The main tasks of the Service Discovery Protocol are communicating the availability of functional entities called services in the in-vehicle communication as well as controlling the send behavior of event messages. This allows sending only event messages to receivers requiring them (Publish/Subscribe). The solution described here is also known as SOME/IP-SD (Scalable service-Oriented MiddlewarE over IP - Service Discovery).
This page hosts a formal specification of AUTOSAR SOME/IP Service Discovery using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.
digraph {
rankdir=LR;
node [shape=plaintext];
subgraph cluster__some_ip_sd {
label="SomeIpSd";
graph[style=dotted];
some_ip_sd__seq [label=<<TABLE BORDER="0" CELLBORDER="1" CELLSPACING="0">
<TR><TD BGCOLOR="#E0FFE0">pos</TD><TD BGCOLOR="#E0FFE0">size</TD><TD BGCOLOR="#E0FFE0">type</TD><TD BGCOLOR="#E0FFE0">id</TD></TR>
<TR><TD PORT="flags_pos">0</TD><TD PORT="flags_size">1</TD><TD>SdFlags</TD><TD PORT="flags_type">flags</TD></TR>
<TR><TD PORT="reserved_pos">1</TD><TD PORT="reserved_size">3</TD><TD></TD><TD PORT="reserved_type">reserved</TD></TR>
<TR><TD PORT="len_entries_pos">4</TD><TD PORT="len_entries_size">4</TD><TD>u4be</TD><TD PORT="len_entries_type">len_entries</TD></TR>
<TR><TD PORT="entries_pos">8</TD><TD PORT="entries_size">len_entries</TD><TD>SomeIpSdEntries</TD><TD PORT="entries_type">entries</TD></TR>
<TR><TD PORT="len_options_pos">...</TD><TD PORT="len_options_size">4</TD><TD>u4be</TD><TD PORT="len_options_type">len_options</TD></TR>
<TR><TD PORT="options_pos">...</TD><TD PORT="options_size">len_options</TD><TD>SomeIpSdOptions</TD><TD PORT="options_type">options</TD></TR>
</TABLE>>];
subgraph cluster__sd_flags {
label="SomeIpSd::SdFlags";
graph[style=dotted];
sd_flags__seq [label=<<TABLE BORDER="0" CELLBORDER="1" CELLSPACING="0">
<TR><TD BGCOLOR="#E0FFE0">pos</TD><TD BGCOLOR="#E0FFE0">size</TD><TD BGCOLOR="#E0FFE0">type</TD><TD BGCOLOR="#E0FFE0">id</TD></TR>
<TR><TD PORT="reboot_pos">0</TD><TD PORT="reboot_size">1b</TD><TD>BitsType1(BigBitEndian)</TD><TD PORT="reboot_type">reboot</TD></TR>
<TR><TD PORT="unicast_pos">0:1</TD><TD PORT="unicast_size">1b</TD><TD>BitsType1(BigBitEndian)</TD><TD PORT="unicast_type">unicast</TD></TR>
<TR><TD PORT="initial_data_pos">0:2</TD><TD PORT="initial_data_size">1b</TD><TD>BitsType1(BigBitEndian)</TD><TD PORT="initial_data_type">initial_data</TD></TR>
<TR><TD PORT="reserved_pos">0:3</TD><TD PORT="reserved_size">5b</TD><TD>b5</TD><TD PORT="reserved_type">reserved</TD></TR>
</TABLE>>];
}
}
some_ip_sd__seq:flags_type -> sd_flags__seq [style=bold];
some_ip_sd__seq:len_entries_type -> some_ip_sd__seq:entries_size [color="#404040"];
some_ip_sd__seq:entries_type -> some_ip_sd_entries__seq [style=bold];
some_ip_sd__seq:len_options_type -> some_ip_sd__seq:options_size [color="#404040"];
some_ip_sd__seq:options_type -> some_ip_sd_options__seq [style=bold];
}