Datalogic DL Cordless Card Reference Manual page 30

4
Case 3 – DLCC as Client / Server
Client
HOST 1
Both DLCCs are able to communicate bi-directionally. For analysis purposes only, we
assume the situation where Host 1 is Client and Host 2 is Server. It is clear that the
situation is analogous in the opposite direction:
•
If DLCC 1 -
The Client, (Host 1) sends a message to the Remote Host (Host 2), but no
control exists upon reception and even if ACK/NACK Protocol is implemented on
the Server side (Remote Host), no answer is returned from DLCC 2 to DLCC 1.
This is not a secure communication.
•
If DLCC 1 -
The Client, (Host 1) sends a message to the Remote Host (Host 2). DLCC 2
acknowledges good radio reception but no control is made on Remote Host
reception. If DLCC 2 acknowledges radio reception within the Radio Protocol
Timeout, DLCC 1 sends ACK to its local Host, otherwise it sends NACK.
18
Figure 7 – DLCC as Client / Server
Transmission Mode = 1 way
ACK/NACK from Remote Host = disabled
FIFO = enabled
Handshaking = any
Transmission Mode = 1 way
ACK/NACK from Remote Host = enabled
FIFO = enabled
Handshaking = any
DL CORDLESS CARD™
Server
HOST 2