CalAmp Viper 100, Руководство пользователя

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#9 Viper_SC_Manual_
001-5008-000_Rev12e.docx |
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IP Optimization is only available in router mode.
Figure 44 – IP Optimization (& Tuning)
― RF ACK ( RF Acknowledgements). Select Enabled/Disabled. Default = Disabled . If enabled , the receiving Viper will reply
with an acknowledgement message to the sending Viper to indicate that it has received the packet successfully. If the
sending Viper does not receive the acknowledgement, it assumes the message was lost and resends the message. This
number of retries is specified using MAC Retries (
Section 4.4.1) and OIP Retries (below).
TCP packets are always retried regardless of the RF ACK parameter (unless OIP Retries is set to 0). Other types of packets
are only retried if RF ACK is enabled.
― TCP Proxy. The TCP proxy optimizes the throughput of a TCP connection by removing some of the TCP packets from the
Airlink. A Viper SC receiving a TCP packet over the air sends an RF acknowledgment to the sending unit. If the sending
Viper SC receives the RF acknowledgement, it knows the packet made it across the Airlink successfully. When the TCP
proxy is enabled and the TCP packet contained data, the sending Viper SC immediately generates a TCP ACK to the
sending host (RTU, PLC, PC, etc). When the destination host receives the TCP packet, it generates a TCP ACK back to the
source. This TCP ACK is captured by the Viper SC and is not sent over the Airlink.
Figure 45 – TCP Proxy
In this example, the following events occur in this order: