WO2015184771A1 - Method and node device for operation, administration, and maintenance of service function chaining - Google Patents

Abstract

A method and node device for operation, administration, and maintenance (OAM) of service function chaining. The method comprises: when a source service node is performing an OAM operation for alias information, the source service node determines either an SFC or a service function path that is bound with the alias information; and, the source service node performs an OAM operation on the determined SFC or service function path, generates a corresponding OAM packet and transmits same to a destination service node of the OAM operation.

Description

Business function chain operation, management and maintenance method and node device Technical field

The present invention relates to the field of Internet devices, and in particular, to a method, a node device for implementing a service chain management, management and maintenance (OAM).

Background technique

SFC (Service Function Chaining) is a network technology currently being researched and standardized. Since the development of the data center network to the Overlay network, the network edge has become the demarcation point between the virtual network and the physical network, where the network edge is Server or ToR, and possibly Gateway. However, Overlay technology does not solve all the problems. There are many Middleware in the data center, such as firewall/load balancer. These devices are processed based on user services. If you traverse these devices through tunnels, it is obviously not feasible.

This deployment model of the data center requires that the virtual firewall/load balancer can be deployed arbitrarily in the network, that is, independent of the network topology. The new question is how to handle traffic through the virtual firewall/load balancer. Therefore, new middleware such as virtual firewall/load balancer is generated. These virtual firewall/load balancer and other business processing functions are independent of the original network topology and are implemented by standard servers.

We call the service processing function such as virtual firewall/load balancer/gateway as Service Function, and the traffic is processed through a series of Service Function to form Service Function Chaining, which is the business function chain. The business function chain is an orderly arrangement of some abstract business functions. The SFCs are not defined in the order of which SFFs or/and SFs are ordered when the specific service traffic is forwarded. As shown in Figure 1, it represents two Service Function Chainings, sometimes called the Service Chain Service Chain.

The framework of SFC can be basically divided into the following components:

1. Service Overlay, that is, Overlay technology that each service function node needs to communicate;

2. Generic Service Control Plane (GSCP, the general service control plane) is the controller that forms the Service Function Chaining;

3. Service Classifier, which requires the identification of the stream, and then the specific stream, for a specific Service Function Chaining;

4. SF (Service Function), a component that performs business processing on data packets;

5. Service Function Forwarder (SFF), which is responsible for forwarding between multiple internal SFs of the same service node. After the data packet of the overlay is encapsulated and decapsulated by the network forwarding device of the service node, the data packet is encapsulated, decapsulated, and updated by the NSF (Network Service Header). The format of the service function packet header packet is as shown in FIG. 2 .

6. NF (Network Forwarder), which is responsible for forwarding between multiple SFFs of the same service node; and encapsulating and decapsulating the Overlay layer of the Overlay data packet; and simultaneously processing between different service nodes Forward

SFP (service function path), as shown in Figure 3, the SFP starts from the classifier and goes through a number of ordered specific service function instances to reach a service processing path of the destination. In some cases, the general service control platform GSCP does not know all the service function instances that pass through the path, such as the load sharing scenario or the service service level scenario. At this time, the abstract service function chain SFC and the real specific traffic forwarding are passed. A description of such a business function chain between paths formed by an ordered business instance, also referred to as a business function path. A service function chain may include multiple service function paths, and different service function paths correspond to different policies.

8.Dataplane Metadata (control plane metadata), which is a major feature, Metadata (metadata) allows each business function node to exchange information with each other to achieve certain business processing purposes.

To sum up, SFC is a kind of separation of network device service functions and forwarding, thus achieving independent operation and processing of service functions, and improving the forwarding performance of network devices.

Operation, Management, and Maintenance (OAM) technology is a network transmission protocol for network connectivity detection, fault location, and troubleshooting, and provides a trigger mechanism for protection switching when a failure occurs. It includes the link connectivity detection CV (Connectivity Verification) mechanism, the Ping mechanism to And the Trace mechanism. For different bearer network protocols, there is a corresponding OAM mechanism. For example, Ethernet has an Ethernet OAM protocol, an IP network has an IP OAM protocol, and an MPLS network has an MPLS OAM.

In the SFC related technology, the implementation details of the SFC OAM technology are being discussed. The SFC OAM technology proposed by Cisco has the core idea of preserving a field in the service function packet header NSH to identify the OAM packet and the OAM packet type. As shown in FIG. 4, the IETF also proposes to reserve a bit in the service function packet header NSH for identifying the OAM packet, and which type of OAM packet is placed in the service function packet header NSH. In the other messages, as shown in Figure 5. However, regardless of the solution, there is a problem that the actual operator does not necessarily know the address of the last hop of the service function chain, that is, when SFC Ping or SFC Trace is to be performed, the destination address is not known. How much should be filled. Even if it can be obtained in other ways, it is not a very simple and quick method for the operator.

Summary of the invention

The embodiments of the present invention provide a service function chain (SFC) operation, management, and maintenance (OAM) method and a node device to solve the problem that an operator cannot implement various SFC OAMs simply and quickly.

A business function chain (SFC) operation, management, and maintenance (OAM) method, including:

When the source service node performs an OAM operation on the alias information, the source service node determines an SFC or a service function path that is bound to the alias information.

The source service node performs an OAM operation on the determined SFC or the service function path, and generates a corresponding OAM message and sends the message to the destination service node of the OAM operation.

Optionally, the method further includes: configuring, by the source service node, the alias information of the SFC or the service function path in the SFC domain, and the binding relationship between the SFC or the service function path corresponding to the alias information; or

The source service node receives, from the universal service platform controller, the alias information of the SFC or the service function path in the SFC domain, and the binding relationship between the SFC or the service function path corresponding to the alias information;

The alias information of the SFC or service function path is unique within the SFC domain.

Optionally, in the foregoing method, the source service node generates a corresponding OAM packet and sends the corresponding OAM packet. The destination service node includes:

The source service node parses the OAM operation, and obtains the number M of service nodes that the OAM packet corresponding to the OAM operation needs to go through, and the determined SFC or the service function path after the source service node M service nodes are determined as destination service nodes, and M is a positive integer;

The source service node sends the generated OAM message to the destination service node through the service node on the determined SFC or service function path.

Optionally, in the foregoing method, when the number M of service nodes that the OAM packet needs to go exceeds the number of remaining service nodes after starting the source service node on the determined SFC or service function path, The source end node device determines the last service node on the determined SFC or service function path as the destination service node.

Optionally, in the foregoing method, the source service node is a service classifier, or is any one of the service nodes in the SFC or service function path.

The embodiment of the invention further discloses a service node device, including:

a first unit, configured to: when the service node device performs an operation, management, and maintenance (OAM) operation on the alias information, determine a service function chain (SFC) or a service function path that is bound to the alias information; as well as

And a second unit, configured to: perform an OAM operation on the SFC or the service function path determined by the first unit, generate a corresponding OAM message, and send the message to the destination service node of the OAM operation.

Optionally, the foregoing apparatus further includes:

a third unit, configured to: configure an alias information for the SFC or the service function path in the SFC domain, and a binding relationship between the SFC or the service function path corresponding to the alias information; or

Receiving and storing, from the general service platform controller, the alias information of the SFC or the service function path in the SFC domain, and the binding relationship between the SFC or the service function path corresponding to the alias information;

The alias information of each SFC or service function path is unique within the SFC domain.

Optionally, in the foregoing device, the second unit includes:

a parsing module, configured to: parse the OAM operation, obtain the number M of service nodes that the OAM packet corresponding to the OAM operation needs to go, and determine the SFC or the service function path after the source service node The Mth service node is determined to be the destination service node, and M is positive. Integer; and

And a sending module, configured to: send the generated OAM message from the source service node to the destination service node by using the determined service node on the SFC or the service function path.

Optionally, in the foregoing device, the parsing module is further configured to: the number M of service nodes that the OAM packet needs to go exceeds the determined SFC or the service function path after starting from the source service node. When the number of remaining service nodes is the number, the parsing module determines the last service node on the determined SFC or service function path as the destination service node.

Optionally, the service node device is any one of the service node devices on the SFC or the service function path.

The embodiment of the invention also provides a computer program for implementing the above method.

Embodiments of the present invention also provide a carrier for storing the computer program.

With the technical solution of the embodiment of the present application, the operator can easily and quickly obtain the link information of the service chain, and diagnose and locate the link information of the service chain, thereby implementing various SFC OAMs simply and quickly.

BRIEF abstract

Figure 1 is an example diagram of an SFC (Business Function Chain);

2 is a schematic diagram of a format of a service function packet header;

Figure 3 is a diagram showing an example of an SFP (service function path);

4 is a schematic diagram of a format of an SFC OAM packet;

Figure 5 is a schematic diagram of the second format of the SFC OAM packet;

6 is a schematic diagram of an SFC Ping function initiated by a head node in an embodiment of the present invention;

7 is a schematic diagram of an SFC Ping function based on a hop limit in a head node according to an embodiment of the present invention;

FIG. 8 is a schematic diagram of an SFC Trace function initiated by an intermediate node according to an embodiment of the present invention;

FIG. 9 is a schematic diagram of an SFC Trace function initiated by an intermediate node with a hop limit according to an embodiment of the present invention; Schematic diagram

FIG. 10 is a schematic structural diagram of a node device according to an embodiment of the present invention.

Preferred embodiment of the invention

The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that, in the case of no conflict, the features in the embodiments and the embodiments of the present application may be combined with each other arbitrarily.

Example 1

This embodiment provides an OAM method for an SFC, including the following operations:

When the source service node performs an OAM operation on the alias information, the source service node determines an SFC or a service function path that is bound to the alias information.

The source node device performs an SFC OAM operation on the determined SFC or the service function path, and generates a corresponding OAM packet and sends it to the destination service node of the OAM operation.

The SFC OAM in this embodiment may include an SFC ping function, or an SFC Trace function, or an SFC BFD function, or an SFC connectivity detection function, and the implementation mechanism may follow the relevant specifications of the SFC OAM. The node device involved in this embodiment may be a service classifier, or any one of a service function chain or a service function path.

Optionally, the foregoing method may further include: separately setting unique alias information for the SFC or the service function path in the SFC domain, and binding the configured path information with the information of the corresponding SFC or the service function path. The information of the SFC or the service function path includes specific information and lower layer information of the service function chain or the service function path.

The alias information, and the binding relationship between the alias information and the corresponding SFC or the service function path may be uniformly sent to the service node by the general service platform controller, or may be statically configured locally at the service node.

It should be noted that the process in which the source service node generates the corresponding OAM packet and sends it to the destination service node may include the following operations:

The source service node first parses the OAM operation, and obtains the number M of service nodes that the OAM packet corresponding to the OAM operation needs to go through, and determines the SFC or the service function path on the source end. The Mth service node after the service node is determined as the destination service node, and M is a positive integer;

Then, the generated OAM packet is sent from the source service node to the destination service node through the determined SFC or the service node on the service function path.

The number of service nodes that the OAM packet needs to go through exceeds the number of remaining service nodes after starting the source service node on the determined SFC or service function path, and the source node device may determine the SFC or The last service node on the service function path is determined as the destination service node.

In addition, when the source service node parses the OAM operation, it can parse the OAM packet type and other information in addition to the number of service nodes that the OAM packet needs to be obtained, so that when the OAM packet is generated, The parsed information can be encapsulated in an OAM message. Specifically, the operation of encapsulating the parsed information into the OAM packet may refer to the existing OAM packet encapsulation operation, and details are not described herein.

The detailed implementation process of the above method will be described below with reference to the accompanying drawings and specific applications.

As shown in FIG. 6, the specific service function chain based on the SFC ping function initiated by the head node as the source service node includes: SF1--->SF2--->SF3;

Defining an alias for the business function chain: SFP-Mike; and associating the alias with the business function chain;

When the operator initiates the SFC ping function for the service function chain, it is no longer necessary to know the IP address of the last hop service function, but only the operation is as follows:

Ping SFC SFC-Mike.

It should be noted that, in this scenario, after the source service node SF1 resolves the OAM operation, the number of service nodes that the packet needs to go through may not be obtained. In this case, the OAM operation is performed on the entire service function chain by default. The last service node SF3 of the chain acts as the destination service node.

As shown in Figure 7, the SFC Ping-based service is initiated by the head node as the source service node with the hop limit (that is, the number of service nodes that the OAM packet needs to go through is less than the number of service nodes in the entire service function chain). The functional chain includes: SF2--->SF3--->SF4;

Defining an alias for the business function chain: SFPID100; and associating the alias with the business function chain;

When the operator initiates the SFP Ping function with the hop limit of 2 for the service function chain (that is, the number of service nodes M to be experienced by the OAM packet is 2), it is no longer necessary to know the IP address of the second hop service function. And only need to operate as follows:

Ping SFC SFCID100maximum_hops 2.

As shown in Figure 8, the complete path of the service function chain includes: SF3--->SF4--->SF5;

Define an alias: Broadband1; associate the alias with the business function chain;

When the intermediate node service function 3 is used as the SFCTrace function initiated by the source service node of the OAM operation, it is no longer necessary to know the IP address of the last hop service function, but only needs to operate on the service node 3 as follows:

Trace SFC Broadband1.

It should be noted that, in this scenario, after the source service node SF3 resolves the OAM operation, the number of service nodes that the packet needs to go through may not be obtained. In this case, the default is the remaining service function chain after starting from the source service node. The OAM operation is performed, that is, the last service node SF5 of the service function chain is used as the destination service node.

As shown in Figure 9, the complete path of the service function chain includes: SF4--->SF5--->SF6;

Define an alias: Data Center 1 (Datacenter1);

When the intermediate node service function 4 is used as the SFC Trace function of the source service node to initiate the hop count to 1 (that is, the number of service nodes M to be experienced by the OAM packet is 1), the IP of the second hop service function is no longer needed. What is the address, and only need to operate on business node 4 as follows:

Trace SFC Datacenter1maximum_hops 1.

Example 2

As shown in FIG. 10, this embodiment provides a node device, which can implement the foregoing method, and at least includes the following units.

The first unit determines a service function chain (SFC) or a service function path bound to the alias information when the device performs an operation, management, and maintenance (OAM) operation on the alias information;

The second unit performs an OAM operation on the SFC or the service function path determined by the first unit, generates a corresponding OAM message, and sends the corresponding OAM message to the destination service node of the OAM operation.

Optionally, the device may further include: a third unit, configured to configure alias information for the SFC or the service function path in the SFC domain, and a binding relationship between the alias information and the corresponding SFC or the service function path; or from the general service platform controller Receiving and storing the alias information of the SFC or the service function path in the SFC domain, and the binding relationship between the alias information and the corresponding SFC or service function path; wherein the alias information of each SFC or service function path is unique within the SFC domain.

The second unit may be further divided into a parsing module and a sending module.

Parsing the module, parsing the OAM operation, obtaining the number M of service nodes that the OAM message corresponding to the OAM operation needs to pass, and determining the Mth service node after the source service node on the determined SFC or service function path as the destination End service node;

The parsing module may determine the determined SFC or service function when the number of service nodes that the OAM packet needs to go exceeds the number of remaining service nodes after starting the source service node on the determined SFC or service function path. The last service node on the path is determined to be the destination service node.

The sending module sends the generated OAM message from the source service node to the destination service node through the determined SFC or the service node on the service function path. It should be noted that the foregoing device may be a service classifier, or an SFC or any one of the service node devices in the service function chain, and the method of the foregoing Embodiment 1 may be implemented. Therefore, refer to the corresponding operation of the foregoing Embodiment 1 for the specific operation of the foregoing device. The content will not be described here.

One of ordinary skill in the art will appreciate that all or a portion of the steps of the above-described embodiments can be implemented using a computer program flow, which can be stored in a computer readable storage medium, such as on a corresponding hardware platform (eg, The system, device, device, device, etc. are executed, and when executed, include one or a combination of the steps of the method embodiments.

Optionally, all or part of the steps of the foregoing embodiments may also be implemented by using an integrated circuit, and the steps may be separately fabricated into integrated circuit modules, or multiple modules thereof or The steps are made into a single integrated circuit module. Thus, the invention is not limited to any specific combination of hardware and software.

The devices/function modules/functional units in the above embodiments may be implemented by a general-purpose computing device, which may be centralized on a single computing device or distributed over a network of multiple computing devices.

When each device/function module/functional unit in the above embodiment is implemented in the form of a software function module and sold or used as a stand-alone product, it can be stored in a computer readable storage medium. The above mentioned computer readable storage medium may be a read only memory, a magnetic disk or an optical disk or the like.

Industrial applicability

The embodiment of the invention can enable the operator to obtain the link information of the service chain simply and quickly, and diagnose and locate the link information of the service chain, thereby implementing various SFC OAMs simply and quickly.

Claims (12)

A business function chain (SFC) operation, management, and maintenance (OAM) method, including: When the source service node performs an OAM operation on the alias information, the source service node determines an SFC or a service function path that is bound to the alias information. The source service node performs an OAM operation on the determined SFC or the service function path, and generates a corresponding OAM message and sends the message to the destination service node of the OAM operation. The method of claim 1 further comprising: The source service node configures the alias information of the SFC or the service function path in the SFC domain, and the binding relationship between the SFC or the service function path corresponding to the alias information; or The source service node receives, from the universal service platform controller, the alias information of the SFC or the service function path in the SFC domain, and the binding relationship between the SFC or the service function path corresponding to the alias information; The alias information of the SFC or service function path is unique within the SFC domain. The method of claim 1 or 2, wherein the generating, by the source service node, the corresponding OAM message and transmitting the message to the destination service node includes: The source service node parses the OAM operation, and obtains the number M of service nodes that the OAM packet corresponding to the OAM operation needs to go through, and the determined SFC or the service function path after the source service node M service nodes are determined as destination service nodes, and M is a positive integer; The source service node sends the generated OAM message to the destination service node through the service node on the determined SFC or service function path. The method according to claim 3, wherein the number M of service nodes that the OAM message needs to go through exceeds the number of remaining service nodes after the start of the source service node on the determined SFC or service function path The source end node device determines the last service node on the determined SFC or service function path as the destination service node. The method of claim 4, wherein the source service node is a service classifier or any one of the service nodes on the SFC or service function path. A service node device, comprising: a first unit, configured to: when the service node device performs an operation, management, and maintenance (OAM) operation on the alias information, determine a service function chain (SFC) or a service function path that is bound to the alias information; as well as And a second unit, configured to: perform an OAM operation on the SFC or the service function path determined by the first unit, generate a corresponding OAM message, and send the message to the destination service node of the OAM operation. The apparatus of claim 6 further comprising: a third unit, configured to: configure an alias information for the SFC or the service function path in the SFC domain, and a binding relationship between the SFC or the service function path corresponding to the alias information; or Receiving and storing, from the general service platform controller, the alias information of the SFC or the service function path in the SFC domain, and the binding relationship between the SFC or the service function path corresponding to the alias information; The alias information of each SFC or service function path is unique within the SFC domain. The apparatus of claim 6 or 7, wherein the second unit comprises: a parsing module, configured to: parse the OAM operation, obtain the number M of service nodes that the OAM packet corresponding to the OAM operation needs to go, and determine the SFC or the service function path after the source service node The Mth service node is determined to be the destination service node, and M is a positive integer; And a sending module, configured to: send the generated OAM message from the source service node to the destination service node by using the determined service node on the SFC or the service function path. The device according to claim 8, wherein the parsing module is further configured to: the number of service nodes M to be experienced by the OAM message exceeds the determined SFC or the service function path from the source service node When the number of remaining service nodes after the start is determined, the last service node on the determined SFC or service function path is determined as the destination service node. The device of claim 9, wherein the service node device is any one of the service node devices on the SFC or service function path. A computer program for implementing the method of any of claims 1-5. A carrier for storing the computer program of claim 11.

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