JP2004032004A - Switch apparatus provided with loopback port and capsulated packet switching method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a switch apparatus that eliminates processes in duplicate by connecting each protocol processing section to a loopback port via a decapsulate processing section so as to simplify and downsize its circuit system. <P>SOLUTION: A protocol processing selection section 13 selects a protocol A processing or a protocol B processing for a packet received by a reception port 15 and a loopback port 16. A decapsulate processing section 14 replaces a protocol of a capsulated packet with a protocol of an inner protocol header, eliminates an outer protocol header and transmits the resulting decapsulated packet to the loopback port 16. A protocol A processing section 11 and a protocol B processing section 12 give the packet to the decapsulate processing section 14 when the packet is a capsulated packet, and switch the packet to a transmission port 17 when the packet is not a capsulated packet. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a switch device for switching a packet, and more particularly to a switch device having a return port (also referred to as a loopback port).
[0002]
[Prior art]
Tunneling refers to encapsulating a protocol A packet as a protocol B packet by adding a protocol B protocol header to a certain protocol A packet and transferring the packet over a protocol B network. For this tunneling, when a switch device (including a router, a switching hub, etc.) that connects the protocol A network to the protocol B network receives a protocol B packet, it receives the protocol B of the outer protocol header. By examining the protocol header, it is determined whether the packet is a normal packet of the protocol B or a packet of the encapsulated protocol A. If the packet is of the encapsulated protocol A, it is the protocol B which is the outer protocol header. It is necessary to remove the protocol header (decapsulation process) and switch the protocol A packet to the protocol A network in accordance with the protocol header of the protocol A which is the inner protocol header.
[0003]
In the conventional switch device, the protocol B processing based on the outer protocol header, the decapsulation processing of the encapsulated packet, and the protocol A processing based on the inner protocol header are performed by one circuit (hardware). A protocol processing unit corresponding to all combinations of the protocol B processing based on the outer protocol header and the protocol A processing based on the inner protocol header is provided as a circuit part according to the number of protocols.
[0004]
[Problems to be solved by the invention]
In the above-described conventional switch device, since the protocol processing based on the outer protocol header, the decapsulation processing of the encapsulated packet, and the protocol processing based on the inner protocol header are performed by one circuit, the inner protocol header is used. Circuit parts to deal with all combinations of the protocol processing based on the protocol protocol and the protocol processing based on the outer protocol header are required, which causes a problem that the circuit system is increased and the processing is complicated.
[0005]
In addition, since each circuit part has the same processing part of the same protocol, there is a problem that the circuit system is wasted.
[0006]
An object of the present invention is to provide a protocol processing unit independently for each protocol and connect each protocol processing unit via a return port via a decapsulation processing unit, thereby eliminating redundant processing and simplifying and miniaturizing a circuit system. It is an object of the present invention to provide a switch device having a turn-back port that can be configured.
[0007]
Another object of the present invention is to provide an encapsulated packet switching method in a switch device having a return port.
[0008]
Prior art documents include JP-A-2000-165443, JP-A-2001-045064, JP-A-2001-285942, JP-A-2001-313672, JP-A-11-068846, and the like. It is not possible to do so, but discloses an invention having a different configuration, operation, and effect from the present invention.
[0009]
[Means for Solving the Problems]
A switch device having a return port according to the present invention includes a reception port for receiving a packet, and a transmission port for transmitting a packet, and the switch device that switches a packet received at the reception port toward the transmission port. A return port for transmitting and receiving the return, a protocol processing selecting unit for selecting a protocol processing of the packet received at the reception port and the return port, and replacing the protocol of the encapsulated packet with the protocol of the inner protocol header and the outer A decapsulation processing unit that removes the protocol header and sends the decapsulated packet to the return port; and a decapsulation packet that is provided for each protocol and that is encapsulated when the protocol processing is selected by the protocol processing selection unit. A plurality of protocol processing units for determining whether the packet is an encapsulated packet and passing the encapsulated packet to the decapsulation processing unit if the packet is an encapsulated packet, and switching the packet to the transmission port if the packet is not an encapsulated packet. And
[0010]
Further, the switch device having the return port of the present invention is a switch device that includes a reception port for receiving a packet and a transmission port for transmitting the packet, and switches the packet received at the reception port toward the transmission port. A return port for transmitting a packet and receiving the return packet; a protocol processing selecting unit for selecting a protocol process of the packet received at the reception port and the return port from a first protocol process or a second protocol process; A decapsulation processing unit that replaces a protocol with a protocol of an inner protocol header, removes an outer protocol header, and sends out a decapsulated packet to the return port; and a first protocol process is selected by the protocol process selector. A first protocol for determining whether the packet is an encapsulated packet, passing the encapsulated packet to the decapsulation processing unit if the packet is an encapsulated packet, and switching the packet to the transmission port if not an encapsulated packet A processing unit that determines whether the packet is an encapsulated packet when the second protocol processing is selected by the protocol processing selecting unit, and if the packet is an encapsulated packet, passes the encapsulated packet to the decapsulation processing unit; If it is not a packet, a second protocol processing unit that switches the packet to the transmission port is provided.
[0011]
Further, the switch device including the return port of the present invention is a switch device that includes a reception port for receiving a packet and a transmission port for transmitting the packet, and switches the packet received at the reception port toward the transmission port. A return port for transmitting and returning a packet, a protocol processing selecting unit for selecting protocol processing of the reception port and the packet received at the return port from IPv4 processing or IPv6 processing, and A decapsulation processing unit for replacing the protocol with the protocol of the protocol header, removing the outer protocol header and sending out the decapsulated packet to the return port, and a capsule when the IPv4 processing is selected by the protocol processing selection unit. An IPv4 processing unit that determines whether the packet is an encapsulated packet, passes the encapsulated packet to the decapsulation processing unit if the packet is an encapsulated packet, and switches the packet toward the transmission port if the packet is not an encapsulated packet; When the IPv6 processing is selected by the protocol processing selection unit, it is determined whether or not the packet is an encapsulated packet. If the packet is an encapsulated packet, the encapsulated packet is passed to the decapsulation processing unit. And an IPv6 processing unit that performs switching to the transmission port.
[0012]
Still further, the switch device having the return port of the present invention includes a reception port for receiving a packet, and a transmission port for transmitting the packet, wherein the switch device switches the packet received at the reception port toward the transmission port. A return port for transmitting a packet and receiving a return, a protocol processing selecting unit for selecting a protocol process according to the reception port and a type of a MAC header of the packet received at the return port, and a MAC header of the encapsulated packet. Is replaced with the protocol of the inner protocol header, the outer protocol header is removed, and the decapsulated packet is sent to the return port. A decapsulation processor is provided for each protocol, and the protocol processing selector selects the protocol. When the packet processing is selected, it is determined based on the contents of the protocol header of the packet whether or not the packet is an encapsulated packet further having a protocol header inside. If the packet is an encapsulated packet, the encapsulated packet is subjected to the decapsulation processing. And a plurality of protocol processing units for switching the packet to the transmission port if the packet is not an encapsulated packet.
[0013]
Further, the switch device having the return port of the present invention is a switch device that includes a reception port for receiving a packet and a transmission port for transmitting the packet, and switches the packet received at the reception port toward the transmission port. A return port for transmitting a packet and receiving the return, a protocol processing selection unit for selecting a first protocol process or a second protocol process according to a type of a MAC header of the packet received at the reception port and the return port; A decapsulation processor for replacing the type of the MAC header of the encapsulated packet with the protocol of the inner protocol header, removing the outer protocol header and sending the decapsulated packet to the return port, and a first processor by the protocol processing selector. When the packet processing is selected, it is determined based on the content of the first protocol header of the packet whether or not the packet is an encapsulated packet further having a protocol header inside. A first protocol processing unit that passes the packet to the transmission port if the packet is not an encapsulated packet, and a second protocol process when the second protocol process is selected by the protocol process selection unit. 2 Based on the contents of the protocol header, it is determined whether or not the packet is an encapsulated packet further having a protocol header inside. If the packet is an encapsulated packet, the encapsulated packet is passed to the decapsulation processing unit. Switch the packet to the transmission port And having a second protocol processing unit for grayed.
[0014]
Further, the switch device including the return port of the present invention is a switch device that includes a reception port for receiving a packet and a transmission port for transmitting the packet, and switches the packet received at the reception port toward the transmission port. A return port for transmitting and returning a packet, a protocol processing selection unit for selecting IPv4 processing or IPv6 processing according to the type of the reception port and the MAC header of the packet received at the return port, A decapsulation processing unit that replaces the type of the MAC header with the protocol of the inner protocol header, removes the outer protocol header, and sends out the decapsulated packet to the return port, and an IPv4 process selected by the protocol processing selection unit Then, based on the contents of the IPv4 header of the packet, it is determined whether or not the packet is an encapsulated packet further having a protocol header inside. If the packet is an encapsulated packet, the encapsulated packet is passed to the decapsulation processing unit. If the packet is not an encapsulated packet, an IPv4 processing unit that switches the packet toward the transmission port, and when the IPv6 processing is selected by the protocol processing selection unit, further based on the contents of the IPv6 header of the packet, IPv6 for judging whether or not a protocol header is an encapsulated packet, passing the encapsulated packet to the decapsulation processing unit if the packet is an encapsulated packet, and switching the packet to the transmission port if not an encapsulated packet. And a processing unit. To.
[0015]
On the other hand, in the encapsulated packet switching method of the present invention, in the encapsulated packet switching method of the switch device for switching the packet, the protocol processing unit for switching the packet according to the protocol is made independent for each protocol, Is connected to a return port via a decapsulation processing unit, so that the processing of the encapsulated packet is processed by the same protocol processing unit as the non-encapsulated packet of the same protocol.
[0016]
Also, the encapsulated packet switching method using a return port according to the present invention is the encapsulated packet switching method for a switching device that performs packet switching, wherein an IPv4 processing unit that performs packet switching according to IPv4 and an IPv4 processing unit that performs packet switching according to IPv6. The processing of an encapsulated packet is the same as that of an unencapsulated packet of the same protocol by making the IPv6 processing unit that performs packet switching independent and connecting each protocol processing unit to a return port via a decapsulation processing unit. It is characterized in that it is processed by a protocol processing unit.
[0017]
In the switch device having the loopback port of the present invention, when performing decapsulation processing of an encapsulated packet, a protocol processing unit that performs packet switching according to an outer protocol header, and a protocol that performs packet switching according to the protocol header of the decapsulated packet The processing unit is made independent of a circuit, and each protocol processing unit is connected to a return port via a decapsulation processing unit that performs decapsulation processing of an encapsulated packet, thereby realizing simplification and miniaturization of a circuit system.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0019]
Referring to FIG. 1, a switch device 10 having a return port according to a first embodiment of the present invention performs a protocol A process for switching a packet in accordance with a protocol header of protocol A (hereinafter abbreviated as protocol A header). A protocol B processing unit 12 for switching a packet in accordance with a protocol header of a protocol B (hereinafter, abbreviated as a protocol B header); a protocol processing selection unit 13 for selecting a protocol processing unit in accordance with a protocol header of a received packet; , A decapsulation processing unit 14 for performing decapsulation processing of the encapsulated packet, a reception port 15 for receiving the packet, a return port 16 for transmitting the decapsulated packet and receiving the return, and a transmission port 17 for transmitting the packet. Consists of That.
[0020]
The protocol A processing unit 11 analyzes the packet of the protocol A header received from the protocol processing selection unit 13 and performs packet switching according to the protocol A header.
[0021]
The protocol B processing unit 12 analyzes the packet of the protocol B header received from the protocol processing selection unit 13 and performs packet switching according to the protocol B header.
[0022]
The protocol processing selecting unit 13 analyzes the packet received from the receiving port 15 or the return port 16 and sends the packet to the protocol A processing unit 11 or the protocol B processing unit 12 according to the outer protocol header.
[0023]
The decapsulation processing unit 14 performs decapsulation processing of the encapsulated packets received from the protocol A processing unit 11 and the protocol B processing unit 12, and sends out the decapsulated packet to the return port 16.
[0024]
The reception port 15 is provided with one or more (one shown) according to the protocol of the network connected to the switch device 10 and receives a packet through the network.
[0025]
The return port 16 transmits the decapsulated packet from the decapsulation processing unit 14, receives the decapsulated packet, and transfers it to the protocol processing selection unit 13.
[0026]
One or more transmission ports 17 are provided according to the protocol of the network connected to the switch device 10 (one in the figure), and transmit packets to the network.
[0027]
Referring to FIG. 2, the processing procedure in the protocol A processing unit 11 and the protocol B processing unit 12 includes a packet receiving step S101, an encapsulated packet discriminating step S102, a MAC (Media Access Control) header type rewriting step S103, and a decapsulation step. The process includes a step S104 of sending a packet to the processing unit, a step S105 of rewriting a source address and a destination address, and a step S106 of switching a packet to a transmission port.
[0028]
Referring to FIG. 3, the processing procedure in the protocol processing selecting unit 13 includes a packet receiving step S201, a protocol determining step S202, and a packet sending step S203 to the relevant protocol processing unit.
[0029]
Referring to FIG. 4, the processing procedure in the decapsulation processing unit 14 includes a packet receiving step S301, an outer protocol header removing step S302, and a packet transmitting step S303 to the return port.
[0030]
Next, the operation of the switch device 10 according to the first embodiment thus configured will be described with reference to FIGS. 1 to 4 and FIGS.
[0031]
(1) Receiving normal packet of protocol A header (see FIG. 5)
[0032]
When receiving the normal packet of the protocol A header, the receiving port 15 passes the packet to the protocol processing selecting unit 13.
[0033]
Upon receiving the packet (step S201), the protocol processing selection unit 13 determines the protocol A from the type of the MAC header (step S202), and sends the packet to the protocol A processing unit 11 (step S203).
[0034]
Upon receiving the packet from the protocol processing selecting unit 13 (step S101), the protocol A processing unit 11 determines whether or not the content of the outer protocol A header is an encapsulated packet having a protocol B header inside (step S102). Since the packet does not have the protocol B header inside, the source address and the destination address of the MAC header are rewritten according to the source address and the destination address of the protocol A header (step S105), and the transmission port connected to the protocol A network is rewritten. 17 is switched (step S106).
[0035]
The transmission port 17 transmits the packet to the protocol A network.
[0036]
(2) Receiving the normal packet of the protocol B header (see FIG. 6)
[0037]
When receiving the normal packet of the protocol B header, the receiving port 15 passes the packet to the protocol processing selecting unit 13.
[0038]
Upon receiving the packet (step S201), the protocol processing selection unit 13 determines the protocol B from the type of the MAC header (step S202), and sends the packet to the protocol B processing unit 12 (step S203).
[0039]
Upon receiving the packet from the protocol processing selecting unit 13 (step S101), the protocol B processing unit 12 determines whether or not the content of the outer protocol B header is an encapsulated packet having a protocol A header inside (step S102). Since the packet has no protocol A header inside, the source address and destination address of the MAC header are rewritten according to the source address and destination address of the protocol B header (step S105), and the transmission port connected to the protocol B network 17 is switched (step S106).
[0040]
The transmission port 17 transmits the packet to the protocol B network.
[0041]
(3) Receiving the encapsulated packet of the protocol B header encapsulated by the protocol A header (see FIG. 7)
[0042]
When receiving the encapsulated packet of the protocol B header encapsulated by the protocol A header, the receiving port 15 passes the encapsulated packet to the protocol processing selecting unit 13.
[0043]
Upon receiving the encapsulated packet (step S201), the protocol processing selecting unit 13 determines the protocol A from the type of the MAC header (step S202), and sends the encapsulated packet to the protocol A processing unit 11 (step S203).
[0044]
Upon receiving the encapsulated packet from the protocol processing selecting unit 13 (step S101), the protocol A processing unit 11 determines whether or not the content of the outer protocol A header is an encapsulated packet having a protocol B header inside (step S101). (Step S102) Since the packet is an encapsulated packet, the type of the MAC header is rewritten to Protocol B of the inner protocol B header (Step S103), and the encapsulated packet is sent to the decapsulation processing unit 14 (Step S104).
[0045]
Upon receiving the encapsulated packet (step S301), the decapsulation processing unit 14 removes the protocol A header from the encapsulated packet, decapsulates the packet into a protocol B header (step S302), and returns the decapsulated packet to the return port 16. It is sent (step S303).
[0046]
The return port 16 transmits the decapsulated packet of the protocol B header received from the decapsulation processing unit 14, returns the packet, and passes it to the protocol processing selection unit 13.
[0047]
Upon receiving the decapsulated packet of the protocol B header from the return port 16 (step S201), the protocol processing selection unit 13 determines the protocol B from the type of the MAC header (step S202), and processes the decapsulated packet by the protocol B. It is sent to the unit 12 (step S203).
[0048]
Upon receiving the decapsulated packet from the protocol processing selecting unit 13 (step S101), the protocol B processing unit 12 determines whether or not the content of the outer protocol B header is an encapsulated packet having the inner protocol A header. (Step S102) Since the packet has no protocol B header inside, the source address and the destination address of the MAC header are rewritten according to the source address and the destination address of the protocol B header (step S105), and the packet is connected to the protocol B network. The packet is switched to the transmission port 17 (step S106).
[0049]
The transmission port 17 transmits the packet to the protocol B network.
[0050]
(4) Receiving an encapsulated packet of protocol A encapsulated by protocol B (see FIG. 8)
[0051]
When receiving the encapsulated packet of the protocol A header encapsulated by the protocol B header, the receiving port 15 passes the encapsulated packet to the protocol processing selecting unit 13.
[0052]
Upon receiving the encapsulated packet (step S201), the protocol processing selecting unit 13 determines the protocol B from the type of the MAC header (step S202), and sends the encapsulated packet to the protocol B processing unit 12 (step S203).
[0053]
When receiving the encapsulated packet from the protocol processing selecting unit 13 (step S101), the protocol B processing unit 12 determines whether or not the content of the outer protocol B header is an encapsulated packet having the inner protocol A header (step S101). (Step S102) Since the packet is an encapsulated packet, the type of the MAC header is rewritten to Protocol A of the inner protocol A header (Step S103), and the encapsulated packet is sent to the decapsulation processing unit 14 (Step S104).
[0054]
Upon receiving the encapsulated packet (step S301), the decapsulation processing unit 14 removes the protocol B header from the encapsulated packet, decapsulates the packet into the protocol A header (step S302), and returns the decapsulated packet to the return port 16. It is sent (step S303).
[0055]
The return port 16 transmits the decapsulated packet of the protocol A header received from the decapsulation processing unit 14, returns the packet, and passes it to the protocol processing selection unit 13.
[0056]
Upon receiving the decapsulated packet of the protocol A header from the return port 16 (step S201), the protocol processing selection unit 13 determines the protocol A from the type of the MAC header (step S202), and processes the decapsulated packet with the protocol A. It is sent to the unit 11 (step S203).
[0057]
Upon receiving the decapsulated packet from the protocol processing selecting unit 13 (step S101), the protocol A processing unit 11 determines whether or not the content of the outer protocol A header is an encapsulated packet having a protocol B header inside. (Step S102) Since the packet has no protocol B header inside, the source address and destination address of the MAC header are rewritten according to the source address and destination address of the protocol A header (step S105), and the packet is connected to the protocol A network. The packet is switched to the transmission port 17 (step S106).
[0058]
The transmission port 17 transmits the packet to the protocol A network.
[0059]
In the above embodiment, the switch device 10 is provided with the two types of protocol processing units, the protocol A processing unit 11 and the protocol B processing unit 12. If this happens, three or more protocol processing units are also provided.
[0060]
【Example】
Hereinafter, as an embodiment, a case where the protocol A is IPv4 (Internet Protocol version 4) and the protocol B is IPv6 (Internet Protocol version 6) will be described with reference to FIGS. 9 to 12.
[0061]
In IPv6, there are both a case where a tunnel is created in an IPv4 network and the IPv6 switch device 10 switches packets, and a case where a tunnel is created in an IPv6 network and the IPv4 switch device 10 switches packets. obtain. The above two types of tunnels are realized by packet encapsulation.
[0062]
FIG. 9 is a diagram illustrating an encapsulated packet when an IPv6 switch device 10 switches a packet by creating a tunnel in an IPv4 network. This encapsulated packet includes a destination MAC address (DA), a source MAC address (SA), a type, an IPv4 header, an IPv6 header, and data. The IPv4 header includes a version, a header length, a service type, a total length, an identifier (ID), a flag, a fragment offset, a time to live (TTL), a protocol type, a header checksum, and a transmission source. It consists of an IP address and a destination IP address. The destination MAC address, the source MAC address and the type are collectively referred to as a MAC header. When the type of the MAC header is 0x0800, the IPv4 header is identified, and when the protocol type of the IPv4 header is 0x29, the IPv6 header is identified.
[0063]
FIG. 10 is a diagram illustrating packets when a tunnel is created in an IPv6 network and the IPv4 switch device 10 switches packets. This packet includes a destination MAC address (DA), a source MAC address (SA), a type (IPv6 = 0x86dd), an IPv6 header, an IPv4 header, and data. The IPv6 header includes a version, a traffic class, a flow label, a payload length, a next header (IPv4 = 0x04), a hop limit, a source IP address, and a destination IP address. When the type of the MAC header is 0x86dd, the IPv6 header is identified, and when the next header of the IPv6 header is 0x04, the IPv4 header is identified.
[0064]
Note that typical values included in the protocol of the IPv4 header and the next header of the IPv6 header are 1 (0x01) in the case of ICMP (Internet Control Message Protocol), 2 (0x02) in the case of IGMP (Internet Group Management Protocol), 4 (0x04) for IP (Internet Protocol), 6 (0x06) for TCP (Transmission Control Protocol), 17 (0x11) for UDP (User Datagram Protocol), 41 (0x29) for IPv6, There are 58 (0x3a) for ICMPv6.
[0065]
FIG. 11 is a diagram illustrating an example of a decapsulation process when a tunnel is created in an IPv4 network and the IPv6 switch device 10 switches packets.
[0066]
When receiving the IPv6 packet encapsulated by IPv4 (see FIG. 11A), the receiving port 15 passes the encapsulated packet to the protocol processing selecting unit 13.
[0067]
Upon receiving the encapsulated packet (step S201), the protocol processing selecting unit 13 determines that the packet is the IPv4 based on the type of the MAC header (step S202), and sends the encapsulated packet to the IPv4 processing unit 11 (step S203).
[0068]
When receiving the encapsulated packet from the protocol processing selecting unit 13 (Step S101), the IPv4 processing unit 11 determines whether the packet is an encapsulated packet having an IPv6 header inside from the protocol of the outside IPv4 header (Step S102). Since the packet is an encapsulated packet, the type of the MAC header is rewritten to IPv6 (0x86dd) (step S103), and the encapsulated packet is sent to the decapsulation processing unit 14 (step S104).
[0069]
Upon receiving the encapsulated packet (step S301), the decapsulation processing unit 14 removes the IPv4 header from the encapsulated packet, decapsulates the packet into an IPv6 packet (step S302), and sends out the IPv6 packet to the return port 16 (step S303). .
[0070]
The return port 16 transmits the IPv6 packet, receives the return, and transfers the packet to the protocol processing selection unit 13.
[0071]
Upon receiving the packet (step S201), the protocol processing selecting unit 13 determines that the packet is IPv6 from the type of the MAC header of the packet (step S202), and sends the IPv6 packet to the IPv6 processing unit 12 (step S203).
[0072]
When receiving the packet from the protocol processing selecting unit 13 (step S101), the IPv6 processing unit 12 determines whether or not the content of the outer IPv6 header is an encapsulated packet having a protocol header inside (step S102). Since the packet has no protocol header, the source MAC address and the destination MAC address of the MAC header are rewritten according to the source IP address and the destination IP address of the IPv6 header (step S105), and the transmission port 17 connected to the IPv6 network is rewritten. The packet is switched (step S106).
[0073]
The transmission port 17 transmits a packet to an IPv6 network.
[0074]
FIG. 12 is a diagram for explaining the transition of the contents of the MAC header at each of the reception port 15, the return port 16, and the transmission port 17. In the packet (a) transmitted from the IPv4 router 20 to the switch device 10, the destination MAC address (DA) is the switch device 10, the source MAC address (SA) is the IPv4 router 20, and the type is IPv4 (= 0x0800). ing. In the packet (b) returned from the switch device 10 to the switch device 10, the destination MAC address (DA) is the switch device 10, the source MAC address (SA) is the IPv4 router 20, and the type is IPv6 (= 0x86dd). Has become. Further, in the packet (c) transmitted from the switch device 10 to the IPv6 terminal 30, the destination MAC address (DA) is the IPv6 terminal 30, the source MAC address (SA) is the switch device 10, and the type is IPv4 (= 0x086dd). It has become.
[0075]
In the embodiment, the case where the tunnel is created in the IPv4 network and the IPv6 switching device 10 switches the packet has been described. However, the tunnel is created in the IPv6 network and the IPv4 switching device 10 switches the packet. The same applies to the case, and a detailed description thereof will be omitted.
[0076]
【The invention's effect】
A first effect is that the circuit system of the switch device can be simplified and downsized. The reason is that if it is determined that decapsulation of the packet is necessary in the outer protocol header, the decapsulated packet is transmitted once and then re-received using the loopback port, and the protocol processing and encapsulation of the encapsulated packet are performed. This is because the same protocol processing unit can commonly perform the protocol processing of the unencoded packet.
[0077]
The second effect is that no waste occurs in the circuit system of the switch device. The reason is that it is not necessary for each protocol processing unit to have the same processing part of the same protocol.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration of a switch device having a return port according to a first embodiment of the present invention.
FIG. 2 is a flowchart illustrating a processing procedure of a protocol processing unit in FIG. 1;
FIG. 3 is a flowchart illustrating a processing procedure of a protocol processing selecting unit in FIG. 1;
FIG. 4 is a flowchart illustrating a processing procedure of a decapsulation processing unit in FIG. 1;
FIG. 5 is a diagram illustrating a switching flow when the switch device in FIG. 1 receives a packet of protocol A that is not encapsulated.
FIG. 6 is a diagram illustrating a switching flow when the switch device in FIG. 1 receives a packet of protocol B that is not encapsulated.
FIG. 7 is a diagram illustrating a switching flow when the switch device in FIG. 1 receives a protocol B packet encapsulated in a protocol A.
FIG. 8 is a diagram illustrating a flow of switching when the switch device in FIG. 1 receives a packet of protocol A encapsulated in protocol B.
FIG. 9 is a diagram illustrating an encapsulated packet when a tunnel is created in an IPv4 network and an IPv6 switching device switches packets.
FIG. 10 is a diagram illustrating an encapsulated packet when a tunnel is created in an IPv6 network and an IPv4 switch device switches packets.
FIG. 11 is a diagram illustrating an example of a decapsulation process when a tunnel is created in an IPv4 network and an IPv6 switching device switches packets.
FIG. 12 is a diagram for explaining transition of the contents of a MAC header at each of a reception port, a return port, and a transmission port in FIG. 1;
[Explanation of symbols]
10 Switch device
11 Protocol A processing unit
12 Protocol B processing unit
13 Protocol processing selector
14 Decapsulation processing unit
15 Receiving port
16 Return port
17 Transmission port
20 IPv4 router
30 IPv6 terminal
S101 Packet receiving step
S102 Encapsulated packet determination step
S103 MAC header type rewriting step
S104 Step of sending packet to decapsulation processing unit
S105 Rewriting source address and destination address
S106 Packet switching step to transmission port
S201 Packet receiving step
S202 Protocol determination step
S203 Step of sending packet to corresponding protocol processing unit
S301 Packet receiving step
S302 outer protocol header removal step
S303 Packet transmission step to return port

Claims (8)

A switch device that includes a reception port for receiving a packet and a transmission port for transmitting the packet, and switches the packet received at the reception port toward the transmission port.
A loopback port that sends packets and receives loopbacks,
A protocol processing selection unit that selects a protocol processing of a packet received at the reception port and the return port,
A decapsulation processing unit that replaces the protocol of the encapsulated packet with the protocol of the inner protocol header, removes the outer protocol header, and sends out the decapsulated packet to the return port;
It is provided for each protocol, and when the protocol processing is selected by the protocol processing selecting unit, it is determined whether or not the packet is an encapsulated packet. If the packet is an encapsulated packet, the encapsulated packet is passed to the decapsulation processing unit. A switch device having a return port, comprising: a plurality of protocol processing units that switch the packet to the transmission port if the packet is not a packet. A switch device that includes a reception port for receiving a packet and a transmission port for transmitting the packet, and switches the packet received at the reception port toward the transmission port.
A loopback port that sends packets and receives loopbacks,
A protocol processing selecting unit that selects a protocol processing of a packet received at the receiving port and the return port from a first protocol processing or a second protocol processing;
A decapsulation processing unit that replaces the protocol of the encapsulated packet with the protocol of the inner protocol header, removes the outer protocol header, and sends out the decapsulated packet to the return port;
When the first protocol process is selected by the protocol process selecting unit, it is determined whether or not the packet is an encapsulated packet. If the packet is an encapsulated packet, the encapsulated packet is passed to the decapsulating unit. A first protocol processing unit for switching the packet toward the transmission port;
When the second protocol processing is selected by the protocol processing selection unit, it is determined whether the packet is an encapsulated packet. If the packet is an encapsulated packet, the encapsulated packet is passed to the decapsulation processing unit. And a second protocol processing unit for switching the packet toward the transmission port. A switch device that includes a reception port for receiving a packet and a transmission port for transmitting the packet, and switches the packet received at the reception port toward the transmission port.
A loopback port that sends packets and receives loopbacks,
A protocol processing selecting unit for selecting protocol processing of a packet received at the receiving port and the return port from IPv4 processing or IPv6 processing;
A decapsulation processing unit that replaces the protocol of the encapsulated packet with the protocol of the inner protocol header, removes the outer protocol header, and sends out the decapsulated packet to the return port;
When IPv4 processing is selected by the protocol processing selection unit, it is determined whether the packet is an encapsulated packet. If the packet is an encapsulated packet, the encapsulated packet is passed to the decapsulation processing unit. An IPv4 processing unit for switching a packet toward the transmission port;
When IPv6 processing is selected by the protocol processing selection unit, it is determined whether or not the packet is an encapsulated packet. If the packet is an encapsulated packet, the encapsulated packet is passed to the decapsulation processing unit. A switch device having a return port, comprising: an IPv6 processing unit that switches a packet toward the transmission port. A switch device that includes a reception port for receiving a packet and a transmission port for transmitting the packet, and switches the packet received at the reception port toward the transmission port.
A loopback port that sends packets and receives loopbacks,
A protocol processing selection unit that selects a protocol processing according to a type of a MAC header of a packet received at the reception port and the return port;
A decapsulation processing unit that replaces the type of the MAC header of the encapsulated packet with the protocol of the inner protocol header, removes the outer protocol header, and sends out the decapsulated packet to the return port;
Provided for each protocol, when the protocol processing is selected by the protocol processing selection unit, based on the contents of the protocol header of the packet, determine whether or not the encapsulated packet further includes a protocol header inside, And a plurality of protocol processing units for switching the packet to the transmission port if the packet is an encapsulated packet and passing the encapsulated packet to the decapsulation processing unit if the packet is not an encapsulated packet. Switch device. A switch device that includes a reception port for receiving a packet and a transmission port for transmitting the packet, and switches the packet received at the reception port toward the transmission port.
A loopback port that sends packets and receives loopbacks,
A protocol processing selecting unit that selects a first protocol processing or a second protocol processing according to a type of a MAC header of a packet received at the reception port and the return port;
A decapsulation processing unit that replaces the type of the MAC header of the encapsulated packet with the protocol of the inner protocol header, removes the outer protocol header, and sends out the decapsulated packet to the return port;
When the first protocol processing is selected by the protocol processing selecting unit, it is determined whether or not the packet is an encapsulated packet further having a protocol header inside based on the content of the first protocol header of the packet. If so, a first protocol processing unit that passes the encapsulated packet to the decapsulation processing unit, and if not, switches the packet toward the transmission port;
When the second protocol processing is selected by the protocol processing selection unit, it is determined whether or not the packet is an encapsulated packet further having a protocol header inside based on the content of the second protocol header of the packet. And a second protocol processing unit that switches the packet to the transmission port if the encapsulated packet is passed to the decapsulation processing unit if the packet is not an encapsulated packet. . A switch device that includes a reception port for receiving a packet and a transmission port for transmitting the packet, and switches the packet received at the reception port toward the transmission port.
A loopback port that sends packets and receives loopbacks,
A protocol processing selection unit that selects IPv4 processing or IPv6 processing according to a type of a MAC header of a packet received at the reception port and the return port;
A decapsulation processing unit that replaces the type of the MAC header of the encapsulated packet with the protocol of the inner protocol header, removes the outer protocol header, and sends out the decapsulated packet to the return port;
When IPv4 processing is selected by the protocol processing selecting unit, it is determined whether or not the packet is an encapsulated packet having a protocol header further inside based on the contents of the IPv4 header of the packet. An IPv4 processing unit that passes an encapsulated packet to the decapsulation processing unit, and switches the packet to the transmission port if the packet is not an encapsulated packet;
When the IPv6 processing is selected by the protocol processing selecting unit, it is determined whether or not the packet is an encapsulated packet having a protocol header further inside based on the contents of the IPv6 header of the packet. A switching unit that passes the encapsulated packet to the decapsulation unit and switches the packet to the transmission port if the packet is not an encapsulated packet. In an encapsulated packet switching method of a switch device that performs packet switching,
Encapsulation of encapsulated packets in the same protocol by making the protocol processing unit that performs packet switching according to the protocol independent for each protocol, and connecting each protocol processing unit to the return port via the decapsulation processing unit An encapsulated packet switching method using a loopback port, wherein a packet that has not been processed is processed by the same protocol processing unit. In an encapsulated packet switching method of a switch device that performs packet switching,
By making the IPv4 processing unit that switches packets according to IPv4 and the IPv6 processing unit that switches packets according to IPv6 independent, and connecting each protocol processing unit to a return port via a decapsulation processing unit, An encapsulated packet switching method using a loopback port, wherein processing of an encapsulated packet is processed by the same protocol processing unit as a non-encapsulated packet of the same protocol.

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