c# - .Net Web App - How to make an LDAP connection using directory entry over UDP port 389

Question

I am attempting to make an LDAP connection to query active directory groups in my web application and by default it uses port 389 and connects via the TCP protocol. However due to security reasons i am only able to use port 389 via the UDP protocol but I am looking for help in how to code a way to connect to the active directory using the UDP protocol.

Currently I am using the DirectoryEntry class https://docs.microsoft.com/en-us/dotnet/api/system.directoryservices.directoryentry?view=dotnet-plat-ext-5.0 and running the web app in .net 4.8. I am looking to use to it to load all groups and members.

I have searched quite a bit and the only information i have found is that LDAP can be run over UDP and that particular method is referred to as cLDAP (connectionless LDAP) but cant find any information in how to code that.

Edit: After researching, i found this: https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-adts/3fad0ec9-414c-432a-ba0b-837c74091dd6 which states "Active Directory supports search over UDP only for searches against rootDSE". And specifically what I have found is that rootDSE gives information about the active directory itself but not the groups inside.

question from:https://stackoverflow.com/questions/65939564/net-web-app-how-to-make-an-ldap-connection-using-directory-entry-over-udp-por

Answer 1

After researching, i found this: https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-adts/3fad0ec9-414c-432a-ba0b-837c74091dd6 which states "Active Directory supports search over UDP only for searches against rootDSE". And specifically what I have found is that rootDSE gives information about the active directory itself but not the groups inside.