[NTLUG:Discuss] identd? What's it for?

[Richard Cobbe]

General TCP/IP networking question for y'all:

Since I've got a DSL link and a static IP, I'm using ipchains to block
unwanted access to my PC.  According to my logs, a largish number of the
blocked connections are headed towards TCP port 113, the auth daemon,
identd.

Now, I've read the man page for identd, and I understand more or less what
it does.  So what's it for?  Why would someone want to connect to an identd
server?  Am I actually breaking anything by disabling access to that port?

Richard