WO2018177273A1

WO2018177273A1 - Method and apparatus for processing based on bier information

Info

Publication number: WO2018177273A1
Application number: PCT/CN2018/080610
Authority: WO
Inventors: 徐本崇; 张征
Original assignee: 中兴通讯股份有限公司
Priority date: 2017-03-28
Filing date: 2018-03-27
Publication date: 2018-10-04
Also published as: CN108667731A

Abstract

Disclosed is a method, unrelated to a protocol, for processing bit indexed explicit replication (BIER) information. The method comprises: based on a first protocol mechanism, using BIER information to generate a message; sending the generated message, wherein the BIER information is used to generate a BIER protocol table and a BIER forwarding table; the BIER protocol table and the BIER forwarding table are entries generated by means of using the BIER information combined with a unicast routing table; and the first protocol mechanism is a protocol mechanism, unrelated to a unicast protocol, for transmitting the BIER information. Also disclosed at the same time is an apparatus for processing BIER information.

Description

Processing and device based on BIER information

Technical field

The present disclosure relates to the field of communications, and in particular, to a method and apparatus for processing BIER (Bit Index Explicit Replication) information.

Background technique

After the use of Internet Protocol (IP) to achieve multicast forwarding, BIER technology has slowly begun to develop. Since the BIER technique can reduce the amount of data of state information stored at the node, it has become a focus of attention.

Summary of the invention

The following is an overview of the topics detailed in this document. This Summary is not intended to limit the scope of the claims.

Embodiments of the present disclosure provide a method and apparatus for processing BIER information that is independent of a protocol.

The embodiment of the present disclosure provides a method for processing BIER information that is not related to a protocol, and the method includes:

Generating a message using the BIER information based on the first protocol mechanism;

Send the generated message; among them,

The BIER information is used to generate a BIER forwarding routing table; the BIER forwarding routing table is a forwarding routing table generated by using the BIER information and combined with a unicast routing table; the first protocol mechanism is used for transmitting BIER information, and A protocol mechanism that is independent of the unicast protocol.

In an exemplary embodiment, the generating a message using the BIER information based on the first protocol mechanism includes one of the following:

The first packet is generated by using the BIER information according to an extended protocol independent protocol (PIM) protocol.

Generating a second packet by using the BIER information based on the IP mechanism; when the source IP address and the ingress port IP number of the second packet meet the next hop and the outbound port IP number of the unicast routing table, the second The message is received;

The third packet is generated by using the BIER information according to the User Datagram Protocol (UDP) mechanism; the source IP address and the ingress port UDP number of the third packet are in accordance with the next hop and the outbound UDP number of the unicast routing table. The third message is received;

The fourth packet is generated by using the BIER information according to the Transmission Control Protocol (TCP) mechanism; when the source IP address of the fourth packet, the TCP number of the ingress port, and the next hop of the unicast routing table and the TCP number of the egress port are met. The fourth message is received.

In an exemplary embodiment, the generating, according to the extended PIM protocol mechanism, the first message by using the BIER information, including:

Generating a first BIER advertisement message based on the PIM protocol by using the BIER information; the first BIER advertisement message includes information for implementing packet forwarding encapsulated in the BIER format; the first BIER advertisement message is used to notify the corresponding BIER information for BIER equipment.

Generating a first BIER management message based on the PIM protocol by using the BIER information; the first BIER management message includes information for implementing packet forwarding encapsulated in the BIER format; the first BIER advertisement message is used to notify the network BIER information for all BIER devices.

In an exemplary embodiment, before generating the BIER management message, the method further includes:

Generating a second BIER management message based on the PIM protocol;

Sending the second BIER management message; the second BIER management message is used to elect a BIER device manager in the network.

Using the BIER information, generating a second BIER advertisement message based on the PIM protocol, and generating a type, length, and value (TLV) of the second BIER advertisement message; the second BIER advertisement message includes a BIER format encapsulation Message forwarding information; the second BIER advertisement message and the TLV are used to notify the BIER information of the corresponding BIER device;

Correspondingly, the second BIER advertisement message and the TLV are sent.

In an exemplary embodiment, the method further includes:

Generate a PIM hello packet based on the PIM protocol.

The PIM hello message is sent; the PIM hello message is used to notify the BIER capability of the BIER device.

In an exemplary embodiment, the second message includes information for implementing packet forwarding of the BIER format encapsulation; the second message is used to advertise BIER information of all BIER devices in the network.

In an exemplary embodiment, the third message includes information for implementing packet forwarding of the BIER format encapsulation; the third message is used to advertise BIER information of all BIER devices in the network.

In an exemplary embodiment, the fourth packet includes information for implementing packet forwarding of the BIER format encapsulation; the fourth packet is used to advertise BIER information of all BIER devices in the network.

In an exemplary embodiment, when the second packet, the third packet, or the fourth packet is sent, the packet is sent in one of the following manners:

Sending packets in unicast mode;

Sends packets in broadcast or multicast mode.

The embodiment of the present disclosure further provides a method for processing BIER information that is not related to a protocol, including:

Receiving a message; the received message is transmitted based on the first protocol mechanism;

Parsing the message to obtain BIER information;

Generating a BIER forwarding routing table based on the obtained BIER information and combining the unicast routing table;

The first protocol mechanism is a protocol mechanism for transmitting BIER information and independent of the unicast protocol.

In an exemplary embodiment, the received message; the received message is transmitted based on a first protocol mechanism; and the message is parsed to obtain BIER information, including one of the following:

Receiving the first packet; parsing the first packet according to the extended PIM protocol mechanism to obtain BIER information;

Receiving the second packet when the source IP address and the inbound port IP address of the second packet match the next hop and the outbound port IP number of the unicast routing table; and parsing the second packet based on the IP mechanism , get BIER information;

The third packet is received when the source IP address and the inbound port UDP number of the third packet match the next hop and the outbound UDP number of the unicast routing table. The third packet is parsed based on the UDP mechanism. , get BIER information;

Receiving the fourth packet when the source IP address and the ingress port TCP number of the fourth packet match the next hop and the outbound TCP number of the unicast routing table; and parsing the third packet based on the TCP mechanism , get BIER information.

In an exemplary embodiment, the first packet is a first BIER advertisement message;

Correspondingly, the first BIER advertisement message is parsed to obtain information for implementing packet forwarding of the BIER format encapsulation; and the first BIER advertisement message is used to notify the BIER information of the corresponding BIER device.

In an exemplary embodiment, the first packet is a first BIER management packet;

Correspondingly, the first BIER management packet is parsed to obtain information for implementing packet forwarding of the BIER format encapsulation; and the first BIER advertisement packet is used to notify BIER information of all BIER devices in the network.

In an exemplary embodiment, before receiving the first BIER management message, the method further includes:

Receiving a second BIER management message;

Parsing the second BIER management message based on the PIM protocol to obtain candidate BIER manager related information;

The BIER device manager in the network is elected using the candidate BIER manager related information.

In an exemplary embodiment, the first packet is a second BIER advertisement packet;

When the second BIER advertisement message is received, the method further includes:

Receiving a TLV of the second BIER notification message;

The TLV and the BIER advertisement message are parsed, and the information for forwarding the packet in the BIER format encapsulation is obtained. The second BIER advertisement message and the TLV are used to notify the BIER information of the corresponding BIER device.

In an exemplary embodiment, the method further includes:

Receive a PIM hello message;

By analyzing the PIM hello message based on the PIM protocol, the BIER capability of the BIER device is known.

In an exemplary embodiment, the second packet is parsed to obtain information for implementing packet forwarding of the BIER format encapsulation; and the second packet is used to advertise BIER information of all BIER devices in the network.

In an exemplary embodiment, the third packet is parsed to obtain information for implementing packet forwarding of the BIER format encapsulation; and the third packet is used to advertise BIER information of all BIER devices in the network.

In an exemplary embodiment, the fourth packet is parsed to obtain information for implementing packet forwarding of the BIER format encapsulation; and the fourth packet is used to advertise BIER information of all BIER devices in the network.

The embodiment of the present disclosure further provides a processing device based on BIER information, including:

a first generating unit, configured to generate a message by using BIER information based on a first protocol mechanism;

a sending unit, configured to send the generated message; wherein

In an exemplary embodiment, the first generating unit is configured to implement one of the following:

Generating the first packet by using the BIER information based on the extended PIM protocol mechanism;

The third packet is generated by using the BIER information based on the UDP mechanism; when the source IP address of the third packet, the UDP number of the ingress port, and the next hop of the unicast routing table, the UDP number of the outbound port, the third The message is received;

The fourth packet is generated by using the BIER information according to the TCP mechanism. When the source IP address of the fourth packet, the TCP number of the ingress port, and the next hop of the unicast routing table, and the outgoing port TCP number, the fourth packet is used. The message was received.

Receiving and parsing unit, configured to receive a message; the received message is transmitted according to a first protocol mechanism; and parsing the message to obtain BIER information;

a second generating unit, configured to generate a BIER forwarding routing table based on the obtained BIER information and in combination with the unicast routing table;

In an exemplary embodiment, the receiving and parsing unit is configured to implement one of the following:

Embodiments of the present disclosure also provide a computer readable storage medium storing computer executable instructions that, when executed by a processor, implement any of the methods described above.

The method and device for processing BIER information related to the protocol provided by the embodiment of the present disclosure generates a message by using the BIER information based on the first protocol mechanism; sends the generated message; receives the message; and receives the received message based on the first The protocol mechanism performs transmission; parses the message to obtain BIER information; and generates a BIER forwarding routing table based on the obtained BIER information and in combination with the unicast routing table; wherein the first protocol mechanism is used for transmitting BIER information, and A protocol mechanism that is independent of the unicast protocol, that is, the BIER information is transmitted through a protocol mechanism independent of the unicast protocol. When performing BIER topology calculation, any unicast routing table can be used instead of relying on some unicast protocol. That is, there is no requirement for unicast, so that it can get rid of the BIER technology's dependence on the specific unicast protocol, and it does not need unicast to support the BIER function for the BIER extension. Therefore, it is easy to promote the BIER technology.

Other aspects will be apparent upon reading and understanding the drawings and detailed description.

DRAWINGS

1 is a schematic flow chart of a protocol-independent BIER information processing method according to Example 1 of the present disclosure;

2 is a schematic flow chart of another protocol-independent BIER information processing method according to Example 1 of the present disclosure;

3 is a schematic diagram of a networking mode according to an embodiment of the present disclosure;

4 is a schematic structural diagram of a BIER advertisement packet according to an embodiment of the present disclosure;

5 is a schematic structural diagram of a BIER MPLS encapsulation subtype according to an embodiment of the present disclosure;

FIG. 6 is a schematic structural diagram of a BIER option of a PIM hello message according to an embodiment of the present disclosure;

FIG. 7 is a schematic structural diagram of a BIER management packet according to an embodiment of the present disclosure;

8 is a schematic diagram of a transmission direction of a message in a candidate BIER manager discovery process according to an embodiment of the present disclosure;

FIG. 9 is a schematic diagram of a process for another node to send its own BIER information to a BIER manager according to an embodiment of the present disclosure;

10 is a schematic structural diagram of a BIER advertisement message according to an embodiment of the present disclosure;

11 is a schematic structural diagram of a BIER information subtype according to an embodiment of the present disclosure;

12 is a schematic structural diagram of a processing apparatus based on BIER information according to an embodiment of the present disclosure;

FIG. 13 is a schematic structural diagram of another apparatus for processing BIER information according to an embodiment of the present disclosure.

detailed description

Currently, BIER information is mainly carried based on the extension of unicast protocols such as Intermediate System to Intermediate System (ISIS) or Open Shortest Path First (OSPF), so that each unicast protocol is required to carry this unicast protocol. The expansion of BIER information is not flexible. In addition, existing standards cannot support all unicast protocols, such as routing information protocol (RIP), static routing, and so on. When there is only RIP or static routing protocol in the network, the BIER information cannot be used because there is no way to transmit it. Moreover, in a multicast deployment, there are often scenarios in which different unicast protocols are interconnected. Currently, such a scenario cannot apply BIER technology in such a scenario. In summary, the transmission of BIER information depends on the specific unicast protocol, which limits the application of BIER technology.

The present disclosure will be further described in detail below with reference to the accompanying drawings and embodiments.

Multicasting refers to the delivery of multicast data packets (typically including data packets identifying information about a multicast group (eg, multicast group address)) from a source to multiple recipients without overwhelming the source. burden. As used herein, the recipient refers to a host (eg, a computing device or application) that has subscribed to an anchor group. In multicast technology, instead of copying a multicast data packet from a source and transmitting a copy of the multicast data packet to each receiver, a single copy of the multicast group data packet is sent by the source and multicast is enabled (multicast-enabled) The router replicates the packet at the point(s) of the path forked to each recipient.

Various routing protocols, such as IP, are used in multicast technology. IP-based multicast technology has become an IP multicast technology. Then, with the development of technology, in order to reduce the amount of data of state information stored at the node, a BER technique is proposed. In the BIER technique, recipient information is attached to a packet in the form of bits, and the packet is forwarded based on the recipient information. For example, the location of the bit is used as an index into the forwarding table, and the packet is copied to the designated node. Because of its characteristics, BIER technology can also be called "stateless multicast."

Currently, the transmission of BIER information must rely on a specific unicast protocol, which limits the application of BIER technology.

Based on this, in various embodiments of the present disclosure: the unicast routing protocol is not extended, and the BIER information is transmitted using a transmission mode independent of the unicast protocol.

Example one

An embodiment of the present disclosure provides a method for processing BIER information that is not related to a protocol. As shown in FIG. 1, the method includes the following steps:

Step 101: Generate a message by using BIER information based on the first protocol mechanism.

Step 102: Send the generated message.

The BIER information is used to generate a BIER forwarding routing table. The BIER forwarding routing table is a forwarding routing table generated by using the BIER information and combined with a unicast routing table. The first protocol mechanism is used to transmit BIER information. And a protocol mechanism that is not related to the unicast protocol.

In practical applications, the PIM protocol can be extended to transmit BIER information.

Based on this, in an embodiment, the specific implementation of step 101 includes:

The first message is generated by using the BIER information based on the extended PIM protocol mechanism.

Here, the extended PIM protocol mechanism generates a first packet by using BIER information, including:

The BIER device uses the BIER information to generate a first BIER advertisement message based on the PIM protocol; the first BIER advertisement message includes information for implementing packet forwarding encapsulated in the BIER format; the first BIER advertisement message is used for Announce the BIER information corresponding to the BIER device.

Here, the BIER device refers to a device that supports BIER forwarding capability.

In the actual application, some attribute information of the BIER advertisement message may not be included in the message, but is embodied in a separate manner.

Based on this, the extended PIM protocol mechanism generates the first packet by using the BIER information, including:

Using the BIER information, generating a second BIER advertisement message based on the PIM protocol, and generating a TLV of the second BIER advertisement message; the second BIER advertisement message includes information for implementing packet forwarding of the BIER format encapsulation; The second BIER advertisement message and the TLV are used to notify the BIER information of the corresponding BIER device;

Correspondingly, the second BIER advertisement message and the TLV are sent.

In addition, BIER management messages can also be used to transmit BIER information.

The BIER device manager uses the BIER information to generate a first BIER management message based on the PIM protocol; the first BIER management message includes information for implementing packet forwarding encapsulated in the BIER format; the first BIER advertisement message Used to inform BIER information for all BIER devices in the network.

Here, since the BIER device manager generates the first BIER management message to announce the BIER information of all BIER devices in the network. So first choose the BIER device manager in the network.

Based on this, in an embodiment, the candidate BIER device manager in the network generates a second BIER management message based on the PIM protocol; and sends the second BIER management message; the second BIER management message is used for Elect the BIER device manager in the network.

Specifically, after receiving the second BIER management message flooded by all candidate BIER device managers, the BIER device in the network selects according to the priority of each candidate BIER device manager carried in the second BIER management message. The BIER device manager, when the priorities are the same, selects the BIER device manager by the IP address of each candidate BIER device manager carried in the second BIER management message.

After the transmission device manager is elected, the other BIER devices send their own BIER information to the transmission device manager through the BIER advertisement message, so that the transmission device manager summarizes the BIER information of all the transmission devices and advertises the BIER management message.

In actual application, in the solution for extending the PIM protocol, it is necessary to know whether the device in the network has the BIER capability, that is, whether the BIER forwarding capability is supported. In this case, you can use the PIM hello message.

Based on this, in an embodiment, the method further includes:

Generate a PIM hello packet based on the PIM protocol.

In practical applications, BIER information can be transmitted based on IP, TCP or UDP.

Based on this, in an embodiment, the generating the message by using the BIER information based on the first protocol mechanism includes one of the following:

The BIER device manager generates a second packet by using the BIER information based on the IP mechanism. When the source IP address and the ingress port IP number of the second packet match the next hop and the outbound port IP number of the unicast routing table, The second message is received;

The BIER device manager generates a third packet by using the BIER information based on the UDP mechanism. When the source IP address and the ingress port UDP number of the third packet match the next hop and the outbound port UDP number of the unicast routing table, The third message is received;

The BIER device manager generates a fourth packet by using the BIER information based on the TCP mechanism. When the source IP address of the fourth packet and the TCP number of the ingress port meet the next hop of the unicast routing table and the TCP number of the egress port, The fourth message is received.

The second packet includes information for implementing packet forwarding in a BIER format encapsulation; the second packet is used to advertise BIER information of all BIER devices in the network.

The third packet includes information for implementing packet forwarding of the BIER format encapsulation; the third packet is used for advertising BIER information of all BIER devices in the network.

The fourth packet includes information for implementing packet forwarding of the BIER format encapsulation; and the fourth packet is used for advertising BIER information of all BIER devices in the network.

In practical applications, the BIER device manager is generated by static configuration.

In the embodiment of the disclosure, the information used to implement packet forwarding in the BIER format encapsulation may include all or part of the following information: subdomain ID (Bid-id), BIER device ID (BFR-id), BIER device IP. Address (BFR-Prefix), bit length (BSL, Bit String Length), tag information (Lable), etc.

Correspondingly, the embodiment of the present disclosure further provides another method for processing BIER information that is not related to the protocol. As shown in FIG. 2, the method includes:

Step 201: Receive a message; the received message is transmitted according to a first protocol mechanism;

Step 202: Parse the packet to obtain BIER information.

Step 203: Generate a BIER forwarding routing table based on the obtained BIER information and in combination with the unicast routing table.

Based on this, in an embodiment, steps 201-202 specifically include:

Receiving the first packet; parsing the first packet according to the extended PIM protocol mechanism to obtain BIER information.

The first packet is a first BIER advertisement packet;

Based on this, the first packet is a second BIER advertisement packet;

Receiving a TLV of the second BIER notification message;

Based on this, the first packet is a first BIER management packet;

Based on this, in an embodiment, the method may further include:

Receiving a second BIER management message;

Based on this, in an embodiment, the method further includes:

Receive a PIM hello message;

Based on this, when the BIER information is transmitted in an IP-based manner, the second packet is parsed to obtain information for implementing packet forwarding in the BIER format encapsulation; the second packet is used to notify all BIER devices in the network. BIER information.

When the BIER information is transmitted in a UDP-based manner, the third packet is parsed to obtain information for forwarding the packet encapsulated in the BIER format, and the third packet is used to notify the BIER information of all BIER devices in the network. .

When the BIER information is transmitted in a TCP-based manner, the fourth packet is parsed to obtain information for implementing packet forwarding in the BIER format encapsulation; and the fourth packet is used to advertise BIER information of all BIER devices in the network. .

As can be seen from the above description, the solution provided by the embodiment of the present disclosure may extend the existing PIM protocol, or use a more reliable TCP/UDP link to carry the BIER information and advertise in the network. . The routing of the BIER edge node (the next hop to the BIER edge node) can be either a normal static route or a topology calculated using a unicast protocol, and there is no special requirement for unicast.

The protocol-independent BIER information processing method provided by the embodiment of the present disclosure generates a message by using the BIER information based on the first protocol mechanism; sends the generated message; receives the message; and the received message is based on the first protocol mechanism. Transmitting the packet to obtain BIER information; and generating a BIER forwarding routing table based on the obtained BIER information and combining the unicast routing table; wherein the first protocol mechanism is for transmitting BIER information and is unicast Protocol-independent protocol mechanism, that is, the BIER information is transmitted through a protocol mechanism independent of the unicast protocol. When performing BIER topology calculation, any unicast routing table can be used instead of relying on some unicast protocol, that is, Unicast has no feature requirements, so it can get rid of the BIER technology's dependence on specific unicast protocols. It does not need unicast to support BIER function for BIER extension. Therefore, it is easy to promote BIER technology.

In addition, the BIER information is carried in a UDP or TCP link and is advertised in the network. Thus, the reliability of the transmission can be increased.

Example two

Based on the first example, this example describes in detail the process of extending the PIM protocol to transmit BIER information.

In this example, the networking mode is as shown in Figure 3. There are multiple nodes in the network, and the unicast protocols are not running on these multiple nodes. Instead, unicast routes are formed by configuring static routes on each node. table. Therefore, according to the current implementation scheme, the BIER information cannot be transmitted in such a network, and therefore the network cannot forward the BIER message.

In this example, the BIER information can be delivered in the network in a manner that is extended by the PIM protocol.

In the PIM protocol extension mode, you need to add a PIM packet type, a new BIER MPLS encapsulation subtype, and a new BIER Hello option. Specifically include:

First, add a PIM packet type-BIER advertisement packet.

As shown in Figure 4, the fields of the BIER advertisement packet include: PIM version (PIM Ver), reserved field (Reserved), checksum (Checksum), type (Type), subtype number (Sub Type Num), and hold. Holdtime, Reserved1, Subdomain-id, BFR-id, BFR-Prefix, Sub Type, Length, and Subtype Sub Type Value. among them,

The PIM version (PIM Ver), reserved field (Reserved), and checksum (Checksum) descriptions are consistent with the definitions in RFC4601.

Type: This embodiment of the present disclosure does not limit this, and may be any one of the currently undefined PIM message option types.

Sub Type Num: A packet can carry multiple subtypes. This field is the number of subtypes carried. 1 byte in length.

Holdtime: The time the information is to be saved; in practice, the default 210s can be set. 1 byte in length.

Reserved field (Reserved1): Enter 0 by default.

Subdomain-id: A unique value that represents the subdomain of the BIER. 1 byte in length.

BFR number (BFR-id): 2 bytes in length. If there is no BFR-id, it is set to an illegal value.

BFR-prefix: Uniquely identifies the value of the device. The format of the Encoded-Unicast format is different according to IPv4 and IPv6. For details, see the relevant section of RFC4601.

Sub Type: Defined for BIER related subtypes, extensible. 1 byte in length.

Length: Length that is variable (that is, the content is changed), the value of the subtype value. 1 byte in length.

Sub Type Value: The value of the subtype.

Second, add the BIER MPLS encapsulation subtype

As shown in Figure 5, the fields of the BIER MPLS encapsulation subtype include:

Sub Type: The embodiment of the present disclosure does not limit this, for example, 1;

Lbl Range Size: The label range, which is used to encapsulate the length of the sub-domain and the bitstring, and has a length of 1 byte.

Bit length (BS Len, Bitstring Length): length of this field, 4 bits (bit);

Lable: The starting tag of the tag range, 20 bits in length.

Third, add PIM hello message BIER option

As shown in Figure 6, the fields of the new BIER Hello option include:

Option type: To be determined, can be any unused option type;

The length and value are not limited, and the length may be 0, and no value is carried; in the embodiment of the present disclosure, it may be defined as 4, and this option represents the BIER forwarding capability.

The transmission of the BIER information and the topology establishment process are described in detail below.

Taking node 2 as an example, the BIER information of node 2, including: BFR-prefix information, sub-domain-id information, BSL information, etc., can be implemented by extending the PIM protocol. Node 2 uses its own BIER information to form a BIER advertisement message, and encapsulates the BIER advertisement packet based on the BIER MPLS encapsulation subtype shown in FIG. 4, and then sends it to the

adjacent node

1, 3, 5; After receiving the information sent by the

node

2, 3, 5 obtains the BIER information of the node 2 after parsing; the neighboring

nodes

1, 3, 5 continue to transmit the BIER information of the node 2 by the same processing method as that of the node 2. Other nodes in the network until all nodes receive the BIER information of node 2.

In this process, some nodes may not support BIER forwarding capability, so the BIER information of node 2 will not be forwarded to the node that does not support BIER forwarding capability. For example, capability negotiation can be performed before the neighbor is established by the PIM protocol, so that the BIER information is not forwarded to the node that does not support the BIER forwarding capability. For example, whether the neighboring node determines whether the node supports the BIER forwarding capability by whether the value of the BIER option in the PIM hello message is 4.

Similarly, the BIER information of other nodes can also be transmitted by means of PIM protocol extension, that is, the BIER information is transmitted by the same processing method as that of the above described node 2, so that all nodes in the network supporting BIER forwarding capability Can receive BIER information of other nodes.

Then, each node performs route calculation according to the received BIER information; for example, directly searches for a local unicast routing table according to the BFR-Prefix information (the IP address of the BIER edge node) in the BIER information (a single unicast protocol list) Broadcast routing table), obtain the corresponding next hop to form a BIER forwarding routing table.

Each node forwards the received packet based on the BIER technology according to the BIER forwarding routing table.

In the above process, neighboring nodes are kept alive by the BIER option in the PIM hello message.

Example three

Here, in the second example, the BIER information is transmitted by each node participating in the BIER information flooding. In this example, the candidate manager mechanism of the PIM protocol is used to complete the delivery of the BIER information.

First, add a PIM packet type-BIER advertisement packet.

The structure of the BIER advertisement message is shown in Figure 4. The specific meaning of each field has been described above and will not be described here.

Second, add the BIER MPLS encapsulation subtype

The structure of the BIER MPLS encapsulation subtype is shown in Figure 5. The specific meaning of each field has been described above and will not be described here.

Third, add PIM hello message BIER option

The fields of the newly added BIER Hello option are shown in Figure 6. The specific meaning of each field has been described above and will not be described here.

Fourth, add a PIM packet type-BIER management packet.

In the field of the BIER management message shown in Figure 7:

The PIM version (PIM Ver), reserved field (Reserved), checksum (Checksum) description is consistent with the definition in RFC4601;

BIER-M Priority: The BIER Manager is elected by priority. In this example, the default priority is 64, the maximum is 255, and the minimum is 0. The greater the priority, the higher the priority;

Frag BIER Num M: the number of BIER information in this fragment;

BIER-M Address: The address of the BIER manager, Encoded-Unicast format, and the length is different according to IPv4 and IPv6. For details, see the relevant section of RFC4601.

N flag: When the N flag is set, the receiver cannot forward this message.

Type: The embodiment of the present disclosure is not limited, and may be any one of the currently undefined PIM message option types;

Fragment Tag: When the BIER management packet is subcontracted, the representation is the same message;

The meanings of the other fields are the same as those of the fields of the BIER advertisement message shown in FIG. 3, and are not repeated here.

First, the candidate BIER manager discovery process is performed.

For example, a node that supports BIER forwarding capability configures itself as a manager as a candidate manager and passes the BIER management message shown in Figure 7 (based on the BIER MPLS encapsulation subtype encapsulation shown in Figure 5). Flooding into the network has caused other nodes to know themselves as candidate managers.

Among them, FIG. 8 shows the transmission direction of the message during the candidate BIER manager discovery process. As shown in Figure 8, when the packet is flooded, the destination address is -224.0.0.13 (IPv4) or FF02::0D (IPv6). The receiving node performs path check (Reverse Path Forwarding (RPF) check to avoid ring formation) according to the unicast route to the BIER-M Address, thereby directly receiving the packet from the unicast next hop neighbor. . The node that received this message continues flooding to all neighbors (adjacent nodes).

In the flooding process, if a new neighbor is accessed, the receiving node immediately sends the packet to the new neighbor. The destination address of the packet is the unicast address of the neighbor, and the N flag is set. This type of message is not checked by RPF.

In addition, for devices that do not support this type of message, it should be transparently flooded. That is, the message can be directly transmitted.

The receiving node receives the packet of the new BIER-M address, and the node of the address is the candidate BIER manager.

As can be seen from the above description, the node with the candidate manager qualification carries its own BIER management information when sending PIM protocol packets (BIER management packets).

Each candidate manager in the network uses the above process to let all nodes in the network that support the BIER forwarding capability know itself as a candidate manager.

Next, proceed to the BIER Manager election process.

Through the above process, each node supporting the BIER forwarding capability can learn all the candidate BIER managers in the network, and then perform election according to the priority carried by the BIER management messages sent by each candidate BIER manager, in these candidate BIERs. In the manager, the candidate BIER manager with the highest priority is elected as the target BIER manager. When there are at least two candidate BIER managers with the highest priority, the candidate is elected according to the IP address of the BIER manager, and the candidate with the large IP address is selected. The BIER Manager is elected as the target BIER Manager.

That is to say, when the target BIER manager is elected, the election is first performed according to the priority carried in the message. If the priority is different, the highest priority is elected as the target BIER manager; if the priority is the same, the election is further based on the IP address size, and the address is elected as the target BIER manager.

Third, BIER information notice

After determining the target BIER manager, the other nodes use their own BIER information to form a BIER advertisement message, and encapsulate the BIER advertisement message based on the BIER MPLS encapsulation subtype shown in FIG. 5, and then send it to the target BIER manager. As shown in Figure 9.

Among them, this message is a unicast message. The hold time can be set to 210s, and the advertisement message can be periodically advertised in 60s.

Fourth, flooding BIER information

After receiving the BIER advertisement message of each node, the target BIER manager forms a BIER management message (based on the BIER MPLS encapsulation subtype encapsulation shown in FIG. 5) as shown in FIG. 7 together with the locally configured BIER information. It is flooded periodically. The flooding period can be 60s by default. The hold time is the keepalive time carried in the received BIER advertisement. If one packet cannot be filled, packetization is performed, and the Fragment Tag field of the packet is the same.

Fifth, generate a BIER forwarding routing table

Each node performs route calculation based on the received BIER information; for example, directly searches for a local unicast routing table (any unicast routing unicast routing) according to the BFR-Prefix information (the IP address of the BIER edge node) in the BIER information. Table), obtain the corresponding next hop to form a BIER forwarding routing table.

As can be seen from the above description, in this example, the target BIER manager is generated first, and the target BIER manager collects all the node BIER information, collects them, and sends them to all nodes supporting the BIER forwarding capability, thereby making each The node can obtain the BIER information of other nodes and use it for path calculation to form a BIER forwarding table.

In the above process, when a node supporting the BIER forwarding capability is to be logged out, the node informs the target BIER manager through the newly added BIER notification message as shown in FIG. 4, wherein the hold time is set to 0, indicating that Undo this BIER message.

After receiving the packet, the target BIER manager floods through the BIER management packet shown in FIG. 7. For example, setting the hold time of the BIER management message to 0 indicates that the BIER information is to be revoked.

Example four

In the PIM protocol extension mode, you need to add a PIM packet type, a new BIER information subtype, a new BIER MPLS encapsulation subtype, and a new BIER Hello option. Specifically include:

First, add a PIM packet type-BIER advertisement packet.

FIG. 10 is a schematic structural diagram of a newly added BIER advertisement message; as shown in FIG. 10, in the field of the newly added BIER advertisement message:

Sub Type Num: A packet can carry multiple subtypes. This field is the number of subtypes carried, and the length is 1 byte.

Holdtime: The time when the information is to be saved, the embodiment of the present disclosure may default to 210s, and the length is 1 byte;

Sub Type: Defined for subtypes related to BIER, extensible, 1 byte in length;

Length: Length is long (that is, the content is changed), the length of the subtype value, and the length is 1 byte.

Second, add a BIER message subtype

Figure 11 is a schematic diagram showing the structure of a new BIER information subtype. As shown in Figure 11, in the field of the new BIER information subtype:

Sub Type: The specific embodiment of the present disclosure does not require specific requirements, and is 1 in the example;

Reserved field (Reserved1): 0 by default;

Subdomain-id: A unique value that represents the subdomain of the BIER. 1 byte in length;

BFR number (BFR-id): 2 bytes in length, if there is no BFR-id, it is set to an illegal value;

As can be seen from the above description, the BIER information subtype (BIER information sub-attribute) described in FIG. 11 is an attribute that the BIER advertisement message shown in FIG. 4 must carry, that is, in this example, FIG. 10 and The sum of the information shown in Fig. 11 corresponds to the BIER notification message shown in Fig. 4.

Third, add the BIER MPLS encapsulation subtype

The specific structure is shown in Figure 5. The fields in the BIER MPLS encapsulation subtype have been detailed in the second example and will not be described here.

Taking node 2 as an example, the BIER information of node 2, including: BFR-prefix information, sub-domain-id information, BSL information, etc., can be implemented by extending the PIM protocol. The node 2 uses its own BIER information to form the BIER advertisement message shown in FIG. 10, and forms the BIER information subtype shown in FIG. 11, and based on the BIER MPLS encapsulation subtype shown in FIG. 5, the BIER advertisement message and the BIER. The information subtype is encapsulated and then sent to the neighboring

nodes

1, 3, 5; the neighboring

nodes

1, 3, 5 receive the information sent by the node 2, and after parsing, the BIER information of the node 2 is obtained; the neighboring

node

1, 3, 5, using the same processing method as node 2, the BIER information of node 2 is continuously transmitted to other nodes in the network until all nodes receive the BIER information of node 2.

As can be seen from the above description, in the present example, only the message shown in FIG. 4 is divided into the message shown in FIG. 10 and the BIER information subtype shown in FIG. 11, and the other processing methods and the process of the second example. It's exactly the same. Therefore, the message format in this example is also applicable to the scheme described in Example 3. The difference from the third example is that the message shown in FIG. 4 is divided into the message shown in FIG. 10 and the message shown in FIG. BIER information subtype.

Example five

Based on the first example, this example describes in detail the process of transmitting BIER information based on TCP.

In this example, the mechanism of TCP transmission is used to implement the transmission of BIER information. The process includes the following steps:

First, the nodes in the network specify the BIER Manager by static configuration.

Here, the configured manager address should be consistent in the BIER domain.

Next, the node (BIER device) that supports the BIER forwarding capability passes the BIER information to the BIER manager through the unicast message.

Here, in this example, the message is a TCP BIER advertisement message.

Then, after receiving the BIER information transmitted by the BIER device, the BIER manager periodically floods the surrounding devices with the broadcast or protocol multicast destination address.

The node that supports the BIER forwarding capability receives the packet from the BIER manager and uses the IP address of the BIER manager to find the unicast routing table to find the next hop and the outbound interface. Only the source IP address and inbound interface of the received packet are received. It is received only after the next hop and the outbound interface of the unicast routing table are met, otherwise it is discarded.

Wherein, when the BIER device revokes the BIER information, it sends a TCP BIER advertisement message that does not contain the BIER information to the BIER manager.

In addition, when the BIER Manager discovers a TCP break with the BIER device, the BIER information received from the BIER device should be aged.

The nodes in the network specify the manager through the static configuration mode. When the BIER device interacts with the manager, the BIER device uses the TCP link advertisement mode. This mode can make the message delivery more reliable. After the BIER information transmission is completed, each BIER device performs a unicast routing table search according to the received BIER information of other BIER devices, and forms a BIER forwarding routing table.

Example six

To implement the method of the embodiments of the present disclosure, the present example provides a processing device based on BIER information. As shown in FIG. 12, the device includes:

The first generating unit 121 is configured to generate a message by using the BIER information based on the first protocol mechanism;

The sending unit 122 is configured to send the generated message; wherein,

The first generating unit 121 is configured to implement one of the following:

In addition, in actual application, when the device is located on the BIER device manager, the device may further include:

The receiving unit is set to obtain BIER information.

Those skilled in the art should understand that the implementation functions of the units of the apparatus shown in FIG. 12 can be understood by referring to the related description of the foregoing protocol-independent processing method of BIER information.

In practical applications, the first generating unit 121 may be implemented by a processor in a BIER information-based processing device; the transmitting unit 122 and the receiving unit may be implemented by a communication interface of a BIER information-based processing device.

To implement the method of the embodiment of the present disclosure, the present example further provides a processing device based on BIER information. As shown in FIG. 13, the device includes:

The receiving and parsing unit 131 is configured to receive a packet; the received packet is transmitted according to a first protocol mechanism; and parsing the packet to obtain BIER information;

The second generating unit 132 is configured to generate a BIER forwarding routing table based on the obtained BIER information and in combination with the unicast routing table;

The receiving and parsing unit 132 is configured to implement one of the following:

When the device is located at the intermediate node of the BIER information transmission, the received BIER information is flooded to the adjacent node, or the BIER device manager is required to send its own BIER information, so the device can also be used in actual application. include:

The sending unit is set to send BIER information.

Those skilled in the art should understand that the implementation functions of the units of the apparatus shown in FIG. 13 can be understood by referring to the related description of the foregoing protocol-independent processing method of BIER information.

In practical applications, the receiving and parsing unit 131 may be implemented by a processor in a BIER-based processing device in conjunction with a communication interface; the transmitting unit 132 may be implemented by a communication interface of a BIER-based processing device.

Those of ordinary skill in the art will appreciate that all or some of the steps, systems, and functional blocks/units of the methods disclosed above may be implemented as software, firmware, hardware, and suitable combinations thereof. In a hardware implementation, the division between functional modules/units mentioned in the above description does not necessarily correspond to the division of physical components; for example, one physical component may have multiple functions, or one function or step may be composed of several physical The components work together. Some or all of the components may be implemented as software executed by a processor, such as a digital signal processor or microprocessor, or as hardware, or as an integrated circuit, such as an application specific integrated circuit. Such software may be distributed on a computer readable medium, which may include computer storage media (or non-transitory media) and communication media (or transitory media). As is well known to those of ordinary skill in the art, the term computer storage medium includes volatile and nonvolatile, implemented in any method or technology for storing information, such as computer readable instructions, data structures, program modules or other data. Sex, removable and non-removable media. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cartridge, magnetic tape, magnetic disk storage or other magnetic storage device, or may Any other medium used to store the desired information and that can be accessed by the computer. Moreover, it is well known to those skilled in the art that communication media typically includes computer readable instructions, data structures, program modules, or other data in a modulated data signal, such as a carrier wave or other transport mechanism, and can include any information delivery media. .

The above description is only for the exemplary embodiments of the present disclosure, and is not intended to limit the scope of the disclosure.

Industrial applicability

The method and device for processing BIER information related to the protocol provided by the embodiment of the present disclosure generates a message by using the BIER information based on the first protocol mechanism; sends the generated message; receives the message; and receives the received message based on the first The protocol mechanism performs the transmission; parses the message to obtain the BIER information; and generates a BIER forwarding routing table based on the obtained BIER information and the unicast routing table; wherein the first protocol mechanism is used for transmitting the BIER information, and A protocol mechanism that is independent of the unicast protocol, that is, the BIER information is transmitted through a protocol mechanism independent of the unicast protocol. When performing BIER topology calculation, any unicast routing table can be used instead of relying on some unicast protocol. That is, there is no requirement for unicast, so that it can get rid of the BIER technology's dependence on the specific unicast protocol, and it does not need unicast to support the BIER function for the BIER extension. Therefore, it is easy to promote the BIER technology.

Claims

A method for explicitly copying BIER information from a protocol-independent bit index, comprising:

Generating a message using the BIER information based on the first protocol mechanism (101);

Sending the generated message (102); wherein

The BIER information is used to generate a BIER forwarding routing table; the BIER forwarding routing table is a forwarding routing table generated by using the BIER information and combined with a unicast routing table; the first protocol mechanism is used for transmitting BIER information, and A protocol mechanism that is independent of the unicast protocol.
The method of claim 1, wherein the generating the message (101) using the BIER information based on the first protocol mechanism comprises one of the following:

The first packet is generated by using the BIER information based on the extended protocol-independent multicast PIM protocol mechanism;

Generating a second packet by using the BIER information based on the Internet Protocol IP mechanism; when the source IP address and the inbound port IP number of the second packet meet the next hop and the outbound port IP number of the unicast routing table, The second message is received;

The third data packet is generated by using the BIER information according to the UDP mechanism of the user datagram protocol. When the source IP address and the inbound port UDP number of the third packet match the next hop and the outbound port UDP number of the unicast routing table, The third message is received;

The fourth packet is generated by using the BIER information according to the TCP mechanism of the transmission control protocol; when the source IP address of the fourth packet, the TCP number of the ingress port, and the next hop of the unicast routing table and the TCP number of the egress port are met, The fourth message is received.
The method of claim 2, wherein the generating the first message by using the BIER information based on the extended PIM protocol mechanism comprises:

Generating a first BIER advertisement message based on the PIM protocol by using the BIER information; the first BIER advertisement message includes information for implementing packet forwarding encapsulated in the BIER format; the first BIER advertisement message is used to notify the corresponding BIER information for BIER equipment.
The method of claim 2, wherein the generating the first message by using the BIER information based on the extended PIM protocol mechanism comprises:

Generating a first BIER management message based on the PIM protocol by using the BIER information; the first BIER management message includes information for implementing packet forwarding encapsulated in the BIER format; the first BIER advertisement message is used to notify the network BIER information for all BIER devices.
The method of claim 4, wherein before the generating of the BIER management message, the method further comprises:

Generating a second BIER management message based on the PIM protocol;

Sending the second BIER management message; the second BIER management message is used to elect a BIER device manager in the network.
The method of claim 2, wherein the generating the first message by using the BIER information based on the extended PIM protocol mechanism comprises:

Using the BIER information, generating a second BIER advertisement message based on the PIM protocol, and generating a type, length, and value TLV of the second BIER advertisement message; the second BIER advertisement message includes a packet for implementing BIER format encapsulation Forwarded information; the second BIER advertisement message and the TLV are used to notify the BIER information of the corresponding BIER device;

Correspondingly, the second BIER advertisement message and the TLV are sent.
The method according to any one of claims 3 to 6, wherein the method further comprises:

Generate a PIM hello packet based on the PIM protocol.

The PIM hello message is sent; the PIM hello message is used to notify the BIER capability of the BIER device.
The method according to claim 2, wherein the second message includes information for implementing packet forwarding of the BIER format encapsulation; and the second message is used for advertising BIER information of all BIER devices in the network.
The method according to claim 2, wherein the third message includes information for implementing packet forwarding of the BIER format encapsulation; and the third message is used for advertising BIER information of all BIER devices in the network.
The method according to claim 2, wherein the fourth message includes information for implementing packet forwarding of the BIER format encapsulation; and the fourth message is used for advertising BIER information of all BIER devices in the network.
The method according to any one of claims 8 to 10, wherein, when the second message, the third message or the fourth message is sent, the message is sent in one of the following manners:

Sending packets in unicast mode;

Sends packets in broadcast or multicast mode.
A protocol-independent processing method for BIER information, including:

Receiving a message (201), wherein the received message is transmitted according to a first protocol mechanism;

Parsing the message to obtain BIER information (202);

Generating a BIER forwarding routing table (203) based on the obtained BIER information and in combination with the unicast routing table;

The first protocol mechanism is a protocol mechanism for transmitting BIER information and independent of the unicast protocol.
The method according to claim 12, wherein the receiving message (201), the received message is transmitted based on a first protocol mechanism; parsing the message to obtain BIER information (202), including one of the following:

Receiving the first packet; parsing the first packet according to the extended PIM protocol mechanism to obtain BIER information;

Receiving the second packet when the source IP address and the inbound port IP address of the second packet match the next hop and the outbound port IP number of the unicast routing table; and parsing the second packet based on the IP mechanism , get BIER information;

The third packet is received when the source IP address and the inbound port UDP number of the third packet match the next hop and the outbound UDP number of the unicast routing table. The third packet is parsed based on the UDP mechanism. , get BIER information;

Receiving the fourth packet when the source IP address and the ingress port TCP number of the fourth packet match the next hop and the outbound TCP number of the unicast routing table; and parsing the third packet based on the TCP mechanism , get BIER information.
The method according to claim 13, wherein the first message is a first BIER advertisement message;

Correspondingly, the first BIER advertisement message is parsed to obtain information for implementing packet forwarding of the BIER format encapsulation; and the first BIER advertisement message is used to notify the BIER information of the corresponding BIER device.
The method according to claim 13, wherein the first message is a first BIER management message;

Correspondingly, the first BIER management packet is parsed to obtain information for implementing packet forwarding of the BIER format encapsulation; and the first BIER advertisement packet is used to notify BIER information of all BIER devices in the network.
The method of claim 15, wherein before the receiving the first BIER management message, the method further comprises:

Receiving a second BIER management message;

Parsing the second BIER management message based on the PIM protocol to obtain candidate BIER manager related information;

The BIER device manager in the network is elected using the candidate BIER manager related information.
The method according to claim 13, wherein the first message is a second BIER advertisement message;

When the second BIER advertisement message is received, the method further includes:

Receiving a TLV of the second BIER notification message;

The TLV and the BIER advertisement message are parsed, and the information for forwarding the packet in the BIER format encapsulation is obtained. The second BIER advertisement message and the TLV are used to notify the BIER information of the corresponding BIER device.
The method of any of claims 14 to 17, wherein the method further comprises:

Receive a PIM hello message;

By analyzing the PIM hello message based on the PIM protocol, the BIER capability of the BIER device is known.
The method according to claim 13, wherein the second packet is parsed to obtain information for implementing packet forwarding of the BIER format encapsulation; and the second packet is used for advertising BIER information of all BIER devices in the network. .
The method according to claim 13, wherein the third packet is parsed to obtain information for implementing packet forwarding of the BIER format encapsulation; and the third packet is used for advertising BIER information of all BIER devices in the network. .
The method according to claim 13, wherein the fourth packet is parsed to obtain information for implementing packet forwarding of the BIER format encapsulation; and the fourth packet is used for advertising BIER information of all BIER devices in the network. .
A processing device based on BIER information, comprising:

The first generating unit (121) is configured to generate a message by using the BIER information based on the first protocol mechanism;

a sending unit (122) configured to send the generated message; wherein

The BIER information is used to generate a BIER forwarding routing table; the BIER forwarding routing table is a forwarding routing table generated by using the BIER information and combined with a unicast routing table; the first protocol mechanism is used for transmitting BIER information, and A protocol mechanism that is independent of the unicast protocol.
The apparatus according to claim 22, wherein said first generating unit (121) is arranged to implement one of the following:

Generating the first packet by using the BIER information based on the extended PIM protocol mechanism;

Generating a second packet by using the BIER information based on the IP mechanism; when the source IP address and the ingress port IP number of the second packet meet the next hop and the outbound port IP number of the unicast routing table, the second The message is received;

The third packet is generated by using the BIER information based on the UDP mechanism; when the source IP address of the third packet, the UDP number of the ingress port, and the next hop of the unicast routing table, the UDP number of the outbound port, the third The message is received;

The fourth packet is generated by using the BIER information according to the TCP mechanism. When the source IP address of the fourth packet, the TCP number of the ingress port, and the next hop of the unicast routing table, and the outgoing port TCP number, the fourth packet is used. The message was received.
A processing device based on BIER information, comprising:

a receiving and parsing unit (131) configured to receive a message; the received message is transmitted according to a first protocol mechanism; and parsing the message to obtain BIER information;

a second generating unit (132) configured to generate a BIER forwarding routing table based on the obtained BIER information and in combination with the unicast routing table;

The first protocol mechanism is a protocol mechanism for transmitting BIER information and independent of the unicast protocol.
Apparatus according to claim 24, wherein said receiving and parsing unit (131) is arranged to implement one of the following:

Receiving the first packet; parsing the first packet according to the extended PIM protocol mechanism to obtain BIER information;

Receiving the second packet when the source IP address and the inbound port IP address of the second packet match the next hop and the outbound port IP number of the unicast routing table; and parsing the second packet based on the IP mechanism , get BIER information;

The third packet is received when the source IP address and the inbound port UDP number of the third packet match the next hop and the outbound UDP number of the unicast routing table. The third packet is parsed based on the UDP mechanism. , get BIER information;

Receiving the fourth packet when the source IP address and the ingress port TCP number of the fourth packet match the next hop and the outbound TCP number of the unicast routing table; and parsing the third packet based on the TCP mechanism , get BIER information.