Symbol PPT 8800, Руководство по продукции

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PPT 8800 Series Product Reference Guide for Embedded Windows
®
CE .NET
The cradle modifies one IP address and port number pair inside a TCP/IP and UDP/IP
packet header. Those packets going to the outside network have their source address
translated to the IP address of the cradle and their source port changed to a unique port
number associated with the cradle slot from which it came. Conversely, packets designated
to the cradle’s private network have their destination IP address and port number mapped
to the equivalent private network IP address and port number. The differences in the port
numbers distinguish between packets for different slots in the cradle. The benefit of both IP
address and port translation is that multiple slots can simultaneously share the one network
IP address of the cradle.
Accessing the outside network with the CRD8800-4000E is not the same as a direct
connection to the outside network. When using NAPT, many network services do not
function at all. Since NAPT modifies addresses in TCP/IP and UDP/IP headers, it is
insufficient for network services that embed IP addresses inside packet data. Also, the
CRD8800-4000E assumes that terminals sending data with one TCP or UDP source port
expects to receive replies on the same port number, but some network services may reply
with data over a range of ports. These network services are unusable with the CRD8800-
4000E. Also, some services listen to incoming requests from the network. Since port
numbers are usually fixed for a given service, no terminals can be set up as listeners.
Note: Turn off NAPT mode before using ActiveSync.
Inter-Connecting Cradles
Up to four 4-slot serial cradles (CRD8800-4000S) may be inter-connected (daisy-chained)
with the CRD8800-4000E. Use the Ethernet RJ-45/10 to RJ-45/10 inter-cradle cable (p/n
170142-001) to connect the CRD8800-40000S to the CRD8800-4000E and use the serial
RJ-45/10 to RJ-45/10 inter-cradle cable (p/n 70349-001) to connect the CRD8800-4000S
to another CRD8800-4000S.
W
ARNING
Each cradle must have its own power supply. Any other
method of power hookup is unsafe.
To inter-connect cradles:
1. Connect the power supply to the second 4-slot cradle.