JP2016039467A - Packet priority control system and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow for priority processing of a packet, even when a network virtualization technique including SFC is applied to an existing IP network.SOLUTION: Priority processing of a packet based on the information for priority control in a header other than a SFC header of a received packet, e.g., an IP header, is possible by providing means for reading the information for priority control in a header other than a SFC header of that packet, when receiving a packet, and determining the priority thereof, and means for transferring the received packet based on the priority thus determined, respectively, in CL11, NF12 and SFF13.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a packet priority control technique, and more particularly to a packet priority control technique when a network virtualization technique including service function chaining is applied to a communication network.

  In recent years, NFV (Network Function Virtualization) / SDN (Software Defined Network) technology has attracted attention as a network virtualization technology, and Service Function Chaining (SFC) as a technology for effectively using a virtualized network ) Is attracting attention.

  The SFC controls the packet path of each user terminal (or its application) so as to pass through a plurality of service (function) devices (SF) arranged as virtual machines on the core network by virtualization. Thus, the service by these SFs is provided to the user terminal (or its application).

  FIG. 1 shows an example of a network configuration when a network virtualization technology including SFC is applied to a communication network. The SF described above is arranged as a virtual machine on a core network (Core NW) and realizes SFC. Therefore, each (function) device defined in Non-Patent Document 1 and Non-Patent Document 2, that is, CL (Classifier), NF (SFC Network Forwarder), and SFF (Service Function Forwarder) is a virtual machine or a real machine. Located on the core network.

  Here, the role of each device is as follows.

  The CL assigns / deletes an SFC identifier (SFC header or the like) for forwarding the packet to an appropriate NF and SFF. Also, if there is an IP network that does not understand the SFC header between CL and NF (between CL and SFF when NF does not exist), a header for tunnel connection between CL and NF is added to or deleted from the packet. To do.

  The NF forwards the packet from the core network to the SFF, and forwards the packet from the SFF to the core network. If there is a tunnel header or the like in the received packet, the packet is forwarded so that the SFC header can be referred to. The NF itself may forward the packet based on the SFC header. A pattern in which NF does not exist in the network and SFF also plays a role can be assumed.

  The SFF forwards the packet received from the NF (or the core network) to an appropriate SF based on the SFC header in the packet. At this time, if the transfer destination SF can recognize the SFC header, it forwards as it is, and if it cannot recognize it, it passes through a function such as proxy and forwards without the SFC header. Further, when the NF does not exist in the network, the above-described tunnel header is added / deleted.

  In addition, as an SF having a network-related service function such as a firewall, an existing real machine may be used as it is in addition to a virtual machine, and both an SF that understands an SFC header and an SF that does not understand an SFC header. Exists.

  FIG. 2 shows an example of a prioritization control technique in a conventional IP network. A packet distribution unit refers to a ToS field in an IP header of a transferred packet, and is a 3-bit value representing a priority therein. Packets are classified according to their precedence values and stored in a class-specific queue, and packets stored in a queue with high priority in the scheduler are output in preference to packets stored in queues with low priority. Thus, packet transfer with reduced delay and loss is performed.

  When network virtualization technology including SFC is applied to an existing IP network, even if there is a priority control mechanism in the IP network, SFC does not have a priority control mechanism. Since it cannot be processed with a certain degree of time, problems such as failure to satisfy the SLA (Service Level Agreement) of the network will occur.

In the present invention, in order to achieve the object,
As a device for realizing service function chaining for controlling a packet path to pass through a plurality of service devices arranged on the core network, a CL for adding an SFC header to the packet, and an SFC header in the packet A packet priority control system in a communication network in which at least an SFF that forwards the packet to an appropriate service device is mounted,
The CL and SFF are respectively
Means for reading the information for priority control in the header other than the SFC header of the packet and determining the priority when the packet is received;
Proposed is a packet priority control system comprising at least means for transferring the received packet based on the determined priority.

In the present invention, in order to achieve the object,
As a device for realizing service function chaining for controlling a packet path to pass through a plurality of service devices arranged on the core network, a CL for adding an SFC header to the packet, and an SFC header in the packet A packet priority control system in a communication network in which at least an SFF that forwards the packet to an appropriate service device is mounted,
CL is
Means for storing a value indicating priority in a field related to priority control of the SFC header;
CL and SFF are respectively
Means for reading the field related to priority control in the SFC header of the packet and determining its priority when receiving the packet;
Means for forwarding the received packet based on the determined priority;
Proposed is a packet priority control system comprising at least means for converting information in a field related to priority control in an SFC header into information for existing priority control.

  According to the present invention, even when network virtualization technology including SFC is applied to an existing IP network, information for priority control in the IP header or information for newly assigned priority control is used. It is possible to process packets preferentially.

Explanatory drawing which shows an example of a network structure at the time of applying NW virtualization technology including SFC to a communication network Explanatory drawing which shows an example of the priority control technique in the conventional IP network Explanatory drawing which shows 1st Embodiment of the packet priority control system of this invention Explanatory drawing of the priority control system in the first embodiment Explanatory drawing which shows an example of the operation | movement in 1st Embodiment. The sequence diagram which shows an example of the operation | movement in 1st Embodiment Explanatory drawing which shows 2nd Embodiment of the packet priority control system of this invention Explanatory drawing of the priority control system in the second embodiment Explanatory drawing which shows an example of the operation | movement in 2nd Embodiment. Sequence diagram showing an example of operation in the second embodiment

<First embodiment (first priority control method)>
FIG. 3 shows a first embodiment of the packet priority control system according to the present invention, in this case where network virtualization technology including SFC is applied to an IP network and information for priority control in the IP header is used. This shows the network configuration. The SF is arranged on the IP core network (IP Core NW) as a virtual machine, and each of the (function) devices CL11, NF12 and SFF13 for realizing the SFC is a virtual machine or a real machine. It is arranged on the IP core network as a machine.

As shown in FIG. 4, each of CL11, NF12, and SFF13 constituting this embodiment is
Means for reading a header other than the SFC header of the packet, here, information for priority control in the IP header and determining its priority when receiving the packet;
Means for forwarding the received packet (and processing other network-related functions) based on the determined priority.

  Note that these means are realized by a software program that operates on a server (computer) in a virtual machine, and by a software program that operates on hardware or a computer that constitutes the real machine in a real machine.

  Next, an example of a specific operation according to the embodiment of the present invention will be described with reference to FIGS.

  Here, although functionally the same, for distinction, CL11 is CL # 1 and CL # 2, NF12 is NF # 1 and NF # 2, SFF13 is SFF # 1 and SFF # 2. Yes, the IP core network is connected to a terminal through CL # 1, and is connectable to a server (srv) on the Internet through CL # 2. In addition, the SFs incorporated in the SFC of this example are SF # 1 and SF # 2, and the IP core network between CL and NF is assumed to be an IP network, and the SFC header is encapsulated by GRE on this IP core network It shall be.

  (1) The terminal performs communication for the server.

  (2) CL # 1 receives a packet transmitted from the terminal and adds an SFC header.

  (3) CL # 1 determines the priority of the packet based on the priority control field in the IP header, and performs transfer processing. In order to forward the packet to the IP core network, encapsulation is performed with GRE. At this time, the priority control field in the IP header in the GRE header is set by referring to the priority control field in the original IP header.

  (4) NF # 1 decapsulates the GRE, determines the priority of the packet based on the priority control field in the IP header, and forwards the packet to SFF # 1.

  (5) SFF # 1 determines the priority of the packet based on the priority control field in the IP header, and forwards the packet to an appropriate SF, here SF # 1, based on the SFC header. At this time, the SFC header is removed.

  (6) SF # 1 processes the packet and forwards the packet to SFF # 1.

  (7) SFF # 1 adds the SFC header to the packet again, determines the priority of the packet based on the priority control field in the IP header, and forwards the packet to NF # 1.

  (8) NF # 1 determines the priority of the packet based on the priority control field in the IP header and forwards the packet to NF # 2. At this time, the packet is encapsulated with GRE.

  (The process between NF # 2 to SF # 2 to CL # 2 is the same as above).

  (9) CL # 2 determines the priority of the packet based on the priority control field in the IP header, and forwards the packet to the Internet. At this time, the SFC header is removed.

  (10) The packet reaches the server (return communication from srv is omitted).

<Second embodiment (second priority control method)>
FIG. 7 shows a second embodiment of the packet priority control system according to the present invention, in this case where the network virtualization technology including SFC is applied to the IP network and information for priority control in the SFC header is used. This shows the network configuration. The SF is arranged as a virtual machine on the IP core network (IP Core NW), and each (function) device CL21, NF22, and SFF23 for realizing the SFC is a virtual machine or a real machine. It is arranged on the IP core network as a machine.

  The CL 21 constituting this embodiment has means for storing a value indicating priority in a field related to priority control of the SFC header.

Here, the field related to priority control of the SFC header may be a newly defined field or an existing field such as a Context header. In addition, a function that enables cooperation with other mechanisms, for example, (a) a function that analyzes a field related to priority control in the IP header and stores a compatible value in a field related to priority control of SFC,
(B) A function capable of setting / changing parameters for priority control in the SFC header in cooperation with the controller and database.
May be provided.

Moreover, as shown in FIG. 8, CL21, NF22, and SFF23 which comprise this Embodiment, respectively,
Means for reading the information for priority control in the SFC header of the packet and determining its priority when receiving the packet;
Means for forwarding (and processing other network related functions) the received packet based on the determined priority;
Means for converting field information relating to priority control in the SFC header into existing information for priority control.

  Each means described above is realized by a software program that runs on a server (computer) in a virtual machine, and by a software program that runs on hardware or a computer that constitutes the real machine in a real machine.

  Next, an example of a specific operation according to the embodiment of the present invention will be described with reference to FIGS.

  Here, in order to distinguish, CL21 is CL # 1 and CL # 2, NF22 is NF # 1 and NF # 2, SFF23 is SFF # 1 and SFF # 2. Yes, the IP core network is connected to a terminal through CL # 1, and is connectable to a server (srv) on the Internet through CL # 2. In addition, the SFs incorporated in the SFC of this example are SF # 1 and SF # 2, and the IP core network between CL and NF is assumed to be an IP network, and the SFC header is encapsulated by GRE on this IP core network It shall be.

  Further, in this example, it is assumed that the above-described (a) SFC header priority control and IP header priority control mechanism are linked to each other, and the priority control value to be set is stored in the database in the CL 21.

  (1) The terminal performs communication for the server.

  (2) CL # 1 receives a packet transmitted from the terminal, refers to a database in the CL, sets a priority control field in the SFC header, and adds an SFC header to the packet.

  (3) CL # 1 determines the priority of the packet based on the priority control field in the SFC header, and performs transfer processing. In order to forward the packet to the IP core network, encapsulation is performed with GRE. At this time, the priority control field in the SFC header is referred to, and the priority control field in the IP header in the GRE header is set.

  (4) NF # 1 decapsulates the GRE, determines the priority of the packet based on the priority control field in the SFC header, and forwards the packet to SFF # 1.

  (5) SFF # 1 discriminates the priority of the packet based on the priority control field in the SFC header, and forwards the packet to an appropriate SF, here SF # 1, based on the SFC header. At this time, the SFC header is removed.

  (6) SF # 1 processes the packet and forwards the packet to SFF # 1.

  (7) SFF # 1 adds the SFC header to the packet again, determines the priority of the packet based on the priority control field in the SFC header, and forwards the packet to NF # 1.

  (8) NF # 1 determines the priority of the packet based on the priority control field in the SFC header, and forwards the packet to NF # 2. At this time, the packet is encapsulated with GRE.

  (The processing between NF # 2 to SF # 2 to CL # 2 is the same as above).

  (9) CL # 2 determines the priority of the packet based on the priority control field in the SFC header, and forwards the packet to the Internet. At this time, the SFC header is removed.

  (10) The packet reaches the server (return communication from srv is omitted).

  Note that the network configuration, functions, names, and the like of the above-described embodiments are examples, and are not limited to those described here.

  11, 21: CL, 12, 22: NF, 21, 23: SFF.

Paul Quinn et al., “Draft-quinn-sfc-arch”, [online], May 5, 2014, IETF, [Search July 17, 2014], Internet <URL: http: // datatracker .ietf.org / doc / draft-quinn-sfc-arch / ＞ Paul Quinn et al., “Draft-quinn-sfc-nsc”, [online], July 3, 2014, IETF, [searched July 17, 2014], Internet <URL: http: // datatracker .ietf.org / doc / draft-quinn-sfc-nsh / ＞

Claims (6)

As a device for realizing service function chaining for controlling a packet path to pass through a plurality of service devices arranged on the core network, a CL for adding an SFC header to the packet, and an SFC header in the packet A packet priority control system in a communication network in which at least an SFF that forwards the packet to an appropriate service device is mounted,
The CL and SFF are respectively
Means for reading the information for priority control in the header other than the SFC header of the packet and determining the priority when the packet is received;
A packet priority control system comprising: at least means for transferring the received packet based on the determined priority. As a device for realizing service function chaining for controlling a packet path to pass through a plurality of service devices arranged on the core network, a CL for adding an SFC header to the packet, and an SFC header in the packet A packet priority control system in a communication network in which at least an SFF that forwards the packet to an appropriate service device is mounted,
CL is
Means for storing a value indicating priority in a field related to priority control of the SFC header;
CL and SFF are respectively
Means for reading the field related to priority control in the SFC header of the packet and determining its priority when receiving the packet;
Means for forwarding the received packet based on the determined priority;
A packet priority control system comprising at least means for converting information on a field related to priority control in an SFC header into information for existing priority control. Means for storing a value indicating the priority in the priority control field of the SFC header,
Analyzes the field related to priority control in the IP header and stores a compatible value in the field related to priority control of the SFC, or sets parameters for priority control in the SFC header in cooperation with the controller and database The packet priority control system according to claim 2, further comprising a function that can be changed. As a device for realizing service function chaining for controlling a packet path to pass through a plurality of service devices arranged on the core network, a CL for adding an SFC header to the packet, and an SFC header in the packet A packet priority control method in a communication network in which at least an SFF that forwards the packet to an appropriate service device is implemented,
The CL and SFF are respectively
When receiving a packet, reading information for priority control in a header other than the SFC header of the packet and determining its priority;
And at least a step of transferring the received packet based on the determined priority. As a device for realizing service function chaining for controlling a packet path to pass through a plurality of service devices arranged on the core network, a CL for adding an SFC header to the packet, and an SFC header in the packet A packet priority control method in a communication network in which at least an SFF that forwards the packet to an appropriate service device is implemented,
CL includes a step of storing a value indicating the priority in a field related to priority control of the SFC header,
CL and SFF are respectively
When receiving a packet, reading a field related to priority control in the SFC header of the packet and determining its priority;
Forwarding the received packet based on the determined priority;
A packet priority control method comprising: at least a step of converting information on a field related to priority control in an SFC header into information for existing priority control. The step of storing a value indicating priority in the priority control field of the SFC header is as follows:
Analyzing the field related to priority control in the IP header and storing the compatible value in the field related to SFC priority control, or setting parameters for priority control in the SFC header in cooperation with the controller and database The packet priority control method according to claim 5, further comprising a changeable step.

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