Connection via telephone line (56k modem - LAN)

I'm not exactly sure I understand what you want:

1) If your desktop PC has a public IP address (visible on the internet), you can generally connect it (unless blocked by a firewall, etc.) by putting the other one with the 56K modem on the internet with any ISP and doing "ssh <number_ip_desktop_pc>", provided that the desktop PC is running Linux with an SSH server; I don’t know if it's easy on Windows, even advisable. So that's the obvious method.
However, if your desktop PC does not have a public IP but only a private IP like 192.168.blabla because your office is using a NAT router to share the connection, then SSH access to your desktop PC is not easily possible (it would be hidden behind the router). Technically, you would need to forward port 22 (for SSH) to your desktop PC, but I doubt that this is something feasible in your situation (it would require actions on the router by the office administrator, and they probably don’t want to hear about it, understandably). Even with a public IP, it is possible that the office administrator has set up a firewall that blocks SSH (and all other ports) to your desktop PC. In such a situation, you would need to SSH to another gateway machine (at the office) and then SSH to your desktop PC, but this would need to be set up at your office (probably not?).

2) So technically, you could also establish an SSH connection from the desktop PC to your PC with the 56K modem; that is always possible but not very practical, especially since the 56K connection must be established permanently, and I'm not sure you want to connect from the desktop PC to the 56K PC?? I have the impression it's rather the other way around?? If we do this, you also need to put a good firewall on the 56K PC (allowing SSH only from the IP of the desktop PC and nothing else).

3) Another possibility would be to set up a 56K modem in the office, connect it to a phone nearby, and make a direct PPP connection between the desktop PC and the other PC. This way, you wouldn’t go through the internet. In this case, you would need to configure a PC as a PPP server. It's possible but not easy, let's say not very obvious. You could use IP numbers like 192.168.0.x with x=1 and 2 (something very different from the office IPs to avoid conflicts). In terms of costs, you would just have to pay for the phone communication.
For details on how to do this (in Linux), you can look at different HOWTOs:
http://www.tldp.org/HOWTO/HOWTO-INDEX/networking.html#NETDIALUP
especially the sections: "call-back" and "ppp-HOWTO".
If you are looking for French translations of the HOWTOs, you can check here:
http://www.ibiblio.org/pub/Linux/docs/HOWTO/translations/fr/
(there are ps, pdf, html formats as you want, but you need to download, unpack and read at home).
But if you don't have experience with networking and/or Linux, it's not obvious.</number_ip_desktop_pc>

Hi,
I believe the request is rather what you (kmf31) indicate in point 3, the rest does not correspond.
Indeed, this is called remote access via PSTN modem.
On Windows, it's quite easy to do once the modem is installed.
Access can be done either in PPP or SLIP ;-) Serial IP.
Under Linux, there's probably a module for incoming connections pppd or slip on a ttysx.
Also, it's important to know that a V90 or V92 modem (56K) will only connect at 33.6 at best directly with another modem (V34bis).
--
And ... There you go!

Thank you for this information.
Indeed, the solution of remote access via RTC modem suits me best.
However, I still have a small question.
Can I have an RTC modem on one side and an ADSL router modem on the other (the one that is installed at the office)? The admin can make changes if necessary, but before making a request, I want to be sure of the possibilities.
Thank you,
Stef.

If you talk about a direct connection without going through the internet there is only RTC-RTC through the telephone line with the PPP protocol.
If you want to do it with an ADSL modem, it is technically impossible. You would need to have a DSLAM (the big cabinets of ISPs that are found in your NRA, the connection node) on the other side. Moreover, the ADSL signal with high frequencies only works for the first link: home-NRA but not further (and then in the NRA there are DSLAMs that transform ADSL into network stuff to put it on the internet).

On the other hand, with internet you can very well do:
PC1 internet with RTC
PC2 internet with ADSL

of course with ISPs for both connections. It also works like that with ADSL for both PCs.

Later, we can connect via SSH etc. as described in possibilities 1 and 2 of my first post. Here, you need to remember the IP numbers for both connections and also properly configure the firewalls. Apart from that and the fact that you need to be careful about security, it works very well and is relatively easy.

Hello,
thank you

Well, rest assured that both machines have a dial-up modem; then find remote access software to control your remote workstation. Then install the client and server application of the software.
In principle, if your firewalls are disabled on both machines, then you will be able to connect them.

Hello,
I would like to share the internet between my Windows Vista computer which has a 56k modem and my little brother's computer which has a Windows 2000 that does not have a 56k modem. -_-

Thank you in advance for your response!!!

Désolé, je ne peux pas vous aider avec ça.

Thank you so much!!!
Guys, I don't know what I would have done without you!!!

Il faut maîtriser correctement les commandes du système LINUX
et puis installer les packages nécessaires
mrsiiiiiiii.