KR101231744B1 - Packet transport layer apparatus - Google Patents

Abstract

The present invention relates to a packet forwarding layer device, and more particularly, by dividing a single physical port into a plurality of virtual ports according to a frame format, it is possible to accommodate frames of different formats through the same port. The number of C-VLANs and S-VLANs available at the same time is increased by assigning different component IDs and adding component IDs as a factor for searching the filtering table, and converting the frame format to match the frame format assigned to the virtual output port. A packet forwarding layer device comprising a function is provided.

Packet forwarding layer, C-VLAN, S-VLAN, B-VLAN, frame format conversion

Description

Packet forwarding layer device {PACKET TRANSPORT LAYER APPARATUS}

The present invention relates to a packet forwarding layer device, and more particularly, by dividing a single physical port into a plurality of virtual ports according to a frame format, it is possible to accommodate frames of different formats through the same port. The number of C-VLANs and S-VLANs available at the same time is increased by assigning different component IDs and adding component IDs as a factor for searching the filtering table, and converting the frame format to match the frame format assigned to the virtual output port. A packet forwarding layer device comprising a function is provided.

The present invention is derived from the research conducted as part of the IT growth engine technology development project of the Ministry of Knowledge Economy and the Ministry of Information and Telecommunication Research and Development. [Task management number: 2008-S-009-02, Task name: Packet-optical integrated switch technology development] ].

Packet transport layers such as T-MPLS or PBB-TE are packet-based transport layers that accept various Ethernet frames. Specifically, in the Ethernet network, packets are delivered in the form of untagged frames, which are basic Ethernet frames, and C-tag frames tagged with VLAN tags of 802.1Q. In provider bridge networks, packets are delivered in S-tag frames of 802.1ad. The packet is delivered in the form of a backbone core network, and the packet is delivered in the form of a B-tag frame of 802.1ah. The edge of the packet forwarding layer accepts the above Ethernet and provider bridge networks and connects them to the backbone core network. Accordingly, the ingress of the packet forwarding layer requires a function of converting Ethernet frames (that is, untag frames and C-tag frames) and S-tag frames into B-tag frames, and the output section (Egress) It requires the function of converting B-tag frames to Ethernet frames or S-tag frames.

In the conventional packet transport layer, different physical ports are allocated for each frame format. In other words, the conventional packet transport layer has a problem that one physical port can accommodate only one frame format, and the Ethernet network and the provider bridge network cannot be connected to the same physical port.

On the other hand, since the VLAN ID is composed of 12 bits, in principle, it can have 4096 VLAN IDs. However, when the Ethernet network and the provider bridge network are simultaneously accommodated and the C-VID (Customer VLAN ID) and the S-VID (Service VLAN ID) are used together, the sum of the C-VID and the S-VID is 4096. There is a problem in that 4096 C-VIDs and S-VIDs cannot be provided.

Accordingly, the present invention is to solve the problems of the prior art as described above, by dividing one physical port into a plurality of virtual ports according to the frame format can accommodate the frame of different formats through the same port, the frame The number of C-VLANs and S-VLANs available at the same time is increased by assigning different component IDs according to the format and adding the component ID as a parameter for searching the filtering table, and adjusting the frame format to match the frame format assigned to the virtual output port. It is to provide a packet forwarding layer device including a function for converting.

In order to achieve the above object, the packet forwarding layer apparatus according to the present invention receives a frame having a different format through one CNP (Customer Network Port) port, and assigns a component ID according to the received frame format. An I-component input unit encapsulating the received frame into an I-tag and outputting the same through a virtual output port; A B-component input unit encapsulating an I-tag frame received from the I-component input unit through a virtual input port into a B-tag and outputting the same through a PNP (Provider Network Port) port; A B-component output unit which removes the B-tag from the B-tag frame received through the PNP port, converts the B-tag into an I-tag frame, and outputs the same through the virtual output port; And removing the I-tag from the I-tag frame received from the B-component output unit through the virtual input port and assigning a component ID according to the format of the frame, and assigning a component ID according to the component ID and the T-component ID value. It includes an I-component output that converts the format and outputs it through the CNP port.

Here, the I-component input unit classifies the frames received through the CNP port according to the frame format, thereby recognizing the C-VLAN aware I-component searcher, the unrecognized I-component searcher, and the S-VLAN aware I-component search. A frame classification unit for transmitting to any one of the units; Receives a C-tag frame from the frame classifier and gives a C-VLAN aware I-component as a component ID, receives a C-tag frame tagged with a default VLAN ID from the unrecognized I-component searcher, and filters it. A C-VLAN aware I-component searcher for searching the table to obtain virtual output port information; An unrecognized I-component retrieval unit which receives an untagged frame from the frame classifier and assigns an unrecognized I-component to a component ID and allocates a default VLAN ID to a C-VID; An S-VLAN aware I-component searcher which receives an S-tag frame from the frame classifier and assigns an S-VLAN aware I-component as a component ID, and searches the filtering table to obtain virtual output port information; And an I-tag encapsulation unit generating an I-tag and tagging the I-tag in a frame received from the C-VLAN aware I-component searcher or the S-VLAN aware I-component searcher.

The B-component input unit may include: a B-component search unit that retrieves a filtering table to obtain virtual output port information for the I-tag frame; A B-tag encapsulation unit generating a B-tag, tagging the B-tag on an I-tag frame received from the B-component searcher, and outputting the B-tag through a virtual output port; And frame tag switching / integration, which retrieves a B-tag frame received from the B-tag encapsulation unit through the physical output port after obtaining a physical output port information corresponding to the virtual output port by searching a port table. Contains wealth.

The B-component output unit may include: a B-component search unit that retrieves a filtering table to obtain virtual output port information for the B-tag frame; And a B-tag removal unit which removes the B-tag from the B-tag frame received from the B-component searcher and outputs the same through the virtual output port.

The I-component output unit may further include an I-tag removal unit for removing the I-tag from the received I-tag frame; A frame classifying unit classifying the frame received from the I-tag removing unit according to a frame format and transmitting the classified frame to a C-VLAN aware I-component searcher or an S-VLAN aware I-component searcher; A C-VLAN aware I-component searcher which receives the C-tag frame from the frame classifier, gives a C-VLAN aware I-component as a component ID, and searches the filtering table to obtain virtual output port information; An S-VLAN aware I-component searcher which receives an S-tag frame from the frame classifier and assigns an S-VLAN aware I-component as a component ID, and searches the filtering table to obtain virtual output port information; And receiving the C-tag frame or the S-tag frame from the C-VLAN aware I-component searcher or the S-VLAN aware I-component searcher, searching the port table for T-component ID and physical output port information. And a frame tag switching / integrating unit for converting and outputting the format of the frame according to the component ID and the T-component ID value.

Specifically, the frame tag switching / integrating unit outputs without converting the frame format when the T-component ID is 0, and when the component ID is an S-VLAN aware I-component, the T-component ID is C. If the VLAN-aware I-component is converted into a C-tag frame and outputted, if the T-component ID is not a C-VLAN-aware I-component, it is converted into an untagged frame and the component ID is a C-VLAN-aware I. In the case of a component, if the T-component ID is an S-VLAN aware I-component, the T-component ID is converted into an S-tag frame, and if the T-component ID is not an S-VLAN aware I-component, the T-component ID is converted into an untag frame. Output

The filtering table includes a component ID field, and has a physical output port or virtual output port information in a port number field, and includes a component ID as a search factor for searching the filtering table.

In addition, the port table stores a mapping relationship between the virtual output porter and the physical output port and includes a T-component ID field indicating whether to convert the frame format.

According to the present invention, it is possible to simultaneously receive frames of different formats through one physical port and transfer them to the backbone core network, and convert the frames transmitted from the backbone core network into an appropriate frame format according to the type of the network connected to the edge. can do. Accordingly, flexibility required for network design and configuration can be improved.

In addition, by assigning a component ID according to the frame format and adding it as a factor for searching the filtering table, up to 4096 12-bit VLAN IDs, that is, C-VID and S-VID, can be used. Accordingly, the number of C-VLANs and S-VLANs that can be used simultaneously is increased, thereby improving network scalability.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. In the following detailed description of the preferred embodiments of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. In the drawings, like reference numerals are used throughout the drawings.

In addition, in the entire specification, when a part is referred to as being 'connected' to another part, it may be referred to as 'indirectly connected' not only with 'directly connected' . Also, to "include" an element means that it may include other elements, rather than excluding other elements, unless specifically stated otherwise.

1 is a structural diagram of a conventional packet transport layer (PTL) to which the PBB-TE technology is applied.

As shown in FIG. 1, packet forwarding layer 100 is comprised of I-components 110 and 140 and B-components 120 and 130.

I-Component provides I-SID (Backbone Service Instance Identifier) to C-tag frame, Un-tag frame and S-tag frame which are input through CNP (Customer Network Port) port connected to Ethernet network and provider bridge network. After generating an I-tag frame, the I-component input unit 110 outputs the B-component input unit 120 through a PIP port (PIP), and the I-component input from the B-component output unit 130. It includes an I-component output unit 140 that removes an I-tag from a tag frame and converts it into a C-tag frame, an untag frame, or an S-tag frame, and then outputs it to an Ethernet network or a provider bridge network through a CNP port. do.

In addition, the B-component generates a B-tag frame by assigning a B-VID (B-VLAN ID) to an I-tag frame input from the I-component input unit 110 through a CBP (Customer Backbone Port) port. After the B-component input unit 120 outputs to the backbone core network through the PNP port and the B-tag frame input through the PNP port connected to the backbone core network, the I-tag is removed. It converts to a frame and includes a B-component output unit 130 for outputting to the I-component output unit 140 through the CBP port.

Meanwhile, the filtering table 200, the service instance table 300, and the service instance ID table 400 used by the I-components 110 and 140 and the B-components 120 and 130 in the packet forwarding layer 100. The structures of are as shown in Tables 1 to 3, respectively.

Field name Explanation DA I-Component Input / Output C-DA B-Component Input / Output B-DA VLAN ID I-Component Input / Output (C-Tag Frame) C-VID I-Component Input / Output (S-Tag Frame) S-VID B-Component Input / Output (B-Tag Frame) B-VID Port number Output port number B-DA Backbone Destination MAC Address I-SID Local I-SID B-VID Replace B-VID Flow ID Flow number direction I-Component Input / I-Component Output
B-Component Input / B-Component Output Valid 1 (valid) / 0 (free)

Field name Explanation I-SID B-Component Input Local I-SID B-Component Output Backbone I-SID B-VID Backbone VLAN ID TI-SID B-Component Input Backbone I-SID B-Component Output Local I-SID Flow ID Flow number direction B-Component Input / B-Component Output Valid 1 (valid) / 0 (free)

Field name Explanation C-DA C-DA VLAN ID C-tag frame C-VID S-tag frame S-VID I-SID Local I-SID Valid 1 (valid) / 0 (free)

First, prior to describing the packet forwarding layer apparatus and the packet processing method according to the present invention, a description will be given of a tag type for distinguishing an Ethernet type and a frame format for each tag type.

Table 4 shows tag types and values for classifying Ethernet types defined in the IEEE 802.1 standard.

Tag Type Explanation value C-VLAN tag 802.1Q tag protocol type (802.1Q tag type) 8100 S-VLAN Tag / B-VLAN Tag 802.1Q Service Tag Type (802.1QS Tag Type) 88a8 Backbone Service Instance Tag 802.1Q Backbone Service Instance Tag Type (802.1QI Tag Type) 88e7

The frame format is divided into Ethernet types shown in Table 4. In other words, the C-tag frame has 8100 (hex) as the Tag Protocol ID (TPID) value, the S-tag frame and the B-tag frame have 88a8 (hex) as the TPID value, and the I-tag frame has the TPID value. Has 88e7 (hex). On the other hand, an untagged untagged frame has 0800 (hex) as the TPID value.

The frame format for each tag type as described above is illustrated in FIGS. 2A to 2D.

2A shows the C-tag frame format. The C-tag consists of a Tag Protocol ID (TPID) having a value of 8100 (hex), a C-PCP indicating priority, a Canonical Format Identifier (CFI) indicating standard format, and a C-VLAN ID (C-VID). .

2B shows the S-tag frame format. The S-tag is located between the Customer Source MAC Address (C-SA) and the C-tag, and has a TPID of 88a8 (hex), an S-PCP indicating priority, an S-DEI and an S-VID indicating whether to discard. (S-VLAN ID).

2C shows the I-tag frame format. The I-tag is located between the B-SA (Backbone Source MAC Address) and the S-tag. The I-tag is a TPID with a value of 88e7 (hex), an I-PCP indicating priority, an I-DEI indicating discarding, or a customer address. It consists of Use Customer Address (UCA), Backbone Service Instance Identifier (I-SID), Customer Destination MAC Address (C-DA), and Customer Source MAC Address (C-SA).

2D shows the B-tag frame format. The B-tag is located between the B-SA and the I-tag, and has a TPID having a value of 88a8 (hex), a B-PCP indicating priority, a B-DEI indicating whether to discard, and a B-VID (B-VLAN ID It is composed of

Meanwhile, the untag frame means a pure Ethernet frame having no C-tag.

3 is a structural diagram of a packet forwarding layer according to an embodiment of the present invention.

Referring to FIG. 3, the packet transfer layer 100 receives frames of different formats through one CNP port, assigns component IDs according to the format of the received frames, and then I-tags the received frames. Encapsulates an I-component input unit 110 to be output through a virtual output port, and an I-tag frame received from the I-component input unit 110 through a virtual input port by encapsulating a B-tag into a PNP (Provider Network). Port) The B-component input unit 120 outputs through the port and the B-tag frame removed from the B-tag frame received through the PNP port, converted into an I-tag frame, and then output through the virtual output port. After removing the I-tag from the I-tag frame received from the B-component output unit 130 through the component output unit 130 and the virtual input port, the component ID is assigned according to the format of the frame, and the component ID is provided.Converting a format of a frame according to the T- component ID value comprises the I- component output section 140 for outputting via the port CNP.

4A to 4D are detailed structural diagrams of a packet forwarding layer according to an embodiment of the present invention. FIG. 4A is a detailed structure of an I-component input unit, FIG. 4B is a detailed structure of a B-component input unit, and FIG. 4C is B. -Detailed structure of the component output section, and FIG. 4D shows the detailed structure of the I-component output section.

Referring to FIG. 4A, the I-component input unit 110 includes a frame classifier 112, a C-VLAN recognition I-component search unit 113, an unrecognized I-component search unit 114, and an S-VLAN recognition I. A component searching unit 115 and an I-tag encapsulation unit 116.

The frame classifier 112 classifies the frames of different formats input through one CNP port 111, and according to the frame format, the C-VLAN recognition I-component search unit 113 and the unrecognized I-component search unit And the S-VLAN aware I-component searcher 115. Specifically, the frame classifier 112 extracts the TPID value, VLAN ID, and C-DA of the tag from the input frame, classifies the frame according to the format using the TPID value, and the C-tag frame is a C-VLAN. The recognition I-component retrieval unit 113 transmits the S-tag frame to the S-VLAN recognition I-component retrieval unit 115, and the untag frame to the unrecognized I-component retrieval unit 114, respectively.

The C-VLAN aware I-component searcher 113 receives the C-tag frame from the frame classifier 112 and assigns the C-VLAN aware I-component to the component ID. In addition, the C-VLAN aware I-component searcher 113 receives a C-tag frame to which a default C-VID and a component ID have been assigned to the untagged frame from the unrecognized I-component searcher 114. Thereafter, the C-VLAN aware I-component search unit 113 searches the filtering table 200 using the C-DA, C-VID, and component ID to convert the C-tag frame into an I-tag frame. Obtain the necessary B-DA, B-SA, local I-SID and virtual output port information.

The unrecognized I-component search unit 114 receives the untagged frame from the frame classifier 112, assigns the unrecognized I-component to the component ID, allocates the default VLAN ID to the C-VID, and then assigns the C-VID to the C-VID. It forwards to the VLAN aware I-component search unit 113.

The S-VLAN aware I-component searcher 115 receives the S-tag frame from the frame classifier 112 and assigns the S-VLAN aware I-component to the component ID. Subsequently, the S-VLAN aware I-component search unit 115 searches the filtering table 200 by using the C-DA, S-VID, and component ID to convert the S-tag frame into an I-tag frame. Obtain the necessary B-DA, B-SA, local I-SID and virtual output port information.

As such, by adding a component ID according to a tag type as a parameter for retrieving information required to generate an I-tag frame, the C-VID and the S-VID are mapped to different entries in the filtering table 200 even if they are the same value. Therefore, up to 4096 C-VIDs and S-VIDs can be used. To this end, the configuration of the filtering table 200 should be modified. A detailed description of the filtering table 200 will be described later.

The I-tag encapsulation unit 116 receives a C-tag frame or an S-tag frame from the C-VLAN aware I-component searcher 113 and the S-VLAN aware I-component searcher 115, and filters the table. After generating the I-tag using the information obtained by searching for the 200, the generated I-tag is tagged (that is, encapsulated) in the received frame and output through the virtual output ports 117 and 118. . As such, the use of the virtual output port concept for output ports allows the simultaneous reception of frames of different formats over the same physical port.

Referring to FIG. 4B, the B-component input unit 120 includes a B-component search unit 123, a B-tag encapsulation unit 124, and a frame tag switching / integrating unit 126.

The B-component search unit 123 extracts the local I-SID and the B-DA from the I-tag frames received through the virtual ports 121 and 122. Thereafter, the B-component search unit 123 searches the service instance table 300 using the local I-SID to obtain a backbone I-SID and a B-VID. In addition, the B-component search unit 123 searches the filtering table 200 using the B-DA and the B-VID to obtain virtual output port information. In this case, the service instance table 300 may be used without modification the service instance table used in the conventional packet delivery layer shown in Table 2.

The B-tag encapsulation unit 124 replaces the local I-SID of the I-tag frame received from the virtual port with the backbone I-SID obtained from the B-component retrieval unit 123, and then generates a B-tag. . Thereafter, the B-tag encapsulation unit 124 tags the generated B-tag on the received I-tag frame and outputs the same through the virtual output port 125.

The frame tag switch / integrator 126 searches the port table 500 using the virtual output port information to obtain physical output port (PNP) information. Thereafter, the frame tag switch / integrator 126 outputs the B-tag frame received from the B-tag encapsulator 124 to the backbone core network through the physical output port 127. In this case, the port table 500 is a table newly introduced in the present invention, and a detailed description of the port table 500 will be described later.

Referring to FIG. 4C, the B-component output unit 130 includes a B-component search unit 132 and a B-tag removal unit 133.

The B-component search unit 132 receives the B-tag frame from the backbone core network through the PNP port 131 and extracts the backbone I-SID, B-DA, and B-VID from the received B-tag frame. . Subsequently, the B-component search unit 132 searches the filtering table 200 using the B-DA and the B-VID to obtain virtual output port (VIP) information, and uses the backbone I-SID to provide the service instance table. Search 300 to obtain a local I-SID.

The B-tag removal unit 133 replaces the backbone I-SID of the B-tag frame received from the PNP port with a local I-SID obtained from the B-component search unit 132, and in the received B-tag frame. After the B-tag is removed and converted into an I-tag frame, the I-tag frame is output through the virtual output port 134.

Referring to FIG. 4D, the I-component output unit 140 includes an I-tag removing unit 142, a frame classifying unit 143, a C-VLAN recognition I-component search unit 144, and an S-VLAN recognition I-. And a component searching unit 146 and a frame tag switching / integrating unit 148.

The I-tag remover 142 removes the I-tag from the I-tag frame input through the VIP port 141 and transfers the I-tag to the frame classifier 143.

The frame classifier 143 extracts the TPID value, the VLAN ID, and the C-DA of the tag from the received frame, classifies the frame according to the format using the TPID value, and the C-tag frame recognizes the C-VLAN. The component retrieval unit 144 and the S-tag frame are forwarded to the S-VLAN aware I-component retrieval unit 146, respectively.

The C-VLAN aware I-component searcher 144 receives the C-tag frame from the frame classifier 143 and assigns the C-VLAN aware I-component to the component ID. Thereafter, the C-VLAN aware I-component searcher 144 retrieves the virtual output port information by searching the filtering table 200 using the C-DA, the C-VID, and the component ID.

The S-VLAN aware I-component searcher 146 receives the S-tag frame from the frame classifier 143 and assigns the S-VLAN aware I-component to the component ID. Thereafter, the S-VLAN aware I-component searcher 146 searches the filtering table 200 by using the C-DA, S-VID, and component ID to obtain virtual output port information.

The frame tag switching / integrating unit 148 is a C-tag frame or S- from the C-VLAN aware I-component searcher 144 and the S-VLAN aware I-component searcher 146 via the virtual port 147. Receive a tag frame. Thereafter, the frame tag switching / integrating unit 148 searches the port table 500 using the virtual output port information to obtain default VLAN ID, component ID, T-component ID, and corresponding output port (CNP) information. .

The frame tag switching / integrating unit 148 appropriately converts the format of the received frame according to the component ID and the T-component ID value and outputs it through the output port 149. Detailed description of the frame format conversion is shown in FIG. 6E. It will be described later with reference to.

Meanwhile, the tables used in the packet forwarding layer apparatus according to the present invention include a filtering table 200, a service instance table 300, and a port table 500.

Among these, the service instance table 300 uses the service instance table used in the conventional packet delivery layer shown in Table 2 as it is, without modification.

In addition, the filtering table 200 has a configuration in which the conventional filtering table is partially modified as shown in Table 5. In detail, the filtering table 200 used in the present invention differs from the conventional filtering table in that a virtual output port information as well as a physical output port is put in a port number field, and a field called a component ID is newly added. There is.

Field name Explanation DA I-Component Input / Output C-DA B-Component Input / Output B-DA VLAN ID I-Component Input / Output (C-Tag Frame) C-VID I-Component Input / Output (S-Tag Frame) S-VID B-Component Input / Output (B-Tag Frame) B-VID Port number Virtual output port number or physical output port number B-DA Backbone Destination MAC Address I-SID Local I-SID B-VID Replace B-VID Flow ID Flow number direction I-Component Input / I-Component Output
B-Component Input / B-Component Output Component id Unrecognized I-Components
C-VLAN Aware I-Component
S-VLAN Aware I-Component
B-component Valid 1 (valid) / 0 (free)

In addition, the port table 500 is a table newly introduced in the present invention to indicate the mapping relationship between the virtual port and the physical port, and has a configuration as shown in Table 6. Here, the T-component ID field is used to indicate whether to convert the frame format when outputting the frame.

Field name Explanation Virtual port Virtual Output Port Number / Virtual Input Port Number VLAN ID I-Component Input / Output (C-Tag Frame) C-VID I-Component Input / Output (S-Tag Frame) S-VID B-Component Input / Output (B-Tag Frame) B-VID Physical
port Physical output port number
Physical input port number Flow ID Flow number direction I-Component Input / I-Component Output
B-Component Input / B-Component Output Component id Unrecognized I-Components
C-VLAN Aware I-Component
S-VLAN Aware I-Component
B-component T-Component ID Translated component ID Valid 1 (valid) / 0 (free)

5A to 5D are detailed structural diagrams of a packet forwarding layer according to another embodiment of the present invention. FIG. 5A is a detailed structure of an I-component input unit, FIG. 5B is a detailed structure of a B-component input unit, and FIG. 5C is a B -Detailed structure of the component output section, and FIG. 5D shows the detailed structure of the I-component output section.

5A to 5D, unlike the embodiment illustrated in FIGS. 4A to 4D, only the component ID is introduced without introducing the concept of a virtual port. Accordingly, the present invention has a configuration different from that of the above-described embodiment, and will be mainly described below.

Referring to FIG. 5A, the I-component input unit 110 does not include an unrecognized I-component search unit for allocating a component ID and a VLAN ID to an untagged frame, and provides the C-VLAN-aware I-component search unit. (113) is in charge. In addition, the I-component input unit 110 outputs a frame through a physical port (PIP), not a virtual port.

Specifically, the frame classifier 112 classifies the frame according to the format using the TPID value extracted from the input frame, and then the C-tag frame and the untag frame are the C-VLAN recognition I-component search unit 113. And the S-tag frame to the S-VLAN aware I-component searcher 115.

The C-VLAN aware I-component searcher 113 receives the C-tag frame from the frame classifier 112 and assigns the C-VLAN aware I-component to the component ID. In addition, the C-VLAN aware I-component searcher 113 receives an untagged frame from the frame classifier 112, assigns an unrecognized I-component as a component ID, and assigns a default VLAN ID to the C-VID. . Thereafter, the C-VLAN aware I-component search unit 113 searches the filtering table 200 using the C-DA, C-VID, and component ID to convert the C-tag frame into an I-tag frame. Obtain the required B-DA, B-SA, local I-SID, and physical output port (PIP) information.

The S-VLAN aware I-component searcher 115 receives the S-tag frame from the frame classifier 112 and assigns the S-VLAN aware I-component to the component ID. Subsequently, the S-VLAN aware I-component search unit 115 searches the filtering table 200 by using the C-DA, S-VID, and component ID to convert the S-tag frame into an I-tag frame. Obtain the required B-DA, B-SA, local I-SID, and physical output port (PIP) information.

The I-tag encapsulation unit 116 receives a C-tag frame or an S-tag frame from the C-VLAN aware I-component searcher 113 and the S-VLAN aware I-component searcher 115, and filters the table. After generating the I-tag using the information obtained by searching for 200, the generated I-tag is tagged (ie, encapsulated) in the received frame and then output through the physical port 117.

Referring to FIG. 5B, the B-component input unit 120 receives an I-tag frame through the physical CBP port 121 and outputs a B-tag frame through the physical PNP port 127. There is a difference from the above-described embodiment described with reference to. Accordingly, unlike the above-described embodiment, the B-component input unit 120 according to the present embodiment does not need a frame tag switching / integrating unit for mapping virtual port information and physical port information.

Referring to FIG. 5C, the B-component output unit 130 is different from the above-described embodiment described with reference to FIG. 4C in that the I-tag frame is output through the physical CBP port 134.

Referring to FIG. 5D, the I-component output unit 140 is different from the above-described embodiment described with reference to FIG. 4D in that a frame is input through a physical port (PIP) rather than a virtual port.

In detail, the I-tag removing unit 142 removes the I-tag from the I-tag frame input through the PIP port 141 and transmits the I-tag to the frame classifying unit 143.

The frame classifier 143 extracts the TPID value, the VLAN ID, and the C-DA of the tag from the received frame, classifies the frame according to the format using the TPID value, and the C-tag frame recognizes the C-VLAN. To the component retrieval unit 144, the S-tag frame is transmitted to the S-VLAN aware I-component retrieval unit 146.

The C-VLAN aware I-component searcher 144 receives the C-tag frame from the frame classifier 143 and assigns the C-VLAN aware I-component to the component ID. Thereafter, the C-VLAN aware I-component searcher 144 searches the filtering table 200 using the C-DA, C-VID, and component ID to obtain output port (CNP) information and to determine the corresponding output port. Output frames through

The S-VLAN aware I-component searcher 146 receives the S-tag frame from the frame classifier 143 and assigns the S-VLAN aware I-component to the component ID. Subsequently, the S-VLAN aware I-component searcher 146 searches the filtering table 200 by using the C-DA, S-VID, and component ID, thereby obtaining output port (CNP) information and obtaining the corresponding output port. Output frames through

6A to 6E are flowcharts illustrating a packet processing process according to the present invention, in which FIG. 6A illustrates a process performed by an I-component input unit, FIG. 6B illustrates a process performed by a B-component input unit, and FIG. 6C illustrates a B-component output. The processing in the unit is shown, and FIGS. 6D and 6E show the processing in the I-component output unit.

Referring to FIG. 6A, when frames of different formats are input through the CNP port (S10), the frame classifier 112 extracts a tag type (TPID), VLAN ID, and C-DA from the input frame (S11). ).

Thereafter, the input frame is classified according to the format using the TPID value. If the TPID value is 88a8 (S12), the frame is classified as an S-tag frame and an S-VLAN recognition I-component is given as a component ID (S13). Subsequently, the S-VLAN aware I-component search unit 115 searches the filtering table 200 using the C-DA, S-VID, and component ID to search for the B-DA, B-SA, local I-SID, and virtual. Obtain output port information (S14).

On the other hand, if the TPID value is 8100 (S15), it is classified as a C-tag frame, and a C-VLAN recognition I-component is assigned as a component ID (S16). A non-identified I-component is assigned and a default VLAN ID is assigned to the C-VID (S18). Subsequently, the C-VLAN aware I-component search unit 113 searches the filtering table 200 using the C-DA, C-VID, and component ID to search for the B-DA, B-SA, local I-SID, and virtual. Obtain output port information (S19).

Thereafter, the I-tag encapsulation unit 116 generates an I-tag using B-DA, B-SA, and a local I-SID, and encapsulates the input frame into the I-tag (S20). The I-tag frame is output through the output ports 117 and 118 (S21).

Referring to FIG. 6B, when an I-tag frame is input through the virtual ports 121 and 122 (S30), the B-component search unit 123 may detect a local I-SID and a B-DA from the input I-tag frame. Extract (S31).

Subsequently, the B-component search unit 123 searches the service instance table 300 using the local I-SID to obtain the backbone I-SID and B-VID (S32), and obtains the B-DA and B-VID. The filtering table 200 is searched to obtain virtual output port information (S33).

Thereafter, the B-tag encapsulation unit 124 replaces the local I-SID of the I-tag frame received from the virtual port with the backbone I-SID obtained from the B-component searcher 123, and then replaces the B-tag. It generates and encapsulates the I-tag frame into the B-tag (S34).

Subsequently, the frame tag switching / integrating unit 126 searches for the port table 500 using the virtual output port information to obtain physical output port (PNP) information (S35), and then uses B through the physical output port. The tag frame is output to the backbone core network (S36).

Referring to FIG. 6C, when a B-tag frame is input through the PNP port 131 (S40), the B-component search unit 132 may perform a backbone I-SID, B-DA, and B- in the input B-tag frame. The VID is extracted (S41).

Subsequently, the B-component search unit 132 searches the filtering table 200 using the B-DA and the B-VID to obtain virtual output port (VIP) information (S42), and uses the backbone I-SID. The service instance table 300 is searched to obtain a local I-SID (S43).

Thereafter, the B-tag removing unit 133 replaces the backbone I-SID of the B-tag frame received from the PNP port with a local I-SID obtained from the B-component search unit 132, and then receives the received B- tag. The B-tag is removed from the tag frame and converted into an I-tag frame (S44), and then an I-tag frame is output through the virtual output port 134 (S45).

6D and 6E, when an I-tag frame is input through the VIP port 141 (S50), the I-tag removing unit 142 removes the I-tag from the input I-tag frame ( S51) and transfers to the frame classification unit 143.

Thereafter, the frame classifier 143 extracts a tag type (TPID value), a VLAN ID, and a C-DA from the I-tag frame (S52), and classifies the frame according to a format using the TPID value.

Specifically, if the TPID value is 88a8 (S53), the STP tag is classified as an S-tag frame and an S-VLAN recognition I-component is assigned to the component ID (S54). Thereafter, the S-VLAN aware I-component searcher 146 searches the filtering table 200 using the C-DA, S-VID, and component ID to obtain virtual output port information (S55).

On the other hand, if the TPID value is 8100 (S56), it is classified as a C-tag frame and gives a C-VLAN aware I-component as a component ID (S57). Thereafter, the C-VLAN aware I-component searcher 144 searches for the filtering table 200 using the C-DA, C-VID, and component ID to obtain virtual output port information (S58).

Thereafter, the frame tag switching / integrating unit 148 searches the port table 500 using the virtual output port information to obtain a default VLAN ID, a component ID, a T-component ID, and corresponding output port (CNP) information ( S60).

Thereafter, the frame tag switching / integrating unit 148 appropriately converts the format of the received frame according to the component ID and the T-component ID and outputs the result through the output port 149.

Specifically, when the T-component ID is 0 regardless of the frame format (S62, S67), the frame is output through the output port CNP without changing the frame format (S71).

On the other hand, when the component ID is an S-VLAN aware I-component (S61), if the T-component ID is a C-VLAN aware I-component (S63), the S-tag frame is converted into a C-tag frame with the default C-VID. If the T-component ID is not a C-VLAN-aware I-component, the T-component ID corresponds to an unrecognized I-component, and the S-tag is deleted to be converted into an untagged frame and output.

On the other hand, if the component ID is a C-VLAN aware I-component (S66), if the T-component ID is an S-VLAN aware I-component (S68), the C-tag frame is converted to the S-tag frame with the default S-VID. If the T-component ID is not an S-VLAN-aware I-component, the T-component ID corresponds to an unrecognized I-component, the C-tag is deleted, converted into an untagged frame, and then output.

The present invention is not limited to the above-described embodiments and the accompanying drawings. It will be apparent to those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

1 is a structural diagram of a conventional packet delivery layer to which the PBB-TE technology is applied;

2A to 2D are diagrams illustrating a frame format for each tag type;

3 is a structural diagram of a packet forwarding layer according to an embodiment of the present invention;

4A to 4D are detailed structural diagrams of a packet forwarding layer according to an embodiment of the present invention;

5A through 5D are detailed structural diagrams of a packet forwarding layer according to another embodiment of the present invention, and

6A to 6E are flowcharts illustrating a packet processing process according to the present invention.

Claims (9)

Receives frames of different formats through one CNP (Customer Network Port) port, assigns a component ID according to the format of the received frames, and then encapsulates the received frames into I-tags and outputs them through the virtual output port. An I-component input unit; A B-component input unit encapsulating an I-tag frame received from the I-component input unit through a virtual input port into a B-tag and outputting the same through a PNP (Provider Network Port) port; A B-component output unit which removes the B-tag from the B-tag frame received through the PNP port, converts the B-tag into an I-tag frame, and outputs the same through the virtual output port; And After removing the I-tag from the I-tag frame received from the B-component output unit through the virtual input port, assigning a component ID according to the format of the frame, and a T-component ID indicating whether to convert the component ID and the frame format. And an I-component output unit for converting a format of a frame according to a value and outputting the same through a CNP port. The method of claim 1, wherein the I-component input unit, Classify the frame received through the CNP port according to the frame format and transfer the frame to any one of the C-VLAN-aware I-component searcher, an unrecognized I-component searcher, and an S-VLAN-aware I-component searcher. part; Receives a C-tag frame from the frame classifier and gives a C-VLAN aware I-component as a component ID, receives a C-tag frame tagged with a default VLAN ID from the unrecognized I-component searcher, and filters it. A C-VLAN aware I-component searcher for searching the table to obtain virtual output port information; An unrecognized I-component retrieval unit which receives an untagged frame from the frame classifier and assigns an unrecognized I-component to a component ID and allocates a default VLAN ID to a C-VID; An S-VLAN aware I-component searcher which receives an S-tag frame from the frame classifier and assigns an S-VLAN aware I-component as a component ID, and searches the filtering table to obtain virtual output port information; And Generating an I-tag and including an I-tag encapsulation unit for tagging the I-tag in a frame received from the C-VLAN aware I-component searcher or the S-VLAN aware I-component searcher. Packet forwarding layer device. The method of claim 1, wherein the B-component input unit, A B-component retrieval unit for retrieving a filtering table to obtain virtual output port information for the I-tag frame; A B-tag encapsulation unit generating a B-tag, tagging the B-tag on an I-tag frame received from the B-component searcher, and outputting the B-tag through a virtual output port; And A frame tag switching / integrating unit for retrieving a port table to obtain physical output port information corresponding to the virtual output port, and then outputting a B-tag frame received from the B-tag encapsulation unit through the physical output port. Packet forwarding layer device comprising a. The method of claim 1, wherein the B-component output unit, A B-component retrieval unit for retrieving a filtering table to obtain virtual output port information for the B-tag frame; And And a B-tag removing unit which removes the B-tag from the B-tag frame received from the B-component searcher and outputs the same through the virtual output port. The method of claim 1, wherein the I-component output unit, An I-tag removing unit removing an I-tag from the received I-tag frame; A frame classifying unit classifying the frame received from the I-tag removing unit according to a frame format and transmitting the classified frame to a C-VLAN aware I-component searcher or an S-VLAN aware I-component searcher; A C-VLAN aware I-component searcher for receiving a C-tag frame from the frame classifier and assigning a C-VLAN aware I-component to a component ID and searching for a filtering table to obtain virtual output port information; An S-VLAN aware I-component searcher which receives an S-tag frame from the frame classifier and assigns an S-VLAN aware I-component as a component ID, and searches the filtering table to obtain virtual output port information; And Receive a C-tag frame or an S-tag frame from the C-VLAN aware I-component searcher or the S-VLAN aware I-component searcher, and search the port table for T-component ID and physical output port information. And a frame tag switching / integrating unit for obtaining and converting and outputting a format of a frame according to a component ID and a T-component ID value. The method of claim 5, wherein the frame tag switching / integration unit, If the T-component ID is 0, the T-component ID is output without changing the frame format. When the component ID is an S-VLAN aware I-component, if the T-component ID is a C-VLAN aware I-component, the T-component ID is converted into a C-tag frame and outputted. The T-component ID is a C-VLAN aware I-component. If it is not a component, it is converted to an untagged frame and output. If the component ID is a C-VLAN aware I-component, if the T-component ID is an S-VLAN aware I-component, the T-component ID is converted into an S-tag frame and outputted. The T-component ID is an S-VLAN recognition I. The packet forwarding layer device, characterized in that for converting to an untagged frame if it is not a component. The method according to any one of claims 2 to 5, The filtering table includes a component ID field and has a physical output port or virtual output port information in a port number field. The method according to any one of claims 2 to 5, And a component ID as a search factor for searching the filtering table. The method according to claim 3 or 5, The port table stores a mapping relationship between a virtual output port and a physical output port, and includes a T-component ID field indicating whether to convert a frame format.

Images