Digi 90000566_H manual Keepalive=onoff, Delayedack=0-1000

set service

keepalive={onoff}

Indicates whether or not TCP keepalives will be sent for specified range of network services. If set to on, keepalives will be sent, if it is off, keepalives will not be sent.

Configurable TCP keepalive parameters, for example, how many keepalives to send and when to send them are configured globally via the “set network” command (see "set network" on page 149).

nodelay={onoff}

Used to allow unacknowledged or smaller-than-maximum-segment- sized data to be sent for the specified range of network services.

The “nodelay” option disables Nagle’s algorithm, which is on by default, for some TCP services. The purpose of Nagle's algorithm is to reduce the number of small packets sent. The algorithm establishes not sending outgoing data when there is either unacknowledged sent data, or there is less-than-maximum segment size (typically around 1500 bytes for Ethernet) worth of data to be sent. While this algorithm allows for efficient data transmission, there are times when it is desirable to disable it.

delayed_ack=0-1000

The time, in milliseconds, to delay sending ACK packets in response to received data for the specified range of network services. The default is 200 milliseconds.

Setting this option to 0 (zero) sends an ACK packet back acknowledge the received data immediately. Setting it to any other value means that the ACK packet will be sent after the specified time. If the network services generate new data during that time, the ACK packet will be sent along with the data packet.

You can use this setting to avoid congestion and reduce network traffic, However, do not change this option from its default setting unless you have a solid understanding of network services and data transmission, or have been instructed to make the change.

192 Chapter 2 Command Descriptions