5
Terminal reset
When a terminal fails to communicate with the receiver, you can re-establish communication by
pressing the terminal reset hotkey on the terminal. The initiator will disconnect and then re-establish
the TCP connection with the receiver.
TCP parameter configuration
TCP buffers store the data exchanged between the initiator and receiver. You can set the following
TCP connection parameters:
•
Receive buffer size.
•
Send buffer size.
•
Non-delay attribute.
•
Keepalive interval and number.
Terminal buffer parameter configuration
The router uses terminal buffers to store the data exchanged with terminals. You can set the
following terminal buffer parameters:
•
Whether to clear the receive buffer before receiving data.
•
Receive buffer size.
•
Send buffer threshold.
•
Maximum size of data to be sent to the terminal at one time.
RTC terminal authentication
To enhance security, the RTC server can perform password authentication on RTC clients.
Authentication succeeds only when the RTC server and the RTC client are configured with the same
password.
Terminal access VPN instances
RTC terminal access supports VPN instances. Terminals connected to an RTC client can be
grouped into different VPN instances. This allows a terminal in a VPN instance to access a remote
terminal that is in the same VPN instances.
TCP NODELAY
In TCP many-to-one or TCP one-to-one transparent transmission mode, the RTC client and the RTC
server use the Nagle algorithm to prevent network congestion caused by a large number of TCP
packets. For more information, see RFC 896.
The Nagle algorithm also causes time delay during TCP packet transmission, especially for
interactive applications. The RTC client and the RTC server allow you to disable the Nagle algorithm
by setting the TCP_NODELAY option.
Link backup
One terminal or two terminals can connect to two synchronous serial interfaces of a router through
two links. To configure backup between the two links, you can configure the two synchronous serial
interfaces as primary and backup interfaces for the terminal access. When the primary interface is
operating correctly, the router and the terminal communicate through the primary interface. When
the primary interface fails or when the number of cyclic redundancy check errors on the primary
interface reaches the upper threshold, the backup interface takes over. The primary interface takes
over again when it recovers from a failure condition.
Compatibility mode support
RTC terminal access supports the following data transmission mode: characteristic mode and
compatibility mode. The RTC server and the RTC client must operate in the same data transmission
mode.
