SP related to ANYTHING refers to Service Pack. Service Packs are addon programs that need to be applied to base softwares or apps to cover certain vulnerabilities or add extra features. For Tomcat, installing its SP would be very necessary as it is a web server and any loophole therein should be immediately fixed so that it is not exploited. Hence the Tomcat SP.
With the little information that you have provided , i assume you mean to look for Web Host providers who offer to host JSP websites. Tomcat converts JSP into servlets and acts as a web server and is required to host java powered sites. An example of Tomcat Sevice provider is http://www.oxxus.net/hosting_java.htm .
thx for the reply,
I think it would be Service Pack only, because this question was asked in the interview, like he asked which SP do you use for your Tomcat but when I asked what is SP he din't told it clearly like he said Service and I could not catch the word he pronouced with P.