You need to install rdesktop package for this purpose. For RHEL machine you can use the below command
To check for existing package
# rpm -qa | grep rdesktop
To install a new package
# yum -y install rdesktop
Once the package is installed run the below command from the GUI console of your Linux box
NOTE: rdesktop will only work from GUI console and not from CLI or putty
# rdesktop (machine_name_to_connect)
# rdesktop 192.168.1.7
And this should do the magic.
In case you get any graphical console related error follow the below link
Xlib: No protocol specified
Iptables rules for rdesktop
To allow a particular subnet to which your machine can connect
# iptables -I OUTPUT -d 192.168.1.0/24 -p tcp --dport 3289 -j ACCEPT
To block a subnet to which your machine can connect
# iptables -I OUTPUT -d 192.168.1.0/24 -p tcp --dport 3289 -j REJECT
Follow the below links for more tutorials
What is the difference/comparison between Unix and Linux ?
What are the maximum and minimum limits for RHEL 4 vs 5 vs 6 ?
Step by Step Linux Boot Process Explained In Detail
What is the difference between ext3 and ext4 filesystem in Linux ?
How to configure Private Network in VMware Workstation
10 examples to help you understand top command usage in Unix/Linux
Configure Red Hat Cluster using VMware, Quorum Disk, GFS2, Openfiler
Tutorial for Monitoring Tools SAR and KSAR with examples in Linux
15 tips to enhance security of your Linux machine
Why is Linux more secure than windows and any other OS
Understanding Load Average in Linux and when to be worried about it?
Disk Attachment Technology FC vs SAS vs iSCSI
Understanding UMASK value in Linux
How to keep a track of all the commands run by any user in Linux
How do you check Linux machine is Physical or Virtual remotely?
RAID levels 0, 1, 2, 3, 4, 5, 6, 0+1, 1+0 features explained in detail