Hi, It's bit silly question but I have to ask. I am using cisco-access server to connect various network equipments. So I need to know while using ssh client how I can open separate window for my each device-session connected to access server?
The details of how to do this will depend somewhat on how your access server is configured and somewhat on what capabilities your ssh client offers. Essentially what you want to do is to open multiple windows in your ssh client (or multiple instances of the ssh client if the client does not support multiple windows). For example I typically use SecureCRT as my ssh client and it happily allows me to open as many windows as I want.
Each time you open a new window in the ssh client you want to connect to the access server and open a connection to another network device. One limitation here may be how many sessions the access server allows you to establish. If your access server is a Cisco IOS router then the limitation is probably how many vty ports are configured. By default Cisco IOS routers support at least 5 vty ports and most can be configured for more. There may also be a limitation on how many sessions depending on how you authenticate your login. If you are using an authentication server (such as ACS) then there may be a limitation on how many simultaneous sessions it will allow.