Paradise 205486 REV F - Manual (Page 124)

124 208495 REV C Operations Manual, HPA2, Compact Outdoor SSPA
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 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. Teledyne 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 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 ex-
ample of the UDP frame with encapsulated Teledyne Paradise Datacom protocol frame is
shown on Figure 10-6.
A detailed OSI model for the RM SSPA M&C interface is represented in Table 10-10.
This set of Ethernet IP protocols is currently supported by Teledyne Paradise Datacom Uni-
versal M&C package (Compact Outdoor SSPA). The software is supplied on CD with the unit,
or can be downloaded by registered users from the company web site, http://
www.paradisedata.com.
UDP Header
(8 bytes)
SSPA Serial Protocol Frame
(11+N Bytes, 0<N<128)
Figure 10-6: UDP Redirect Frame Example
CRC 16
checksum
OSI Layer Protocol Notes
Application
Paradise Datacom CO
SSPA Serial Protocol
Frame structure described in Section 10.0
Transport UDP
Connectionless transport service. MTU on target PC
must be set to accommodate largest SSPA Serial Pro-
tocol 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 10-10: OSI Model for Compact Outdoor SSPA Ethernet IP Interface