DE102015209361A1 - Packet-based communication network with autoconfiguration of local network addresses - Google Patents

Abstract

The invention relates to a packet-based communication network with a data link layer and a network layer, in particular such a vehicle on-board network, in which locally administered network addresses, in particular media access control (MAC) addresses, are used for the data link layer. In addition to such a communication network, various aspects of the invention relate in particular to an address administration device, a subscriber and a packet switching device therefor as well as to a vehicle having such a communication network. A subscriber can be added to the communication network even if its local backup layer address is not yet known. This is assigned to it by the address administration device to a special request message and based on a known connection information, which may be a network layer address of the subscriber or a virtual local area network (VLAN) tag in particular, purposefully communicated to the requesting participants.

Description

The present invention relates to a packet-based communication network, in particular such a vehicle electrical system. In this case, the communication takes place, in particular, by means of a data link layer ("Layer 2") and a network layer (Layer 3) according to the known OSI / ISO reference model and in the data link layer locally administered network addresses, in particular " Media Access Control (MAC) "addresses are used. In particular, various aspects of the invention relate, besides such a communication network, to an address administration device, a subscriber (i.e., a subscriber device) and a packet switching device therefor, as well as a vehicle having such a communication network.

With the advancement of electronics, control and communication technology, many types of vehicles, particularly automobiles, have evolved from purely mechanical or electromechanical equipment to systems in which there are usually a variety of control devices including multimedia and infotainment devices. These devices usually communicate with each other. In particular bus systems are known for the implementation of such communication connections, such as, for example, those according to the CAN (Controller Area Network), Standard (ISO 11898) or the MOST - Media Oriented Systems Transport - de facto standard (defined by the "MOST co-operation") for multimedia and infotainment networks in the automotive industry.

In addition, other communication network technologies are known from the field of computer technology and network technology, in particular Ethernet (standardized, in particular, as IEEE 802.3 with corresponding sub-standards) and the Internet underlying communication using Internet Protocol (IP) data packets.

Meanwhile, the use of Ethernet-based communication technology has also found its way into vehicles. An example of this is the "SOME / IP" communication protocol developed by a consortium of vehicle manufacturers, including "SOME / IP Service Discovery", which was also included in the AUTOSAR standard and a solution for IP-over-Ethernet-based on-board network communication specified in the vehicle. In this case, IP packets (layer 3 in the OSI / ISO reference model) are transmitted in the sense of IP-over-Ethernet communication by means of Ethernet communication (layer 2 according to the OSI / ISO reference model). The Ethernet communication on the data link layer (layer 2 in the OSI / ISO reference model) is regulated by a corresponding network addressing, which may be in particular a so-called "MAC" addressing. The MAC address (Media Access Control Address) is the hardware address of each individual network adapter (network interface of a device), which serves as a unique identifier of the device in a computer or communication network. Other common names are "Ethernet ID" and "Physical Address". There are also a number of company-specific names.

For communication networks in which the communication takes place between subscribers both on the data link layer and the network layer, in particular in the case of IP-over-Ethernet communication networks, the "Address Resolution Protocol (ARP)" is known as the network protocol that corresponds to the network address of the network layer Determined address of the data link layer and this assignment if necessary put down in the so-called ARP tables of participating participants (see. Internet standard RFC 826 ). It is used in particular in connection with IPv4 addressing in Ethernet networks to determine MAC addresses to given IP addresses ("IPv4" stands for Internet Protocol version 4 according to Internet standard RFC 791 ).

In addition, it is known (cf. Standard IEEE 802.1q ), a local area network (LAN) into several logical subnets (so-called Virtual Local Area Networks, VLAN) to divide. In doing so, the physical LAN is split into multiple VLANs so that VLAN-aware switches do not route the data packets of one VLAN to another VLAN, even if the subnets can be connected to a common switch. The differentiation of the different VLANs can be done in particular by means of so-called "tagged" VLANs, which are markings which are added to the data packets of a VLAN in order to indicate their affiliation with the corresponding VLAN.

An Ethernet MAC address includes 48 bits each for sender and receiver. and is, in a common representation as in 1 shown, structured. Thus, the MAC address consists of 6 bytes or bit octets. Starting with the most significant octet (MSB, 1st octet), the first three octets form a first block. The 1st octet contains in particular two 1-bit flags, which are referred to as "I / G" flag and "U / L" flag, respectively. The U / L flag controls whether the respective message is a unicast message (U / L = '0') in which the destination of the message is a single user, or a multicast or multicast message Broadcast message (U / L = '1') in which the message is addressed to several or all subscribers at the same time. The I / G flag, on the other hand, controls whether the Ethernet MAC address is a global unique (I / G = '0') or a locally administered Ethernet MAC address (I / G = '1'). In this case, a globally unique Ethernet MAC address is a globally unique address in which the 22 bits of the first block remaining after deduction of the two mentioned flags form an identifier, the so-called "Organizationally Unique Identifier (OUI)" clearly identifies a company or organization assigning the Ethernet MAC address. The block formed from the second three octets represents a second assigned by this company or organization unique identifier (Network Interface Controller (NIC)) specific to an associated data link layer connection, for example in the form of a serial number of the backup layer capable device. In contrast, the 46 bits (ie all bits except the two flags) of a locally administered Ethernet MAC address of a device can be freely selected, since this is defined only within a local network (eg LAN). Within this local network, however, the locally administered Ethernet MAC address must be unique. In contrast, to communicate with the device outside of this local area network, a router with a globally unique Ethernet MAC address is required, which then performs an address conversion where the subscriber's local MAC address in the router is represented by the router's unique global source address is replaced so that the subscriber can communicate with the world via the router. The transmission can either be arranged or configured in the communication network in such a way that it can be combined with the least significant bit (LSB, right in FIG 1 ) or the most significant bit (MSB, left in 1 ) begins. The first case is usually referred to as a "canonical representation" and the second case as a "bit-reversed" representation.

Typically, most Ethernet-enabled devices are given a globally unique address so they can communicate with the outside world without going through a router and its Ethernet MAC address. The same applies in particular to Ethernet-capable control devices of vehicles, in particular of motor vehicles. However, the available address space for globally unique addresses is currently limited, and it is expected that the allocation of these addresses will be more stringently regulated in the future to delay exhaustion of this address space as long as possible. Accordingly, it can also be assumed that in Ethernet-based communication networks, in particular in such vehicle on-board networks, increasingly also locally administered Ethernet MAC addresses are used.

However, the use of local administered network addresses, in particular MAC addresses (in the case of Ethernet or other data link layer technologies or protocols) also entails some problems, since in particular devices of the same design can have the same network address at the factory and thus not easily be distinguished as different participants of a communication network at the level of the link layer. Especially in a vehicle electrical system such subscribers can be regularly control devices, such as identical cameras, so that these or their spatial arrangement on the vehicle can no longer be easily distinguished by the factory-issued network address. In addition, when installing or replacing a subscriber, in particular a control unit in a vehicle, it may be necessary to reprogram the local network address to achieve a clear addressing, which means additional expense.

Against this background, the present invention seeks to provide a packet-based communication network with a link layer and a network layer, in which the discrimination of different participants is improved when using locally administered network addresses.

A solution to this problem is achieved according to the teaching of the independent claims by an address administration device according to claim 1, a subscriber (ie a subscriber device) according to claim 8, a packet switching device according to claim 10, a communication system according to claim 13, respectively for a packet-based communication network with a data link layer and a network layer, and a vehicle according to claim 15 with such a communication system.

Various embodiments and modifications of the invention are subject of the dependent claims.

A first aspect of the invention relates to an address administration device for a packet-based communication network with a data link layer and a network layer, in particular for such a vehicle on-board network. The address administration device has a data link interface for connection to a packet-based communication network and an address allocation unit. The address assignment unit is configured to receive via the link layer interface a message of a subscriber in the communication network containing connection information regarding the subscriber and an address request identifier, and to check, based on the address request identifier, whether the message is a login message. Of Further, the address assignment unit is configured if, according to the test, it is a sign-on message to assign a local link layer network address to the subscriber and to send a broadcast message via the link layer interface into the communication network which assigns that assigned link layer network address. Contains address and the connection information regarding the subscriber.

A "vehicle electrical system" in the sense of the invention means the entirety of all electrical components connected to one another in communication in vehicles, in particular in motor vehicles. Thus, in particular a packet-based communication network for vehicles with control units of the vehicle as participants, a vehicle electrical system in the context of the invention.

An "address administration device" in the sense of the invention is to be understood as a component of a packet-based communication network which serves the administration, in particular the allocation of network addresses to nodes of the communication network, for example to subscribers. In particular, the address administration device can be designed centrally for the entire communication network or else only for a subnetwork thereof for the address administration of addresses with respect to one or more layers of the OSI / ISO reference model.

The terms "link layer" or "network layer" refer to Layer 2 (Data Link Layer) or Layer 3 (Network Layer) of the known OSI / ISO reference model and represent common German designations for these layers. The MAC addressing is Part of the link layer. Known protocols for Layer 2 are Ethernet (which also includes Physical Layer 1) and Layer 3 Internet Protocol (IP). Further representatives for protocols and standards for layer 2 are in particular: IEEE 802.11 (WIRELESS INTERNET ACCESS), IEEE 802.4 (Token bus), IEEE 802.5 (Token ring), FDDI, HDLC, SDLC, DDCMP, IEEE 802.2 (LLC), ARP, RARP, STP, and Shortest Path Bridging; and to layer 3: X.25, ISO 8208 . ISO 8473 (CLNP), ISO 9542 (ESIS), IPsec, and ICMP.

A "link layer interface" in the sense of the invention is to be understood as a communication interface at the level of the data link layer for the exchange of data, wherein this communication interface has a link layer address and can be addressed via it. In this case, a communication interface is a technical entity, in particular a control system, by means of which a communication connection with at least one other technical entity can be provided directly or indirectly via at least one interposed communication device (for example a radio interface or a gateway). In particular, a communication interface can be given physically by a connection device to an electrically conductive or optical or wireless connection. In addition, the communication interface may include means for data processing or processing, by means of which data or other information can be transmitted on the transmitter side in a predetermined manner or processed at the receiving end. This can be done in particular by means of so-called communication protocols. Data link interfaces are also regularly referred to as "network adapters", especially in Ethernet networks.

A "connection information with respect to the subscriber", or "connection information" in the sense of the invention, is to be understood as information which can be transmitted by means of a message in the communication network, in particular in the form of a bit sequence, and the at least one component or subset of an addressing or identifier by means of which the subscriber is identifiable in the communication network.

An "address request identifier" in the sense of the invention is to be understood as meaning information, in particular a characteristic feature, character or a group of characteristic features or characters for unambiguously identifying whether a message containing the address request identifier is a sign-on message. A "notification message" within the meaning of the invention is a message with which the subscriber sending it in the communication network, in particular with respect to the address administration device, signals that its data link layer network address should be reconfigured.

By "configured" in the sense of the invention is to be understood that the corresponding device is already set up or adjustable - i. configurable - is to fulfill a specific function. The configuration can take place, for example, via a corresponding setting of parameters of a process sequence or of switches or the like for activating or deactivating functionalities or settings.

By means of the address administration device, an address management in the communication network can be provided which is triggered upon initial startup, restart after a reset, after the exchange of a subscriber or after the addition of a new subscriber via a corresponding message from one or more subscribers performs automatic address reallocation for the locally administered link layer addresses of these subscribers.

In the following, preferred embodiments of the address administration device and their developments will be described, which, unless expressly excluded, may be combined as desired with one another as well as with the other aspects of the invention described below.

According to a first preferred embodiment, which can likewise be applied to the other aspects of the invention mentioned below, the known Internet Protocol (IP) is used as the communication technology for the network layer. Thus, an IP-over-packet technology is used. According to a preferred variant of this embodiment, Ethernet is used as the technology for the data link layer underlying the network layer, so that an IP-over-Ethernet communication is used in the communications network and, in particular, the address administration device supports it.

According to a preferred embodiment, the connection information is a network layer address of the subscriber, which may in particular be an IP address. This is advantageous in particular if the subscriber already knows his network layer address and sends it together with the login message or as part of it to the address administration device. The broadcast message of the address administration device then also contains this network layer address of the subscriber, so that all recipients of the broadcast message can use this to decide whether the message is intended for them or not. Thus, despite the use of a broadcast message, the response of the address administration device can reach the correct subscriber with pinpoint accuracy, since the latter can recognize from the connection information that the message is addressed to him. From the broadcast message, he can then extract and store the link layer network address newly assigned to him by the address administration device to use for future communication.

According to another preferred embodiment, the connection information is a VLAN tag of a VLAN uniquely assigned to it within the communication network. This is particularly advantageous if the registering subscriber also does not know his network layer address in the communication network and therefore can not communicate it because it has not yet been defined or assigned at the factory, for example. In order nevertheless to allow a clear addressing for the response of the address administration device by broadcast message, the communication network can be divided into different VLANs, the different participants can be distinguished by their affiliation to different VLANs, even if they initially have no or the same, in particular, have a preliminary link layer MAC address or network layer address. This can be the case especially for identical participants. The address administration device accordingly removes the VLAN tag of a logon message that arrives at it and inserts it into the response sent as a broadcast message such that one or more packet switching devices located between the address administration device and the subscriber are able to use the VLAN tag. Tags to forward the response purposefully to the participant.

According to a further preferred embodiment, the address assignment unit is further configured, if the check is a login message, also assigning the subscriber a network layer address and sending it by means of the broadcast message. In this way it is possible, by means of the address administration device, to supply a subscriber with his network address both at the security layer level and at the network layer level. This is particularly advantageous if the subscriber does not have his own network layer address, or this is to be changed later.

According to another preferred embodiment, the address request identifier is a special predetermined link layer network address. This can be advantageous, in particular, when the message format of the login message regularly has a user data field which is configured to transmit link layer network addresses (this is the case in particular in the case of the ARP protocol). The address administration device can then extract from an received message the content of this field whose position within the message format is known in advance or can be easily determined. By means of a simple comparison, the address administration device can then determine whether the content of the field or the link layer network address used as an address request identifier corresponds to the predetermined specific address and thus identifies a login message.

According to another preferred embodiment, the message of the subscriber, the Broadcast message of the address assignment unit, or both formatted according to the ARP protocol format. This can be particularly advantageously used to achieve a particularly efficient implementation of the invention, such as in terms of programming effort or the required storage space in the case of a corresponding software implementation, since the ARP protocol, especially in IP over Ethernet networks, often is regularly implemented and can be reused for the purposes of the invention with a corresponding extension or adaptation.

According to a preferred variant of this embodiment, the address administration device may define the address request identifier characterizing a login message as a dedicated link layer network address; the check checks to see if the subscriber's message specifies this particular link layer network address in the source MAC address field according to the ARP protocol format. Furthermore, the broadcast message of the address assignment unit may include in the MAC source address field in accordance with the ARP protocol format the link layer network address assigned to the subscriber. In particular, in the field of the network-layer destination address according to the ARP protocol format, the broadcast message of the address allocation unit may contain a network-layer address of the subscriber. The network layer address can be changed or reassigned by the address administration device if necessary, or otherwise remain unchanged and thus correspond to the network layer address already contained in the login message.

A second aspect of the invention relates to a subscriber for a packet-based communication network with a data link layer and a network layer, in particular for such a vehicle on-board network. The subscriber has a link layer interface for connection to a link layer / network layer communication network and a communication unit. The communication unit is configured to send a message via the link layer interface to an address administration device of the communication network, the message including a special address request identifier identifying the message as a login message. Furthermore, the communication unit is configured to receive a subsequent broadcast message from the address administration device and extract therefrom a link layer network address assigned to the subscriber by the latter and to take over as a link layer network address of the subscriber. In this way, the subscriber is enabled, on the one hand, to request a new link layer network address from the address administration device and, on the other hand, to retrieve the corresponding new address assigned to him from the reply sent as a broadcast message and for his future communication within the communication network to use.

According to a preferred embodiment, the communication unit is further configured to extract from the broadcast message of the address administration device a network layer address assigned to the subscriber by the latter, and to adopt it as a network layer address of the subscriber. In this way, in addition to the link layer network address, a network layer address can first be requested by the address administration device and then taken from its reply.

With respect to the format of the application message or the broadcast message of the address administration device, according to the interaction of the participant with the latter, the embodiments and variants already described above for the first aspect of the invention represent preferred implementation possibilities.

A third aspect of the invention relates to a packet switching apparatus for a packet-based communication network with a data link layer and a network layer, in particular for such a vehicle on-board network. The packet switching apparatus has a plurality of link layer interfaces for connection to subscribers and an address administration device of a link layer / network layer communication network and a switching unit. The switching unit is configured to uniquely assign a VLAN to each of the link layer interfaces, to receive at one of the link layer interfaces a broadcast message from the address administration device, to recognize a VLAN tag contained in the broadcast message, and the broadcast message based thereon to selectively route only one of the link layer interfaces to a subscriber associated with a VLAN identified by the recognized VLAN tag.

The packet switching device, which according to a preferred variant when using Ethernet as a link layer technology can be in particular an Ethernet switch, is thus to be considered in connection with the embodiments of the first aspect of the invention, which also use VLANs. The assignment of subscribers to a respective VLAN takes place in accordance with the data link layer Interface of the packet switching device, via which the respective subscriber is connected to this. In this way, the broadcast message of the address administration device can be delivered accurately to the requesting a new address subscriber even if he could identify in his login message neither through its own link layer network address nor through its network layer address.

In a preferred embodiment, the packet switching unit is further configured to receive a message from a subscriber at a first of the data link interfaces and to add to the message a VLAN tag which identifies a VLAN uniquely assigned to the first data link interface and add it to the VLAN tag supplemented message via another of the link layer interfaces to the address administration device to send. In particular, the packet switching unit may be configured such that any received message that does not have a VLAN tag is forwarded to the address administration device. The subscriber must therefore also have no knowledge of which VLAN he is assigned. The assignment by means of VLAN tagging is carried out for the application of a subscriber only at a lying on the connection between the subscriber and the address administration device packet switching device on the basis of the link layer interface to which the subscriber is connected to the packet switching device.

According to yet another preferred embodiment, the switching unit is further configured to check the message received from the subscriber to see if it contains a network layer address of the subscriber as connection information to selectively add the VLAN tag to the message only if not the case is. Furthermore, according to this embodiment, the switching unit is configured to check the broadcast message as to whether it contains a network layer address of the subscriber as connection information, and if this is the case, to forward the broadcast message as a broadcast message into the communication network; and if not, selectively forward the broadcast message to the subscriber via only one of its data link interfaces associated with a VLAN identified by a VLAN tag contained in the broadcast message. In this way, VLAN tagging can be selectively used to come into effect only if an identification of the subscriber via his network layer address is not available. Thus, mixed solutions can also be implemented in which network layer addresses and partially VLAN tagging are used for the identification of subscribers in the context of an address assignment.

A fourth aspect of the invention relates to a communication system for a packet-based communication network with a link layer and a network layer. The communication system has an address administration device according to the first aspect of the invention, in particular according to one of its embodiments, and a plurality of subscribers according to the second aspect and invention, in particular according to one of its embodiments.

According to a preferred embodiment, the communication system further comprises a packet switching device according to the third aspect of the invention, in particular according to one of its embodiments.

Thus, overall, there is a communication system including the address administration device according to the first aspect of the invention, a plurality of users according to the second aspect of the invention, and optionally one or more packet switching devices according to the third aspect of the invention as components that can cooperate to produce the above to solve this task. The communication system according to the invention can be used particularly advantageously in the context of a vehicle electrical system.

Accordingly, a fifth aspect of the invention relates to a vehicle, in particular a motor vehicle, with a communication system according to the fourth aspect of the invention.

Further advantages, features and possible applications of the present invention will become apparent from the following detailed description taken in conjunction with the figures.

Show

1 schematically the structure of an Ethernet MAC address according to the prior art;

2 the procedure for address assignment according to the known from the prior art ARP protocol for determining the MAC address of the data link layer to a network address of the network layer in a simple exemplary communication network and the addressing used for this purpose;

3 schematically the structure of a communication network in the form of a vehicle electrical system, according to preferred embodiments of the invention;

4 schematically illustrates an exemplary sequence of an address assignment in the communication system 3 using an IP address of the subscriber as connection information, as well as the addressing used for this purpose; and

5 schematically illustrates an exemplary sequence of an address assignment in the communication system 3 using a VLAN tag as connection information, as well as the addressing used.

The structure of an Ethernet MAC address according to 1 was previously described. In the following, using the 2 . 4 and 5 By way of example, the IP protocol according to its version 4 (IPv4) is used on the network layer in each case. However, this is not limiting. Just as well, other technologies may be used for the network layer in other preferred embodiments, especially other versions of IP such as IPv6.

First, it will open 2 With reference to which the address assignment according to the ARP protocol is to be exemplified. This serves as a starting point for explaining preferred embodiments of the present invention. For this, consider a simple exemplary IP over Ethernet network that uses an Ethernet switch 3 three participants 2 . 4 respectively. 5 are connected. Attendees 5 now would like a message to the participant 2 but does not know its MAC address, but only its IP address. Attendees 5 therefore sends an address request message R according to the ARP protocol in the network. The table 2 shows the addressing used. The message is sent out as a broadcast message (Type = BC). Accordingly, for the link layer level addressing, the MAC address MAC-5 of the subscriber becomes the MAC source address (SRC) 5 as well as the MAC destination address (DST) the MAC address MAC-BCST intended for broadcast messages network-wide (this usually has the numerical value FF: FF: FF: FF: FF: FF). According to the ARP protocol, the message contains four fields called MAC source, MAC destination, IP source and IP destination. The MAC source field specifies the MAC address MAC-5 of the sending participant 5 and the MAC destination field specifies the MAC-BCST broadcast address, but in alternative embodiments, the zero value 0.0.0.0 may instead be provided in this field. at. Accordingly, the respective IP address IP-5 of the sender can be found in the IP source and IP destination fields (subscribers 5 ) or respectively IP-2 of the desired recipient (subscriber 2 ) again. At the switch 3 the message R is duplicated and in each case to all other participants 2 and 4 forwarded to the network.

The recipients of the message R check in each case whether the specified IP destination address matches their own IP address. If this is the case, they respond with another message A. Otherwise, discard the received message R. In the example, the participant recognizes 2 that matches its IP address with the IP destination address specified in message R, and thus it sends back a reply message A. Attendees 4 on the other hand, the received message rejects R, since it does not concern him. In the answer A gives the participant 2 in the field MAC source now its own known him MAC address MAC-2, and sends the message as unicast message (type = UC) directly to the subscriber 5 back. This is possible so that it does not require a broadcast message as the MAC address of the subscriber 5 yes in the message R in the MAC Source field. Of the participants 5 now receives from the message A the missing him MAC address of the participant 2 and thus can subsequently communicate with it directly via unicast messages using the respective MAC addresses (see Messages M1 and M2, respectively). The ARP protocol is no longer needed for such subsequent messages.

Now it will open 3 Reference is made schematically in the structure of a communication network in the form of a vehicle electrical system of a motor vehicle F according to preferred embodiments of the invention is shown. For better comparability, the structure was out 2 taken over, so that in the vehicle electrical system, a communication system 1 with a switch 3 and two associated participants 2 . 4 and 5 are provided, which may be in particular control devices of the vehicle. Of the participants 2 is also an address administration device of the communication system. The communication network is again an IP over Ethernet network. Each of the participants 2 . 4 and 5 has a link layer interface 2 B . 4b respectively. 5b as well as via a communication unit 2a . 4a respectively. 5a , which in each case communicates with the associated data link interface. The communication unit 2a the address administration device 2 is also an address assignment unit. The Ethernet switch 3 provides a packet switching device with a switching unit 3a at the link layer level and is via its corresponding link layer interfaces 3b . 3c respectively. 3d with the participants 2 . 4 and 5 connected. In particular, the subscribers may also be sensors, such as cameras, parking distance sensors (PDC), temperature sensors, air pressure sensors or any other vehicle sensors or actuators.

In 4 According to a first preferred embodiment of the invention, an exemplary sequence of an address assignment in the communication system 3 using an IP address of a subscriber as connection information, as well as the addressing used for this purpose. It is assumed that the participant 5 is newly inserted into the communication network and it is not yet assigned a local link layer network address. Attendees 5 Thus, it is not yet able to communicate with other nodes in the network in a conventional way via Ethernet MAC addressing. The assignment of network addresses to the participant 5 takes place by means of a modified form of the ARP protocol. To do this, participants send 5 first again a request message as a broadcast message R (type = BC) in the communication network. However, since he does not yet know his own MAC address, he can not specify it in message R. Instead, it fills in the SRC and MAC Source fields with a special MAC address MAC-A, defined network-wide as an address request identifier. Since the message R is also not addressed to a specific known receiver, the zero value 0.0.0.0 is entered in the IP destination field. In the IP Source field, the participant indicates 5 his, for example, by factory assignment known IP address IP-5.

At the switch 3 the message R is multiplied again and to all other participants 2 and 4 forwarded to the network. Of the participants 2 plays in the network a special role, because it is designed as an address administration device and in particular provided for the allocation of new MAC addresses within the network and adapted. If the address administration device 2 the message R, it recognizes, based on the address request identifier MAC-A contained therein, that it is an address request message while subscriber 4 rejects the message R going to him due to a lack of responsibility for the address administration. The address administration device 2 then sends a message A message again as a broadcast message (type = BC), but in the field IP destination of the participants 5 is identified as a receiver by means of its serving as connection information IP address IP-5. In the MAC source field, however, the MAC address of the sender (ie MAC-2) is not found as usual, but instead that of the subscriber 5 reassigned MAC address MAC-5 on the request message R out.

At the switch 3 the message A is multiplied again and sent to all other participants 4 and 5 forwarded. Of the participants 4 by checking the connection information in the IP Destination field, detects that the message is not intended for it and discards it. Of the participants 5 however, on the basis of such a check, it recognizes that in the IP destination field its own IP address is as connection information, and therefore the message A is addressed to itself. From the MAC source field, he then removes the MAC address MAC-5 newly assigned to him and accepts it as his own and can thus subsequently communicate directly by means of this via unicast messages using the respective MAC addresses (see Messages M1 resp M2). As far as the MAC address of the recipient (here specifically for message M1, the MAC address of subscriber 4 ) is not yet known to the sender, this can be determined via the regular ARP protocol. Thereafter, the ARP protocol is no longer needed for such subsequent unicast messages.

In 5 According to a second preferred embodiment of the invention, an exemplary sequence of an address assignment in the communication system 3 using a VLAN tag as connection information, as well as the addressing used. This variant of the invention can be advantageously used in particular if the IP address of the requesting subscriber is not initially aware of this itself. The local area network, which in turn is an IP over Ethernet communication network, is in this case configured to have multiple VLANs that can be distinguished by corresponding VLAN tagging in the messages. In the example is the participant 4 the VLAN V1 and the participant 5 assigned to the VLAN V2. The address administration device 2 is assigned to all defined VLANs. In addition, there is a VLAN V49 to which all participants are assigned. Again became participant 5 new added. He knows neither his MAC address nor his IP address. Attendees 5 now sends an address request message R5 as a broadcast message (type = BC) in the network. This message does not contain a VLAN tag, because the participant 5 is his affiliation to VLANs unknown. As the participant 5 even his IP address is not known, in the message R5 not just like in 4 the IP destination field but also the IP source field with the zero value "0.0.0.0". The fields SRC and MAC source of the message R again contain the special address request identifier MAC-A.

On the Ethernet switch 3 that the assignment of at its interfaces 3b to 3d Connected individual subscriber to the different VLANs, the message R5 is added a VLAN tag for the VLAN V1 (Type = BCT), before being forwarded as message R5-V1. The address administration device 2 in turn recognizes the address request message R5-V1 as such based on the address request identifier MAC-A contained therein, and sends as in the case of 4 a corresponding response message A5-V1 back, but carries the day of the VLAN V1 as connection information. In the field MAC source is again the participant 5 from the address administration device 2 reassigned MAC address MAC-5 included. In addition, in the IP destination field, the subscriber is the one 5 from the address administration device 2 also reassigned IP address IP-5 included. At the switch 3 is removed from the message A5-V1 of the pointing to the VLAN V1 tag, so that the otherwise unchanged message A5 results that the subscriber 5 is forwarded. The switch recognizes this 3 based on the connection information VLAN tag, to which VLAN the message is addressed. About the well-known physical interface assignment on the switch 3 Based on the different VLANs, the right interface is based on this 3c selected for forwarding the message A5, without causing ambiguities and thus message collision. Of the participants 5 then the received message A5 takes its newly assigned MAC and IP addresses, accepts them as its own and then uses them for subsequent communication.

In the same way become the further participant 4 assigned by means of appropriate messages R4, R4-V2, A4-V2 its MAC and IP addresses. Once and to the extent that the participants know their addresses, you can communicate with each other using their MAC addresses, in particular using unicast messages (type = UC). This is also possible across VLANs via the common VLAN V49 (compare exemplary messages M1-V49, M2-V49, M3-V49).

While at least one exemplary embodiment has been described above, it should be understood that a large number of variations exist. It should also be understood that the described exemplary embodiments are nonlimiting examples only and are not intended to thereby limit the scope, applicability, or configuration of the devices and methods described herein. Rather, the foregoing description will provide those skilled in the art with guidance for implementing at least one example embodiment, it being understood that various changes in the operation and arrangement of the elements described in an exemplary embodiment may be made without departing from the scope of the appended claims deviated from, and its legal equivalents.

LIST OF REFERENCE NUMBERS

F

 vehicle

1

 communication system

2

 Subscriber, in particular at the same time address administration device

2a

Communication unit, in particular at the same time address allocation unit

2 B

Data link interface of the subscriber 2

3

 Packet switching device, in particular Ethernet switch

3a

switching unit

3b-d

Data link interface of the packet switching device

4.5

Attendees

4a, 5a

Communication unit of the respective subscriber 4 respectively. 5

4b, 5b

Data link interface of the respective subscriber 4 respectively. 5

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited non-patent literature

• Standard (ISO 11898) [0002]
• IEEE 802.3 [0003]
• Internet standard RFC 826 [0005]
• Internet standard RFC 791 [0005]
• Standard IEEE 802.1q [0006]
• IEEE 802.11 [0016]
• IEEE 802.4 [0016]
• IEEE 802.5 [0016]
• IEEE 802.2 [0016]
• ISO 8208 [0016]
• ISO 8473 [0016]
• ISO 9542 [0016]

Claims (15)

Address Administration Device ( 2 ) for a packet-based communication network with a data link layer and a network layer, in particular for such a vehicle on-board network, comprising: a data link interface ( 2 B ) for connection to a packet-based communication network; and an address assignment unit ( 2a ) that is configured: via the link layer interface ( 2 B ) a message from a participant ( 4 . 5 ) in the communication network, which contains connection information relating to the subscriber ( 4 . 5 ) and an address request identifier; check, on the basis of the address request identifier, whether the message is a sign-on message; and if, according to the examination, it is a notification message, the participant ( 4 . 5 ) assign a local link layer network address and through the link layer interface ( 2 B ) to send a broadcast message in the communication network, which this assigned link layer network address and the connection information with respect to the subscriber ( 4 . 5 ) contains. Address Administration Device ( 2 ) according to claim 1, wherein the connection information is a network layer address of the subscriber ( 4 . 5 ) or a VLAN tag of a VLAN uniquely assigned to it within the communication network. Address Administration Device ( 2 ) according to one of the preceding claims, wherein the address allocation unit ( 2a ) is further configured: if, according to the check, it is a sign-on message, the subscriber ( 4 . 5 ) also assign a network layer address and send it via the broadcast message. Address Administration Device ( 2 ) according to any one of the preceding claims, wherein the message of the subscriber ( 4 . 5 ) the broadcast message of the address assignment unit ( 2a ), or both are formatted according to the ARP protocol format. Address Administration Device ( 2 ) according to claim 4, wherein the address request identifier characterizing a login message is defined as a special link layer network address and checking is made in the message of the subscriber ( 4 . 5 ) this particular link layer network address is specified in the field of the source MAC address according to the ARP protocol format. Address Administration Device ( 2 ) according to claim 4 or 5, wherein the broadcast message of the address assignment unit ( 2a ) in the field of the MAC source address according to the ARP protocol format that the subscriber ( 4 . 5 ) contains the assigned link layer network address. Address Administration Device ( 2 ) according to claim 4 to 6, wherein the broadcast message of the address assignment unit ( 2a ) in the network layer destination address field according to the ARP protocol format, a network layer address of the subscriber ( 4 . 5 ) contains. Attendees ( 4 . 5 ) for a packet-based communication network with a data link layer and a network layer, in particular for such a vehicle on-board network, comprising: a data link interface ( 4b . 5b ) for connection to a link layer / network layer communication network; and a communication unit ( 4a . 5a ) that is configured: via the link layer interface ( 4b . 5b ) a message to an address administration device ( 2 ) of the communication network, the message including a special address request identifier identifying the message as a login message; a subsequent broadcast message from the address administration device ( 2 ) and from this a subscriber ( 4 . 5 ) from this assigned link layer network address and to take over as a link layer network address of the subscriber. Attendees ( 4 . 5 ) according to claim 8, wherein the communication unit ( 4a . 5a ) is further configured from the broadcast message of the address administration device ( 2 ) one the participant ( 4 . 5 ) from this assigned network layer address and as a network layer address of the subscriber ( 4 . 5 ) to take over. Packet switching device ( 3 ) for a packet-based communication network with a data link layer and a network layer, in particular for such a vehicle on-board network, comprising: a plurality of data link interfaces ( 3a . 3b . 3c ) to connect with participants ( 4 . 5 ) and an address administration device ( 2 a link layer / network layer communication network; and a switching unit ( 3a ) that is configured to use the link layer interfaces ( 3a . 3b . 3c ) uniquely assign a VLAN at one of the data link interfaces ( 3a . 3b . 3c ) a broadcast message of the address administration device ( 2 ) to receive one in the broadcast message to detect the VLAN tag contained in it, and based on this the broadcast message can be selectively accessed only via one of the data link interfaces ( 3b . 3c ) to a participant ( 4 . 5 ) associated with a VLAN identified by the recognized VLAN tag. Packet switching device ( 3 ) according to claim 10, wherein the switching unit ( 3a ) is further configured to connect to a first one of the data link interfaces ( 3b . 3c ) a message from a participant ( 4 . 5 ) and to add to the message a VLAN tag which is one of the first data link interface ( 3b . 3c ) uniquely assigned VLAN and this message supplemented by the VLAN tag via another of the data link interfaces ( 3a ) to the address administration device ( 2 ) to send. Packet switching device ( 3 ) according to claim 11, wherein the switching unit ( 3a ) is further configured: that of the subscriber ( 4 . 5 ) to check whether it contains a network layer address of the subscriber as connection information to selectively add the VLAN tag to the message only if this is not the case; check the broadcast message to see if it has a network layer address of the subscriber ( 4 . 5 ) as connection information; and if so, forwarding the broadcast message as a broadcast message to the communication network; and if not, the broadcast message selectively over only one of its data link interfaces ( 3b . 3c ) to the participant ( 4 . 5 ) associated with a VLAN identified by a VLAN tag contained in the broadcast message. Communication system ( 1 ) for a packet-based communication network with a link layer and a network layer, comprising: an address administration device ( 2 ) according to any one of claims 1 to 7; and a plurality of participants ( 4 . 5 ) according to one of claims 8 or 9. Communication system ( 1 ) according to claim 13, further comprising a packet switching device ( 3 ) according to claim 10 to 12. Vehicle (F), in particular motor vehicle, with a communication system ( 1 ) according to claim 13 or 14.

Images