- Using RPC you can integrate directly with a part of the backend OTRS APIs which are relatively low level, using the Generic Interface you can use a bit higher level operations.
- While both interfaces are possible to use from different programming languages, especially .Net and Java coders will want to use the Generic Interface as it comes with WSDLs which much better match their tooling.
- For the rpc.pl there is just one username/password combination for all of OTRS, which gives full power (and possibilities) to the API using it. WIth Generic Interface you can authenticate with Agent or Customer logins and permissions will be respected.
So long story short, you would probably want to use the Generic Interface. But as you said not all operations are provided - currently just operations for tickets and for FAQ - so depending on what you want to achieve you might need to extend the interface a bit.
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