rsh runs perfectly in normal user but not in root, very strange, why?

When I run command, rsh localhost pwd as a root It shows below output. connect to address 127.0.0.1 port 544: Connection refused Trying krb4 rsh... connect to address 127.0.0.1 port 544: Connection refused trying normal rsh (/usr/bin/rsh) rcmd: socket: Permission denied When I run the same command from normal user named service. Then it shows below output. connect to address 127.0.0.1 port 544: Connection refused Trying krb4 rsh... connect to address 127.0.0.1 port 544: Connection refused trying normal rsh (/usr/bin/rsh) /home/service Why this behavior happening?