You bind Tomcat to a port as part of the setup anyway, otherwise you wouldn't be able to access it at all. By default sockets are accessible over the network from Linux, so provided you have an Internet connection from your server it should be fine (you may need to configure IPs/hostnames in Tomcat, so read the documentation). I don't really see that we can advise you how to get a connection from your server to the Internet in a Java forum (you need to make sure there is an Internet-accessible IP address assigned to your server first, and that the chosen port for Tomcat isn't firewalled off). You'd need to give the details to your network administrator.
Charles Lyons (SCJP 1.4, April 2003; SCJP 5, Dec 2006; SCWCD 1.4b, April 2004)
Author of OCEJWCD Study Companion for Oracle Exam 1Z0-899 (ISBN 0955160340 / AmazonAmazon UK )