METHOD FOR ACCESSING INTERNET VIA A VEHICLE NETWORK

• US 20150109962A1
• Filed: 10/23/2014
• Published: 04/23/2015
• Est. Priority Date: 10/23/2013
• Status: Active Grant

• Current Assignee: University Of Electronic Sceince And Technology Of China, University of Electronic Science and Technology of China
• Original Assignee: University of Electronic Science and Technology of China
• Inventors: XU, Du, LIAO, Dan, SUN, Gang, YU, Hongfang, QIU, Bing, ZHAO, Peng
• Granted Patent: US 9,391,891 B2
• Time in Patent Office: Days
• US Class Current: 370/254
• CPC Class Codes: H04L 12/6418 Hybrid transport
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04L 45/741 Routing in networks with a plurality of addressing schemes, e.g. with both IPv4 and IPv6
• CPC Class Codes: H04L 61/2514 between local and global IP addresses
• CPC Class Codes: H04L 61/5014 using dynamic host configuration protocol [DHCP] or bootstrap protocol [BOOTP]

Abstract

The present invention provides a method for accessing internet via a vehicle network. Vehicle terminal equipment can access OBU by means of the wireless AP on OBU, and realize the mutual communication with internet with the help of VANET network composed by OBU and RSU. Not only the normal communication between the OBU and RSU is guaranteed, but also the communication between vehicle terminal equipment and internet can be realized. Moreover, the present invention has the characteristics of anti-interference, convenience and real-time performance, and can adapt to the demand of the current network.

Claims

1. A method for accessing internet via a vehicle network, comprising the following steps:

(1). assigning a IPv4 address to a vehicle terminal equipment through the DHCP(Dynamic Host Configuration Protocol), wherein;

OBU (On-Board Unit) is configured as a DHCP server, and a static IPv4 address, a subnet mask and a default gateway are set up for it;

when a vehicle terminal equipment apply to the DHCP server for a IPv4 address, DHCP server selects an IPv4 address which has not been used, from a set of IPv4 addresses for dynamic allocating;

thus, different IPv4 address is assigned to different vehicle terminal equipment on OBU;

(2). sending a packet from the vehicle terminal equipment to internet;

2.1). a vehicle terminal equipment sends a IPv4 packet to OBU, OBU receives and processes the IPv4 packet, wherein;

after receiving an IPv4 packet, OBU will inquire the destination address of the IPv4 packet to determine how to process the IPv4 packet, if the destination address is an external internet address, the IPv4 packet will be sent to and processed by Roadside Unit (RSU), if the destination address is an internal IPv4 address, i.e. an address of OBU, the IPv4 packet will be processed by the upper layer protocol of OBU, otherwise, the IPv4 packet will be discarded;

2.2). wherein, the destination address of the IPv4 packet is an external internet address, the IPv4 packet will be processed by tunnel technology in the IPv4 private network part of OBU;

the IPv4 packet is sent to the private network part of OBU, then its corresponding layer header will be deleted, the remainder of the IPv4 packet is the IPv4 layer packet, and taken as an original IPv4 packet;

the original IPv4 packet will be sent to Vehicle Ad-hoc Network(VANET) private network part of OBU and encapsulated into UDP data portion in UDP layer of VANET private network part of OBU, and then, UDP header is added to the UPD data portion, thus a UDP packet is obtained;

the UDP packet is sent to the IPv6 layer;

the UDP packet will be submitted from higher layer to lower layer with encapsulating corresponding layer header in VANET private network part of OBU, and in the end, the UDP packet is sent out by the wireless network card which is working at Ad-hoc mode;

2.3). wherein, after receiving the UDP packet from OBU, RSU will process the UDP packet with tunnel technology in the private network part of RSU;

the UDP packet will be submitted from lower layer to higher layer with deleting the corresponding layer header, in the end, the UDP packet is submitted to the UDP layer, and is processed according to the UDP data portion, if the UDP data portion is the original IPv4 packet, the UDP packet will be processed in the IPv4 private network part of RSU to take the original IPv4 packet out, otherwise submitted to application layer for further process;

wherein, the original IPv4 packet will be added with MAC header to obtain an sending packet, the sending packet is submitted to the MAC layer;

the sending packet is sent to internet by Ethernet or other means after the Network Address Translation (NAT) transformation;

NAT translates the private IPv4 address of sending packet into legitimate public IPv4 address, then sends the sending packet to internet, and records the transmission path information simultaneously;

(3). returning a packet from internet to the vehicle terminal equipment;

3.1). after receiving a packet from the vehicle terminal equipment, internet returns a packet, i.e. return packet to the vehicle terminal equipment;

wherein the return packet from internet is transformed through NAT, NAT will find out the vehicle terminal equipment of the return packet via the transmission path information previously recorded, and translates the public IPv4 address of the return packet into the private IPv4 address;

3.2). RSU processes the return packet;

wherein after receiving the return packet, RSU will process the return packet through inquiring the private IPv4 address of the return packet, if the private IPv4 address, i.e. destination address is a local IPv4 address of RSU, the return packet will be submitted to the transport layer to process, if the private IPv4 address is the private IPv4 address of OBU, then the return packet will be submitted to the private network part of RSU and sent to the OBU;

otherwise, the return packet will be discarded;

3.3), wherein, when the private IPv4 address of the return packet is of OBU, the return packet will enter into the IPv4 private network part of RSU, and be processed with tunnel technology;

the corresponding layer header of the return packet is deleted, the remainder of return packet is IPv4 layer packet, and taken as an original return IPv4 packet;

the original return IPv4 packet will be encapsulated into UDP data portion in UDP layer of VANET private network part of RSU, and then, a UDP header is added to the UPD data portion, thus a UDP packet is obtained;

the UDP packet is sent to the IPv6 layer, the UDP packet will be submitted from higher layer to lower layer with encapsulating corresponding layer header in VANET private network part of RSU, and in the end, the UDP packet is sent out by the wireless network card which is working at Ad-hoc mode;

3.4). wherein, after receiving the UDP packet from RSU, OBU will process the UDP packet with tunnel technology in the private network part of OBU;

the UDP packet will be submitted from lower layer to higher layer with deleting the corresponding layer header in VANET private network part of OBU, in the end, the UDP packet is submitted to the UDP layer of VANET private network part of OBU, and is processed according to the UDP data portion, if the UDP data portion is the packet returning from internet to vehicle terminal equipment, the UDP packet will be processed in the IPv4 private network part of OBU to take the original return IPv4 packet out, otherwise submitted to application layer for further process;

wherein, the original return IPv4 packet will be added with MAC header to obtain a final return packet, the final return packet is submitted to the MAC layer, and sent to the vehicle terminal equipment by the wireless card of OBU which is working at AP mode.

2. A method for method for accessing internet via a vehicle network of claim 1, wherein, the said tunnel technology is that:

the data transmitted by tunnel can be a different protocol data frame or data packet, the tunnel protocol repackages the other protocol data frame or data packet, and send it out through tunnel, the encapsulated frame head contains routing information.

3. A method for method for accessing internet via a vehicle network of claim 1, wherein, the said NAT adopts the port multiplexing method to realize that all hosts in IPv4 private network can share a legitimate external IPv4 address.

4. A method for method for accessing internet via a vehicle network of claim 1, wherein, in step 2.2), the said IPv4 packet is a MAC packet, and its corresponding layer header is MAC layer header;

the said encapsulating corresponding layer header is that the UDP packet is encapsulated with IPv6 header, thus a IPv6 packet is obtained, and sent to IPv6 layer;

The IPv6 packet is encapsulated with MAC header, thus a MAC packet is obtained, and sent to MAC layer.

5. A method for method for accessing internet via a vehicle network of claim 1, wherein, in VANET private network, the UPD packet is added a Forward Control Character (FCC), which comprises of Forward Flags (FF) and Forward Hop Limit (FHL), wherein, FF is used to identify whether the UPD packet need Multi-Hop forward, FHL refers to the total number of UPD packet can be forwarded in VANET, when the UPD packet is forwarded, it will minus 1;

the UPD packet will be forwarded in VANET, until its FHL is zero;

when a vehicle in VANET private network receive a the UPD packet, it will check the FCC, if the FF is “

forwarded forcibly”

, and FHL is not zero, the UPD packet will be forwarded.