Siera Wireless MP555, Software Installation Manual

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MP 555 GPS Software Installation and Configuration Guide
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it 0 will, in future,
)
•
•
)
2130304
Figure 7-3: RNAP Multiplexing layer packet. (Note that B
allow encryption to be enabled and disabled but encryption is not yet
supported.
The header components are:
Header version (four bits)—revision number of the
header. The initial version is 0.
Option bits (four bits)—settings for options. Each bit is
designed to enable/disable an option. Bit 1, Bit 2, and Bit 3
are unassigned and reserved for future use. Bit 0 will, in
future, be used to enable (1) and disable (0) encryption.
(Encryption is not yet supported.)
Header
10 bytes
Message payload
(MTP packet
variable length up to 1400 bytes
Packet layer
At the packet layer, an RNAP packet consists of a two-byte
header followed by the message payload (a multiplexing layer
packet). The header only contains the length of the message
payload..
Header
Message payload
(Packet length)
(Multiplexing layer packet)
2 bytes
variable length up to 1410 bytes
Figure 7-2: RNAP Packet layer packet (the maximum length is 1412 bytes)
Multiplexing layer
At the multiplexing layer, an RNAP packet consists of a
10 byte header followed by the message payload (an MTP
packet). The header has five components.
Header Option Application Unique Mobile Reserved for
version bits
Future Use
Device ID
ID
(32 bits, set to 0)
(4 bits) (4 bits) (8 bits)
(32 bits)
3
Reserved
set to 0
2
Reserved
set to 0
1
Reserved
set to 0
0
Enable
encryption