Paradise Datacom 4 RU Chassis, Руководство по эксплуатации

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4 RU SSPA Chassis Operations Manual 201627 REV X 99
Teledyne Paradise Datacom provides a Windows
TM
-based control application to
establish UDP-based Ethernet communication with SSPAs. The control application
manages the exchange of datagrams to ensure error-free communication. An attractive
benefit of UDP is that it requires low overhead resulting in minimal impact to network
performance. The control application sends a UDP request to SSPA unit and waits for
response. The length of time the control application waits depends on how it is
configured. If the timeout is reached and the control application has not heard back
from the agent, it assumes the packet was lost and retransmits the request. The
number of the retransmissions is user configurable.
The Teledyne Paradise Datacom RM SSPA Ethernet IP interface can use UDP ports
from 0 to 65553 for sending and receiving. The receiving port needs to be specified
through the front panel menu. For sending, it will use the port from which the UDP
request originated. Of course, it is up to the user to select an appropriate pair of ports
that are not conflicting with standard IP services. Paradise Datacom recommends
usage of ports 1038 and 1039. These ports are not assigned to any known application.
As an application layer protocol (which actually carries meaningful data), the standard
Teledyne Paradise Datacom RM SSPA serial protocol was selected. This protocol
proves to be extremely flexible and efficient. It is also media independent and can be
easily wrapped into another protocol data frame. An example of the UDP frame with
encapsulated Paradise Datacom protocol frame is shown on
Figure 7-10
.
A detailed OSI model for the RM SSPA M&C interface is represented in
Table 7-10
.
UDP Header
(8 bytes)
SSPA Serial Protocol Frame
(11+N Bytes, 0<N<128)
Figure 7-10: UDP Redirect Frame Example
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OSI Layer Protocol Notes
Application
Paradise Datacom RM
SSPA Serial Protocol Frame structure described in
Section 7.1
through
7.6
Transport UDP
Connectionless transport service. MTU on target
PC must be set to accommodate largest SSPA
Serial Protocol Frame. Set MTU to a value larger
than 127 bytes.
Network IP
ARP, RARP and ICMP Ping protocols supported
by RM SSPA controllers. Static IP Address only,
no DHCP support.
Data Link Ethernet 10/100 Base-T Network
Physical
Standard CAT5 (CAT
6) Network Cable
Maximum node length 100 m
Table 7-10: OSI Model for RM SSPA Ethernet IP Interface