Phoenix Network Forums

Please bear with my question. I have signed up also for a free shell account in order to try it and have more understanding about it.

For MS Windows users, I understand that one needs to have a shell account in order for some applications to run. But my question is, shell accounts are usually run on *nix servers. Why can't any linux user set up his own shell account? I use FC3 and I definitely see a bash shell.

Is it because a shell account needs to be run 24/7? And a personal linux desktop does not run 24/7? I was able to successfully setup an ftp server on my linux deskop. And I also see some other servers (web, email, etc.) that I can potentially setup using my desktop. Why is shell account different?

Again, I am basically a medical doctor who happens to tinker the computer as a hobby. So there are many things that I also don't understand. My use and understanding of linux is based on my trial and error experiences.

Thanks.

I think thats the general feeling, it's a 24 hour access issuse as well as the fact that it adds another layer between you and the destination.

You're connecting to the shell and connecting to the other area from there, As well as the use of webhosting etc.

actualy you need a SSH 'server'.
SSH is the only secure protocol to have shell access to a server without having great risk of password intercepting.

The point is that many users have leased lines, so they get disconnected periodically. For instance, my ISP drops my connection every 24 hours and then I automatically get a new IP address, which is bad. I'm already using DynDNS, but that's no solution. When my connection drops and I get a new address assigned, then most DNS caches still assume the old IP address and don't even bother looking the new address up again.

bart416 wrote:actualy you need a SSH 'server'.
SSH is the only secure protocol to have shell access to a server without having great risk of password intercepting.

That's true, but only if you use it wisely. If you do password authentication only, then the protocol as almost as secure as Telnet. You need to do some sort of cryptographic authentication rather than passwords. I like public key authentication, because I can use the same single key for as many servers as I want, without security problems. Also I can give and take access to/from other users without the need to change my key. In password authentication I'd need to change the passwort to keep him out.

Edit: By the way - as soon as we get quantum computers, there will be no secure protocols anymore, because those computers destroy the security of asymmetric cryptography. =)

mm_freak wrote:The point is that many users have leased lines, so they get disconnected periodically. For instance, my ISP drops my connection every 24 hours and then I automatically get a new IP address, which is bad. I'm already using DynDNS, but that's no solution. When my connection drops and I get a new address assigned, then most DNS caches still assume the old IP address and don't even bother looking the new address up again.

bart416 wrote:actualy you need a SSH 'server'.
SSH is the only secure protocol to have shell access to a server without having great risk of password intercepting.

That's true, but only if you use it wisely. If you do password authentication only, then the protocol as almost as secure as Telnet. You need to do some sort of cryptographic authentication rather than passwords. I like public key authentication, because I can use the same single key for as many servers as I want, without security problems. Also I can give and take access to/from other users without the need to change my key. In password authentication I'd need to change the passwort to keep him out.

Edit: By the way - as soon as we get quantum computers, there will be no secure protocols anymore, because those computers destroy the security of asymmetric cryptography. =)

We can pull up encryption to unbelieveable levels then
So it wouldn't realy make a diffrence at all.
New technolegy = new encryption to secure it.

bart416 wrote:We can pull up encryption to unbelieveable levels then ;)
So it wouldn't realy make a diffrence at all.
New technolegy = new encryption to secure it.

The first quantum computer will work before there is a way to use quantum cryptography. Also you had to spread quantum computers to everyone over the whole internet and create some kind of second channel between them. That means that effectively internet security will be broken for a few years. No secure authentication anymore, but yet still secure normal symmetric cryptography.

Also you need quantum computers with enough Qubits to break, say, an RSA key. For a specific key size, someone needs to build a quantum computer for breaking that key. And building a stable QC becomes exponentially more difficult with the number of Qubits.

Quantom Computing Just so lay people dont have read $150 text books on quantum computers and theory.. This is a normal book that floats around Border, BN, and Amazon..

i think with shell account, you can even do more sophisticate thing, like bypassing draconian firewall by using tunnel over ssh

Yeah, 24/7 is a definite factor, plus having a shell account usually means you have someone [ie the admin for the shell server] to talk to if you need help with anything. Although you have help forums if you try to run one yourself, it is just always nice when you can go straight to someone you know should be knowledgeable.

Also, it means that you don't have to deal with the administrative hassle of troubleshooting things when your box dies, or about security issues.

And then, also for me, my IP changes almost every three hours. I still don't know why, lol. *boggles* Stupid Verizon

goose wrote:Quantom Computing Just so lay people dont have read $150 text books on quantum computers and theory.. This is a normal book that floats around Border, BN, and Amazon..

Quantum computers are a purely theoretical construct. They're not proven to be possible. Some quantum mechanics interpretations even state that there is no quantum world. However, an experiment with quantum computing has factored the number 15 using Shor's algorithm.

Another thing about shells is the bandwidth.. You see, I can set up a shell from my home pc, but that has a terrible low bandwidth.. And even if it runs 24/7 you need to buy a UPS for eventual powerdowns and basically *nix systems are very internet oriented, so if you don't have a proper bandwidth they can be quite boaring.. - that's where shells come in!

zenx wrote:... and basically *nix systems are very internet oriented, so if you don't have a proper bandwidth they can be quite boaring.. - that's where shells come in!

Really? I've never noticed that. I do all the stuff with my Linux box, which other people do with a Windows box. This includes playing games, office work and other stuff.

mm_freak wrote:
Really? I've never noticed that. I do all the stuff with my Linux box, which other people do with a Windows box. This includes playing games, office work and other stuff.

(Yeah, you're probably right.. ;o)) cuz you can afford a proper computer ;o))
If I had one I wouldn't need a shell. cuz that would be the shell and I would be the admin ;o)) )
But anyway bandwidth is essential too ;o)

zenx wrote:(Yeah, you're probably right.. ;o)) cuz you can afford a proper computer ;o))
If I had one I wouldn't need a shell. cuz that would be the shell and I would be the admin ;o)) )

My current system has been installed on a Pentium 1 with 233 MHz and 64 MB of RAM (later upgraded to 128 MB). Now I have a newer computer, a Duron 1.6 GHz with 256 MB RAM. Just put the old hard-disk into the new computer and it works fine. =)

zenx wrote:But anyway bandwidth is essential too ;o)

Not if you have installation CDs. For upgrading you still need an internet connection (56K is enough, if you have a flatrate), but that applies to all other operating systems, too. =)

Downloading ISOs on dialup = hell...

You really do need bandwidth. But windows and OS X updates are big too. Everyone should really have broadband now...