Kerberos - What is an SPN and why is it used

Question

I am trying to setup SPNEGO in Jetty using these instructions: https://wiki.eclipse.org/Jetty/Howto/Spnego.

What I would like to know is what is the SPN (from googling it looks like some sort of alias) and why is it actually used? (ie what does it add - extra security? if so - why?)

Thanks.

Answer 1

SPN is the Service Principal Name and is by no means a side characeter in Kerberos. Basically, it is the equivalent of the username, but for the server side. The Ticket-Granting Service knows about all Service Principals and their passwords, and encrypts the Service Ticket with that password. In order to acquire a Service Ticket for a certain service, obviously you must know its SPN.