R2511-HP MSR Router Series Terminal Access Configuration Guide(V5)

As shown in Figure 3, data is transmitted in ciphertext between Router A and the FEP. Router A and the

FEP that runs the program ttyd/ccbtelnetd/sshd are responsible for data encryption and decryption. At

present, the supported encryption algorithms are as follows:

• Advanced encryption standard (AES) encryption is supported by TTY terminal access.

• AES and RC4 encryption are supported by ETelnet terminal access.

• RSA and DSA encryption are supported by SSH terminal access.

Figure 3 Data encryption procedure between router and FEP

Automatic link establishment

You can enable this function and configure the automatic link establishment time in terminal template

view. When the terminal is in the "OK" state (meaning the physical connection is normal), the initiator

automatically establishes a TCP connection to the receiver after the specified period. If the automatic link

establishment function is disabled on the terminal, you must manually establish a link. In this mode, the

initiator establishes a TCP connection to the receiver only when the operator enters a character on the

terminal.

Automatic link teardown

You can enable the function and configure the automatic teardown time for the terminal in terminal

template view. When the terminal device and the initiator are disconnected from each other, the terminal

enters the "down" state. After a specified period of time, the initiator automatically tears down the TCP

connection to the receiver. The TCP connection always remains active if the automatic link teardown

function is disabled.

TTY one-to-one access

In TTY one-to-one access, each terminal communicates with the FEP (TTY) through a TCP connection to

achieve optimum communication quality and highest communication speed under various link states.

You can use this mode to achieve high communication speed on low-speed links by adjusting parameters.

This mode can also meet the need for frequent and massive printing.

Terminal display language configuration

The initiator generally sends some unsolicited information, such as menus and link establishment

information, to the terminal. To meet different language needs, the prompt information can be displayed

in either English or Chinese (the default).

Screen saving

Screen saving is implemented in the following ways:

• A terminal can display the saved screen contents after receiving specific control characters from a

router.