With the -b option you can select one of the IP addresses of your machine.
One machine might have several NIC installed, i.e. 127.0.0.1(localhost) and the real ip by default. Server machines might have several i.e. 184.108.40.206 internal and a.b.c.d external.
So you are able to configure services to an internal or external IP address.
By default the JBoss configuration has to interfaces public and management for security they are bound to 127.0.0.1 by default.
You can change that in the standalone*.xml or use the -b -bmanagement option during runtime.
You can not use other IP addresses than the existing ones, the binding will fail.
If you use 0.0.0.0 as IP that means the services are bound against all existing NIC interfaces, but you might have issues in older versions as there was a bug.
Does that makes sense to you?