ISO 21218:2018 pdf free
ISO 21218:2018 pdf free.Intelligent transport systems – Hybrid communications – Access technology support
The CIs built on different media are using the same ITS-S networking & transport layer. All CIs use the same type of IN-SAP between the ITS-S networking & transport layer and the CAL.
The medium-specific CAL provides an IN-SAP to the ITS-S networking & transport layer.
The CAL can be considered as an access technology (medium)-specific LLC or as an extension of an existing LLC providing the adaptation of the specific needs of an access technology (medium) to the common communication IN-SAP.
The CIs built on different media use the same ITS-S management, applying the functionality specified for the MI-SAP.
The MAE provides the MI-SAP to the ITS-S management following the same principles as outlined in ISO/IEC/IEEE 8802-11[2] with respect to the station management entity. The MI-SAP offers the services presented in Clause 9.
The LocalCIID field identifies uniquely a specific CI in a specific ITS-S communication unit (ITS-SCU) in an instance of an ITS station.
NOTE A two octet ITS-SCU-ID specified in ISO 24102-4[13], identifying uniquely an ITS-SCU of an ITS-SU, can be derived from LocalCIID by means of a look-up table.
The RemoteCIID field identifies a VCI of the CI identified by LocalCIID which connects to a remote ITS-S unit (e.g. MAC unicast communication), or to a group of them (e.g. MAC broadcast or multicast communication). One reserved number of RemoteCIID identifies the CI which is addressed by the value
of LocalCIID. This reserved number shall be
一the distinct null identifier (DNI) presented in D.2 for CIs supporting 48-bit MAC addresses;
一the “VCISerialNumber”field set to zero combined with the “UC/GC” field set to zero presented in D.3 for CIs which do not support 48-bit MAC addresses.
LocalCIID and RemoteCIID are presented in 64-bit global identifier (EUI-64) fields, see D.1, which may contain a 48-bit MAC address as ilustrated in D.2.
For access technologies using 48-bit MAC addresses, LocalCIID may contain the globally unique MAC address of the CI, and RemoteCIID may contain either the individual MAC address reported in a received frame, or broadcast MAC address or a multicast MAC address.
Other access technologies use the numbering scheme specified in D.3.
The 48-bit MAC address is one example of a link layer address. Registered unique link layer addresses are presented in the medium-specific I-Parameter 8 “LLaddress”. Locally assigned temporary values of a link layer address are stored in the I-Parameter 9 “LLaddressTemp”.ISO 21218 pdf download.
