more user credentials in a cached list of user credentials, wherein one or more user credential included in the cached list of user credentials corresponds to one or more other user for each of one or more previous online conferences in which the first user has participated;

for a particular online conference to which the first user seeks to join, determining whether one or more particular user credentials for particular users participating in the particular online conference are not included in the cached list of user credentials;

based on determining that at least one particular user credential for the particular online conference is not identified in the cached list of user credentials, obtaining, by the conference client of the first user, the at least one particular user credential; and

enabling the first user, via the conference client, to join the particular online conference using one or more of the at least one particular user credential or one or more other user credentials included in the cached list for the particular users participating in the particular online conference.

14 . The media of claim 13 , wherein the particular online conference is a Messaging Layer Security (MLS) protocol end-to-end encrypted online conference.

15 . The media of claim 13 , wherein the instructions, when executed by the processor, cause the processor to perform further operations, comprising:

for the particular online conference to which the first user seeks to join, obtaining, by the conference client from a conference server for the particular online conference, each of a corresponding hash for each of a user credential for each of the particular users participating in the particular online conference.

16 . The media of claim 13 , wherein the instructions, when executed by the processor, cause the processor to perform further operations, comprising:

for the particular online conference to which the first user seeks to join, sending, by the conference client of the first user, a corresponding hash of each corresponding user credential included the cached list of user credentials to a conference server for the particular online conference.

17 . A system comprising:

at least one memory element for storing data; and

at least one processor for executing instructions associated with the data, wherein executing the instructions causes the system to perform operations, comprising:

storing, by a conference client of a first user, one or more user credentials in a cached list of user credentials, wherein one or more user credential included in the cached list of user credentials corresponds to one or more other user for each of one or more previous online conferences in which the first user has participated;

for a particular online conference to which the first user seeks to join, determining whether one or more particular user credentials for particular users participating in the particular online conference are not included in the cached list of user credentials;

based on determining that at least one particular user credential for the particular online conference is not identified in the cached list of user credentials, obtaining, by the conference client of the first user, the at least one particular user credential; and

enabling the first user, via the conference client, to join the particular online conference using one or more of the at least one particular user credential or one or more other user credentials included in the cached list for the particular users participating in the particular online conference.

18 . The system of claim 17 , wherein the particular online conference is a Messaging Layer Security (MLS) protocol end-to-end encrypted online conference.

19 . The system of claim 17 , wherein executing the causes the system to perform further operations, comprising:

for the particular online conference to which the first user seeks to join, obtaining, by the conference client from a conference server for the particular online conference, each of a corresponding hash for each of a user credential for each of the particular users participating in the particular online conference.

20 . The system of claim 17 , wherein executing the causes the system to perform further operations, comprising:

for the particular online conference to which the first user seeks to join, sending, by the conference client of the first user, a corresponding hash of each corresponding user credential included the cached list of user credentials to a conference server for the particular online conference.