configuring access for internal interface only in cisco

I currently have tested a new router which is to be used for IPSec and consequently has a real world adddress on one side of the router - i want to be able to login via telnet from internal IP's but i can also log in via the real world address - what is the easiest way to restrict this access and olny allow internal networks to go via the LAN address?
redmayneAsked:
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

x
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

lrmooreCommented:
access-list applied to the vty lines
Assume: internal LAN = 192.168.200.0
Assume: real world IP = 23.45.67.8

access-list 6 permit 192.168.200.0 0.0.0.255
access-list 6 permit 23.45.67.8
line vty 0 4
 access-class 6 in

! Done

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Networking

From novice to tech pro — start learning today.