I have been able to set up linux on my cable modem to connect to the internet with the static ip address assigned to me by cable operator, but I am unable to connect to my machine from the outside either by http(have apache running on port 80), ftp or telnet. Interesting enough, I can ping my machine from the outside. Could you tell me what files or what I am missing. I 'll appreciate any input.

Great article on cable modem setup.
My configuration is
Redhat 7.1 (2.4.2 smp)

thank

1. DON'T DOUBLE POST!!!!!

2. Please search this forum, this question get's asked so many times.

but anyway...
erm i'd guess that you've not enabled ftp or telnet. Look in /etc/xinetd.d/ftp and telnet and change

disabled = yes

to the obvious.
not sure about the httpd problem tho.

how do I enable httpd for incoming request.

Are u using NAT (Network Address Translation?
What are your local IP addresses?

If you are using NAT then you will probably have problem with incoming traffic.
When you recuest a public IP on the internet then the NAT server translates your private IP to your public IP and assigns a random port number to identify your host and the client program your are using.
This port number is only valid for the current session.
Your private IP addresses are hidden to the public internet and when the NAT server get a connection request it doesn't know what to do with it. To make your server on the private LAN you would have to assign static translation assignments for your private IP addresses. I don't know how to do this in linux , only know how to do this in Novell.