CLIAMS:1) A method of communication for establishing a path, applied in a PCEP (Path Computation Element Communication Protocol) system, the method comprises:
receiving, by a PCE (Path Computation Element), a path provision message transmitted by a PCC (Path Computation Client); wherein information of a LSP (Label Switched Path) is comprised in the path provision message;
sending, by the PCE, the path provision message to an ingress node, so that the LSP is established according to the information of the LSP in the path provision message.

2) The method according to claim 1, wherein the method further comprises:
receiving, by the PCE, a path report message transmitted by the ingress node; wherein status information of the LSP is comprised in the path report message;
sending, by the PCE, the path report message to the PCC.

3) The method according to claim 1 or 2, wherein the method further comprises:
receiving, by the PCE, a path teardown message transmitted by the PCC; wherein information of the LSP is comprised in the path teardown message;
sending, by the PCE, the path teardown message to the ingress node, so that the LSP is removed according to the information of the LSP in the path teardown message.

4) The method according to claim 1, before the PCE receives the path provision message, the method further comprising:
receiving, by the PCE, a path request message transmitted by the PCC;
sending, by the PCE, a path reply message to the PCC.

5) The method according to any one of the claims 1-4, wherein the PCC is a network arbiter, a network controller, an OSS (Operation Support System) or a NMS (Network Management System).

6) A method of communication for establishing path, applied in a PCEP (Path Computation Element Communication Protocol) system, the method comprises:
generating, by a PCC (Path Computation Client), a path provision message; wherein information of a LSP (Label Switched Path) is comprised in the path provision message;

sending, by the PCC, the path provision message to a PCE (Path Computation Element), so that the PCE sends the path provision message to an ingress node, and the LSP is established.

7) The method according to claim 6, wherein the method further comprises:
receiving, by the PCC, a path report message transmitted by the PCE; wherein the path report message is received by the PCE from the ingress node, and status information of the LSP is comprised in the path report message.

8) The method according to claim 6 or 7, wherein the method further comprises:
generating, by the PCC, a path teardown message; wherein information of the LSP is comprised in the path teardown message;
sending, by the PCC, the path teardown message to the PCE, so that the PCE sends the path teardown message to the ingress node, the LSP is removed according to the information of the LSP in the path teardown message.

9) The method according to claim 6, before the PCC sends the path provision message, the method further comprises:
sending, by the PCC, a path request message to the PCE;
receiving, by the PCC, a path reply message transmitted by the PCE.

10) A method of communication for establishing a path, applied in a PCEP (Path Computation Element Communication Protocol) system, the method comprises:
receiving, by an ingress node, a path provision message transmitted by a PCE (Path Computation Element); wherein the path provision message is received by the PCE from a PCC, and information of a LSP (Label Switched Path) is comprised in the path provision message;
establishing, by the ingress node, the LSP according to the information of the LSP in the path provision message.

11) The method according to claim 10, wherein the method further comprises:
sending, by the ingress node, a path report message to the PCE; wherein status information of the LSP is comprised in the path report message, so that the PCE sends the path report message to the PCC.

12) The method according to claim 10 or 11, wherein the method further comprises:
receiving, by the ingress node, a path teardown message transmitted by the PCE; wherein the path teardown message is received by the PCE from the PCC, and information of the LSP is comprised in the path teardown message;
removing, by the ingress node, the LSP according to the information of the LSP in the path teardown message.

13) A network apparatus, applied in a PCEP system, the network apparatus comprises:
a first receiving unit, configured to receive a path provision message transmitted by a PCC; wherein information of a LSP is comprised in the path provision message;
a first sending unit, configured to send the path provision message to an ingress node, so that the LSP is established according to the information of the LSP in the path provision message.

14) The network apparatus according to claim 13, wherein the network apparatus further comprises:
a second receiving unit, configured to receive a path report message transmitted by the ingress node; wherein status information of the LSP is comprised in the path report message;
a second sending unit, configured to send the path report message to the PCC.

15) The network apparatus according to claim 13 or 14, wherein the network apparatus further comprises:
a third receiving unit, configured to receive a path teardown message transmitted by the PCC; wherein information of the LSP is comprised in the path teardown message;
a third sending unit, configured to send the path teardown message to the ingress node, so that the LSP is removed according to the information of the LSP in the path teardown message.

16) The network apparatus according to claim 13, the network apparatus further comprises:
a fourth receiving unit, configured to receive a path request message transmitted by the PCC;
a fourth sending unit, configured to send a path reply message to the PCC.

17) A network apparatus, applied in a PCEP system, the network apparatus comprises:
a first generating unit, configured to generate a path provision message; wherein information of a LSP is comprised in the path provision message;
a first sending unit, configured to send the path provision message to a PCE, so that the PCE sends the path provision message to an ingress node, and the LSP is established.

18) The network apparatus according to claim 17, wherein the network apparatus further comprises:
a first receiving unit, configured to receive a path report message transmitted by the PCE; wherein status information of the LSP is comprised in the path report message.

19) The network apparatus according to claim 17 or 18, wherein the network apparatus further comprises:
a second generating unit, configured to generate a path teardown message; wherein information of the LSP is comprised in the path teardown message;
a second sending unit, configured to send the path teardown message to the PCE, so that the PCE sends the path teardown message to the ingress node, the LSP is removed according to the information of the LSP in the path teardown message.

20) The network apparatus according to claim 17, the network apparatus further comprises:
a third sending unit, configured to send a path request message to the PCE;
a third receiving unit, configured to receive a path reply message transmitted by the PCE.

21) A network apparatus, applied in a PCEP system, the network apparatus comprises:
a first receiving unit, configured to receive a path provision message transmitted by a PCE; wherein information of a LSP is comprised in the path provision message;
an establishing unit, configured to establish the LSP according to the information of the LSP in the path provision message.

22) The network apparatus according to claim 21, wherein the network apparatus further comprises:
a first sending unit, configured to send a path report message to the PCE; wherein status information of the LSP is comprised in the path report message.

23) The network apparatus according to claim 21 or 22, wherein the network apparatus further comprises:
a second receiving unit, configured to receive a path teardown message transmitted by the PCE; wherein information of the LSP is comprised in the path teardown message;
a removing unit, configured to remove the LSP according to the information of the LSP in the path teardown message.
,TagSPECI:FIELD OF THE INVENTION
This application relates to Traffic Engineering (TE) and in particular, to a method of communication for establishing a path and a network apparatus.

BACKGROUND
In TE networks, a Label Switched Path (LSP) can be established with a path provided by a Path Computation Client (PCC) and Path Computation Element (PCE).
Specifically, the PCC requests a path or route from the PCE, which calculates the path and forwards the calculated path information back to the PCC. Path Computation Element Communication Protocol (PCEP) is such a protocol designed specifically for communication between a PCC and PCE, or between two PCEs.
A PCC may use PCEP to send a path computation request (such as PCReq message) to a PCE, and the PCE may reply a message (such as PCRep message) with a set of computed paths if one or more paths can be found that satisfies the set of constraints.
Figure 1 is a topology diagram showing PCC and PCE are existed in a scenario. As shown in Figure 1, PCEP is used between a PCC and a PCE.
A PCE may be a stateless PCE, and this stateless PCE does not maintain path after calculation. Or, a PCE may be a stateful PCE, and this stateful PCE maintains the status of the LSP. On the other hand, a PCC may be an ingress router; or, a PCC may be a network arbiter, a network controller, an Operation Support System (OSS).
Figure 2 is a topology diagram showing a structure of cross stratum. A PCE can be used as an evolutionary mechanism to achieve in a Software Driven Network (SDN). As shown in Figure 2, a PCE can also be used by network arbiters in cross stratum path computation, where an arbiter requests the PCE to compute and maintain paths in a stateful PCE environment.
Figure 3 is a topology diagram showing the setup process for a path. As shown in Figure 3, a Network Management System (NMS) is used to setup the path.
As shown in Figure 2 and Figure 3, once the arbiter (Or orchestrator) has decided on a path, the path can be established by use of the NMS which sends a message to an ingress router to configure a tunnel.
However, the applicant found that: When a stateful PCE is used along with a PCC wich is a network arbiter or a network controller or an OSS, the PCC is not an ingress router, this means the PCC and the ingress router are two different entities.
Furthermore, the ingress router is the owner of the tunnel even when it has delegated to a stateful PCE. The ingress router will need to recalculate a path using Constraint Shortest Path First (CSPF), even if the PCE has already computed the path, but this is wasteful as the path is already available.

[Reference 1] “Path Computation Element (PCE) Communication Protocol (PCEP)” , RFC 5440.
[Reference 2] “A Backward-Recursive PCE-Based Computation (BRPC) Procedure to Compute Shortest Constrained Inter-Domain Traffic Engineering Label Switched Paths”, RFC 5441.
[Reference 3] “Encoding of Objective Function in the Path Computation Element Communication Protocol (PCEP)”, RFC 5541.
[Reference 4] “A Path Computation Element based architecture”, RFC 4655.
[Reference 5]“PCEP extension for stateful PCE”, [draft-ietf-pce-stateful- pce-01].
[Reference 6] “Applicability of stateful PCE”, [draft-zhang-pce-stateful- pce-app-01].
[Reference 7] “Cross Stratum Optimization based Path Computation”, [draft-dhody-pce-cso-enabled-path-computation-01].

SUMMARY
Embodiments of the present invention pertain to a method of communication for establishing a path and a network apparatus. The object of the invention is to let a PCE ultimately own a tunnel, and an ingress router will need not to recalculate a path corresponding to the tunnel.
According a first aspect of the embodiments of the present invention, a method of communication for establishing a path is provided, wherein the method is applied in a PCEP system, the method includes:
receiving, by a PCE, a path provision message transmitted by a PCC; wherein information of a LSP is comprised in the path provision message;
sending, by the PCE, the path provision message to an ingress node, so that the LSP is established according to the information of the LSP in the path provision message.
According another aspect of the embodiments of the present invention, wherein the method further includes:
receiving, by the PCE, a path report message transmitted by the ingress node; wherein the status of the LSP is comprised in the path report message;
sending, by the PCE, the path report message to the PCC.
According another aspect of the embodiments of the present invention, wherein the method further includes:
receiving, by the PCE, a path teardown message transmitted by the PCC; wherein information of the LSP is comprised in the path teardown message;
sending, by the PCE, the path teardown message to the ingress node, so that the LSP is removed according to the information of the LSP in the path teardown message.
According another aspect of the embodiments of the present invention, before the PCE receives the path provision message, the method further includes:
receiving, by the PCE, a path request message transmitted by the PCC;
sending, by the PCE, a path reply message to the PCC.
According another aspect of the embodiments of the present invention, wherein the PCC is a network arbiter, a network controller, an OSS or a NMS.
According a second aspect of the embodiments of the present invention, a method of communication for establishing a path is provided, wherein the method is applied in a PCEP system, the method includes:
generating, by a PCC, a path provision message; wherein information of a LSP is comprised in the path provision message;
sending, by the PCC, the path provision message to a PCE, so that the PCE sends the path provision message to an ingress node, the LSP is established.
According another aspect of the embodiments of the present invention, wherein the method further includes:
receiving, by the PCC, a path report message transmitted by the PCE; wherein the PCE receives the path report message from the ingress node, the status of the LSP is comprised in the path report message.
According another aspect of the embodiments of the present invention, wherein the method further includes:
generating, by the PCC, a path teardown message; wherein information of the LSP is comprised in the path teardown message;
sending, by the PCC, the path teardown message to the PCE, so that the PCE sends the path teardown message to the ingress node, the LSP is removed according to the information of the LSP in the path teardown message.
According another aspect of the embodiments of the present invention, before the PCC sends the path provision message, the method further includes:
sending, by the PCC, a path request message to the PCE;
receiving, by the PCC, a path reply message transmitted by the PCE.

According a third aspect of the embodiments of the present invention, a method of communication for establishing a path is provided, wherein the method is applied in a PCEP system, the method includes:
receiving, by an ingress node, a path provision message transmitted by a PCE; wherein information of a LSP is comprised in the path provision message, wherein the path provision message is sent from a PCC;
establishing, by the ingress node, the LSP according to the information of the LSP in the path provision message.
According another aspect of the embodiments of the present invention, wherein the method further includes:
sending, by the ingress node, a path report message to the PCE; wherein the status of the LSP is comprised in the path report message, so that the PCE sends the path report message to the PCC.
According another aspect of the embodiments of the present invention, wherein the method further includes:
receiving, by the ingress node, a path teardown message transmitted by the PCE; wherein information of the LSP is comprised in the path teardown message, wherein the path teardown message is sent from the PCC;
removing, by the ingress node, the LSP according to the information of the LSP in the path teardown message.
According a fourth aspect of the embodiments of the present invention, a network apparatus is provided, wherein the network apparatus is applied in a PCEP system, the network apparatus includes:
a first receiving unit, configured to receive a path provision message transmitted by a PCC; wherein information of a LSP is comprised in the path provision message;
a first sending unit, configured to send the path provision message to an ingress node, so that the LSP is established according to the information of the LSP in the path provision message.
According another aspect of the embodiments of the present invention, wherein the network apparatus further includes:
a second receiving unit, configured to receive a path report message transmitted by the ingress node; wherein the status of the LSP is comprised in the path report message;
a second sending unit, configured to send the path report message to the PCC.
According another aspect of the embodiments of the present invention, wherein the network apparatus further includes:
a third receiving unit, configured to receive a path teardown message transmitted by the PCC; wherein information of the LSP is comprised in the path teardown message;
a third sending unit, configured to send the path teardown message to the ingress node, so that the LSP is removed according to the information of the LSP in the path teardown message.
According another aspect of the embodiments of the present invention, wherein the network apparatus further includes:
a fourth receiving unit, configured to receive a path request message transmitted by the PCC;
a fourth sending unit, configured to send a path reply message to the PCC.
According a fifth aspect of the embodiments of the present invention, a network apparatus is provided, wherein the network apparatus is applied in a PCEP system, the network apparatus includes:
a first generating unit, configured to generate a path provision message; wherein information of a LSP is comprised in the path provision message;
a first sending unit, configured to send the path provision message to a PCE, so that the PCE sends the path provision message to an ingress node, the LSP is established.
According another aspect of the embodiments of the present invention, wherein the network apparatus further includes:
a first receiving unit, configured to receive a path report message transmitted by the PCE; wherein the the path report message is sent from the ingress node, the status of the LSP is comprised in the path report message.
According another aspect of the embodiments of the present invention, wherein the network apparatus further includes:
a second generating unit, configured to generate a path teardown message; wherein information of the LSP is comprised in the path teardown message;
a second sending unit, configured to send the path teardown message to the PCE, so that the PCE sends the path teardown message to the ingress node, the LSP is removed according to the information of the LSP in the path teardown message.
According another aspect of the embodiments of the present invention, the network apparatus further includes:
a third sending unit, configured to send a path request message to the PCE;
a third receiving unit, configured to receive a path reply message transmitted by the PCE.

According a sixth aspect of the embodiments of the present invention, a network apparatus is provided, wherein the apparatus is applied in a PCEP system, the network apparatus includes:
a first receiving unit, configured to receive a path provision message transmitted by a PCE; wherein information of a LSP is comprised in the path provision message, wherein the path provision message is sent from a PCC;
an establishing unit, configured to establish the LSP according to the information of the LSP in the path provision message.
According another aspect of the embodiments of the present invention, wherein the network apparatus further includes:
a first sending unit, configured to send a path report message to the PCE; wherein the status of the LSP is comprised in the path report message, so that the PCE sends the path report message to the PCC.
According another aspect of the embodiments of the present invention, wherein the network apparatus further includes:
a second receiving unit, configured to receive a path teardown message transmitted by the PCE; wherein information of the LSP is comprised in the path teardown message, wherein the path teardown message is sent from the PCC;
a removing unit, configured to remove the LSP according to the information of the LSP in the path teardown message.
The advantages of the present invention exist in that: a PCC sends a path provision message to a PCE, the PCE send the path provision message to an ingress node, so that the LSP is established according to the information of the LSP in the path provision message. Different from the prior art, the ingress node will not receive a message from a PCC (such as a NMS) but receive a path provision message from the PCE. So, the PCE will ultimately own the tunnel, and the ingress node will need not to recalculate the path.
These and further aspects and features of the present invention will be apparent with reference to the following description and attached drawings. In the description and drawings, particular embodiments of the invention have been disclosed in detail as being indicative of some of the ways in which the principles of the invention may be employed, but it is understood that the invention is not limited correspondingly in scope. Rather, the invention includes all changes, modifications and equivalents coming within the spirit and terms of the appended claims.

Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments and/or in combination with or instead of the features of the other embodiments.
It should be emphasized that the term “comprises/comprising” when used in this specification is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.
Many aspects of the invention can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present invention. To facilitate illustrating and describing some parts of the invention, corresponding portions of the drawings may be exaggerated in size, e.g., made larger in relation to other parts than in an exemplary device actually made according to the invention. Elements and features depicted in one drawing or embodiment of the invention may be combined with elements and features depicted in one or more additional drawings or embodiments. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views and may be used to designate like or similar parts in more than one embodiment.

BRIEF DESCRIPTION OF THE DRAWING
The drawings are included to provide further understanding of the present invention, which constitute a part of the specification and illustrate the embodiments of the present invention, and are used for setting forth the principles of the present invention together with the description. The same element is represented with the same reference number throughout the drawings.
In the drawings:
Figure 1 is a topology diagram showing PCC and PCE are existed in one scenario;
Figure 2 is a topology diagram showing a structure of cross stratum;
Figure 3 is a topology diagram showing the setup process for a path;
Figure 4 is a flowchart of the method of communication for establishing a path in accordance with an embodiment of the present invention;
Figure 5 is a topology diagram showing the process to configure a provision tunnel in accordance with an embodiment of the present invention;
Figure 6 is a flowchart of the method of communication for establishing a path in accordance with an embodiment of the present invention;

Figure 7 is another flowchart of the method of communication for establishing a path in accordance with an embodiment of the present invention;
Figure 8 is another flowchart of the method of communication for establishing path in accordance with an embodiment of the present invention;
Figure 9 is another flowchart of the method of communication for establishing path in accordance with an embodiment of the present invention;
Figure 10 is a flowchart of the method of communication for establishing path in accordance with an embodiment of the present invention;
Figure 11 is another flowchart of the method of communication for establishing path in accordance with an embodiment of the present invention;
Figure 12 is another flowchart of the method of communication for establishing path in accordance with an embodiment of the present invention;
Figure 13 is a flowchart of the method of communication for establishing path in accordance with an embodiment of the present invention;
Figure 14 is another flowchart of the method of communication for establishing path in accordance with an embodiment of the present invention;
Figure 15 is a schematic diagram of the network apparatus in accordance with an embodiment of the present invention;
Figure 16 is another schematic diagram of the network apparatus in accordance with an embodiment of the present invention;
Figure 17 is a schematic diagram of the network apparatus in accordance with an embodiment of the present invention;
Figure 18 is another schematic diagram of the network apparatus in accordance with an embodiment of the present invention;
Figure 19 is a schematic diagram of the network apparatus in accordance with an embodiment of the present invention;
Figure 20 is another schematic diagram of the network apparatus in accordance with an embodiment of the present invention;
Figure 21 is a schematic block diagram showing the systematic structure of the network apparatus of the embodiments of the present invention.

DETAILED DESCRIPTION
The many features and advantages of the embodiments are apparent from the detailed specification and, thus, it is intended by the appended claims to cover all such features and advantages of the embodiments that fall within the true spirit and scope thereof. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the inventive embodiments to the exact construction and operation illustrated and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope thereof.
In the present application, embodiments of the invention are described primarily in the context of a PCC or PCE. However, it shall be appreciated that the invention is not limited to the context of a PCC or PCE, and may relate to any type of appropriate electronic apparatus having the function of PCC or PCE.
The embodiments of the present invention are described as follows in reference to the drawings.

Embodiment 1
This embodiment of the present invention provides a method of communication for establishing a path, applied in a PCE side of a PCEP system.
Figure 4 is a flowchart of the method of communication for establishing a path in accordance with an embodiment of the present invention. As shown in Figure 4, the method includes:
Step 401, a PCE receives a path provision message transmitted by a PCC; wherein information of a LSP is included in the path provision message;
Step 402, the PCE sends the path provision message to an ingress node, so that the LSP is established according to the information of the LSP in the path provision message.
In this embodiment, the PCE may be a stateful PCE. The PCE is used not just for path computation but also for provisioning the LSP, and the PCE takes full ownership of a tunnel corresponding to the LSP.
In this embodiment, the PCC may be a network arbiter, a network controller, an OSS or a NMS. However it is not limited thereto, and particular implement entity may be determined as actually required.
Figure 5 is a topology diagram showing the process to configure a provision tunnel. As shown in Figure 5, a PCC (such as a network arbiter, a network controller, an OSS or a NMS) can send a path provision message to a PCE, and the PCE can send the path provision message to an ingress node to configure the provision tunnel.
In the prior art, PCEP requires a PCC to trigger a path (LSP) request and a PCE to provide reply. Even in stateful PCE environment, the PCC must delegate the path to the PCE, and the PCE never initiate path setup. However, in this embodiment, there is an extension to PCEP to let the PCE notify an ingress node (such as an ingress router) to establish the path, and the PCE ultimately own the tunnel to which the path corresponds.
In this embodiment, a new PCEP message (Path Provision Message, PCProv) is provided. Where, information of at least one LSP is included in the path provision message.
It can be seen from the above embodiment that: a PCC sends a path provision message to a PCE, the PCE send the path provision message to an ingress node, so that the LSP is established according to the information of the LSP in the path provision message. The ingress node receives the path provision message from the PCE. Since the PCE notify the ingress node to establish the path, the PCE will ultimately own the LSP, and the ingress node will need not to recalculate the path corresponding to the LSP.

Embodiment 2
This embodiment of the present invention provides a method of communication for establishing a path, applied in a PCE side. This embodiment is based on the embodiment 1 and the same content will not be described.
Figure 6 is a flowchart of the method of communication for establishing a path in accordance with an embodiment of the present invention, as shown in Figure 6, the method includes:
Step 601, a PCE receives a path provision message transmitted by a PCC; wherein information of a LSP is included in the path provision message.
Step 602, the PCE sends the path provision message to an ingress node, so that the LSP is established according to the information of the LSP in the path provision message.
As shown in Figure 6, the method may further include:
Step 603, the PCE receives a path report message transmitted by the ingress node; wherein status information of the LSP is included in the path report message;
Step 604, the PCE sends the path report message to the PCC, so that the status information of the LSP is fed back to the PCC.
In this embodiment, a new PCEP messages may be provided: a path provision message (PCProv). Where, information of at least one LSP is included in the path provision message.
In implement, a object may be used in the path provision message, and the object is used to identify the LSP; the identifier (ID) of the LSP is assigned by the network arbiter and it may be previously used to perform path computation. When the PCE forwards the provision message to the ingress node, the ingress node must carry the computed path as well as one or more constraints.

Table 1 has shown an example about format of a path provision message. As shown in talbe 1, a object may be included.

Table 1
The format of a PCProv message is as follows: ::= Where: ::= [] ::= [] Where: ::=[] ::= Where: ::= [] [] [] ::= []

Figure 7 is another flowchart of the method of communication for establishing a path in accordance with an embodiment of the present invention, as shown in Figure 7, the method includes:
Step 701, a PCE receives a path request message transmitted by a PCC.
Step 702, the PCE sends a path reply message to the PCC.
In this embodiment, no change required for existing PCEP messages like the Path Request Message (PCReq), the Path Reply Message (PCRep); and stateful messages like the Path Report Message (PCRpt) and path update message.
As shown in Figure 7, the method includes:
Step 703, the PCE receives a path provision message transmitted by the PCC; wherein information of a LSP is included in the path provision message.
Step 704, the PCE sends the path provision message to an ingress node, so that the LSP is established according to the information of the LSP in the path provision message.

As shown in Figure 7, the method may further include:
Step 705, the PCE receives a path report message transmitted by the ingress node; wherein status information of the LSP is included in the path report message;
Step 706, the PCE sends the path report message to the PCC.
In this embodiment, another new PCEP messages may be provided: a Path Teardown Message (PCTear). Where, information of at least one LSP is included in the path teardown message.
Figure 8 is another flowchart of the method of communication for establishing a path in accordance with an embodiment of the present invention, as shown in Figure 8, the method includes:
Step 801, a PCE receives a PCProv message transmitted by a PCC; wherein information of a LSP is included in the PCProv message.
Step 802, the PCE sends the PCProv message to an ingress node, so that the LSP is established according to the information of the LSP in the PCProv message.
As shown in Figure 8, the method may further include:
Step 803, the PCE receives a path report message transmitted by the ingress node; wherein status information of the LSP is included in the path report message;
Step 804, the PCE sends the path report message to the PCC.
As shown in Figure 8, the method may further include:
Step 805, the PCE receives a PCTear message transmitted by the PCC; wherein information of the LSP is included in the PCTear message;
Step 806, the PCE sends the PCTear message to the ingress node, so that the LSP is removed according to the information of the LSP in the PCTear message.
In implement, a object may be used in the PCTear message, and the object is used to identify the previously provisioned tunnel.
Table 2 has shown an example about format of a path teardown message. As shown in talbe 2, a object may be included.

Table 2
The format of a PCTear message is as follows: ::= Where: ::= []

Figure 9 is another flowchart of the method of communication for establishing a path in accordance with an embodiment of the present invention, as shown in Figure 9, the method includes:
Step 901, a PCE receives a path request message transmitted by a PCC.
Step 902, the PCE sends a path reply message to the PCC.
As shown in Figure 9, the method includes:
Step 903, the PCE receives a PCProv message transmitted by the PCC; wherein information of a LSP is included in the PCProv message.
Step 904, the PCE sends the PCProv message to an ingress node, so that the LSP is established according to the information of the LSP in the PCProv message.
As shown in Figure 9, the method may further include:
Step 905, the PCE receives a path report message transmitted by the ingress node; wherein the status of the LSP is included in the path report message;
Step 906, the PCE sends the path report message to the PCC.
As shown in Figure 9, the method may further include:
Step 907, the PCE receives a PCTear message transmitted by the PCC; wherein information of the LSP is included in the PCTear message;
Step 908, the PCE sends the PCTear message to the ingress node, so that the LSP is removed according to the information of the LSP in the PCTear message.
It can be seen from the above embodiment that: a PCC sends a path provision message to a PCE, the PCE send the path provision message to an ingress node, so that the LSP is established according to the information of the LSP in the path provision message. The ingress node receives the path provision message from the PCE. Since the PCE notify the ingress node to establish the path, the PCE will ultimately own the LSP, and the ingress node will need not to recalculate the path corresponding to the LSP.

Embodiment 3
This embodiment of the present invention provides a method of communication for establishing a path, applied in a PCC side of a PCEP system. This embodiment corresponds to the method of the above embodiment 1 or 2, and the same content will not be described.
Figure 10 is a flowchart of the method of communication for establishing a path in accordance with an embodiment of the present invention, as shown in Figure 10, the method includes:
Step 1001, a PCC generates a path provision message; wherein information of a LSP is included in the path provision message;
Step 1002, the PCC sends the path provision message to a PCE.
In this embodiment, the PCE may be a stateful PCE; the PCC may be a network arbiter, a network controller, an OSS or a NMS. However it is not limited thereto, and particular implement entity may be determined as actually required.
Figure 11 is another flowchart of the method of communication for establishing a path in accordance with an embodiment of the present invention, as shown in Figure 11, the method includes:
Step 1101, a PCC generates a path provision message; wherein information of a LSP is included in the path provision message;
Step 1102, the PCC sends the path provision message to a PCE.
As shown in Figure 11, the method may further include:
Step 1103, the PCC receives a path report message transmitted by the PCE; wherein the status of the LSP is included in the path report message.
As shown in Figure 11, the method may further include:
Step 1104, the PCC generates a path teardown message; wherein information of the LSP is included in the path teardown message;
Step 1105, the PCC sends the path teardown message to the PCE.
Figure 12 is another flowchart of the method of communication for establishing a path in accordance with an embodiment of the present invention, as shown in Figure 12, the method includes:
Step 1201, a PCC sends a path request message to a PCE;
Step 1202, the PCC receives a path reply message transmitted by the PCE.
As shown in Figure 12, the method includes:
Step 1203, the PCC generates a PCProv message; wherein information of a LSP is included in the PCProv message;
Step 1204, the PCC sends the PCProv message to the PCE.
As shown in Figure 12, the method may further include:
Step 1205, the PCC receives a path report message transmitted by the PCE; wherein status information of the LSP is included in the path report message.
As shown in Figure 12, the method may further include:
Step 1206, the PCC generates a PCTear message; wherein information of the LSP is included in the PCTear message;
Step 1207, the PCC sends the PCTear message to the PCE.
It can be seen from the above embodiment that: a PCC sends a path provision message to a PCE, the PCE send the path provision message to an ingress node, so that the LSP is established according to the information of the LSP in the path provision message. The ingress node receives the path provision message from the PCE. Since the PCE notify the ingress node to establish the path, the PCE will ultimately own the LSP, and the ingress node will need not to recalculate the path corresponding to the LSP.

Embodiment 4
This embodiment of the present invention provides a method of communication for establishing a path, applied in an ingress node side of a PCEP system. This embodiment corresponds to the method of the above embodiment 1 or 2, and the same content will not be described.
Figure 13 is a flowchart of the method of communication for establishing a path in accordance with an embodiment of the present invention, as shown in Figure 13, the method includes:
Step 1301, an ingress node receives a path provision message transmitted by a PCE; wherein information of a LSP is included in the path provision message;
Step 1302, the ingress node establishes the LSP according to the information of the LSP in the path provision message.
Figure 14 is another flowchart of the method of communication for establishing a path in accordance with an embodiment of the present invention, as shown in Figure 14, the method includes:
Step 1401, an ingress node receives a path provision message transmitted by a PCE; wherein information of a LSP is included in the path provision message.
Step 1402, the ingress node establishes the LSP according to the information of the LSP in the path provision message.
As shown in Figure 14, the method may further include:
Step 1403, the ingress node sends a path report message to the PCE; wherein status information of the LSP is comprised in the path report message.
As shown in Figure 14, the method may further include:
Step 1404, the ingress node receives a path teardown message transmitted by the PCE; wherein information of the LSP is comprised in the path teardown message;
Step 1405, the ingress node removes the LSP according to the information of the LSP in the path teardown message.
It can be seen from the above embodiment that: a PCC sends a path provision message to a PCE, the PCE send the path provision message to an ingress node, so that the LSP is established according to the information of the LSP in the path provision message. The ingress node receives the path provision message from the PCE. Since the PCE notify the ingress node to establish the path, the PCE will ultimately own the LSP, and the ingress node will need not to recalculate the path corresponding to the LSP.

Embodiment 5
This embodiment of the present invention further provides a network apparatus, applied in a PCE. This embodiment corresponds to the method of the above embodiment 1 or 2, and the same content will not be described.
Figure 15 is a schematic diagram of the network apparatus in accordance with an embodiment of the present invention. As shown in Figure 15, the network apparatus 1500 includes: a first receiving unit 1501 and a first sending unit 1502.
In this embodiment, the network apparatus may be a PCE. The function of establishing the a path may be integrated in the PCE; other parts of the PCE can refer to the existing technology and not be described in the present application. However, it is not limited thereto, and particular implement way may be determined as actually required.
Where, the first receiving unit 1501 is configured to receive a path provision message transmitted by a PCC; wherein information of a LSP is comprised in the path provision message; the first sending unit 1502 is configured to send the path provision message to an ingress node, so that the LSP is established according to the information of the LSP in the path provision message.
Figure 16 is another schematic diagram of the network apparatus in accordance with an embodiment of the present invention. As shown in Figure 16, the network apparatus 1600 includes: a first receiving unit 1501 and a first sending unit 1502. As described in above.
As shown in Figure 16, the network apparatus 1600 may further include: a second receiving unit 1603 and a second sending unit 1604.
Where, the second receiving unit 1603 is configured to receive a path report message transmitted by the ingress node; wherein status information of the LSP is comprised in the path report message; the second sending unit 1604 is configured to send the path report message to the PCC.
As shown in Figure 16, the network apparatus 1600 may further include: a third receiving unit 1605 and a third sending unit 1606.
Where, the third receiving unit 1605 is configured to receive a path teardown message transmitted by the PCC; wherein information of the LSP is comprised in the path teardown message; the third sending unit 1606 is configured to send the path teardown message to the ingress node, so that the LSP is removed according to the information of the LSP in the path teardown message.
As shown in Figure 16, the network apparatus 1600 may further include: a fourth receiving unit 1607 and a fourth sending unit 1608.
Where, the fourth receiving unit 1607 is configured to receive a path request message transmitted by the PCC; the fourth sending unit 1608 is configured to send a path reply message to the PCC.
It can be seen from the above embodiment that: a first receiving unit of a PCE receives a path provision message from a PCC, a first sending unit of the PCE send the path provision message to an ingress node. so that the LSP is established according to the information of the LSP in the path provision message. The ingress node receives the path provision message from the PCE. Since the PCE notify the ingress node to establish the path, the PCE will ultimately own the LSP, and the ingress node will need not to recalculate the path corresponding to the LSP.

Embodiment 6
This embodiment of the present invention further provides a network apparatus, applied in a PCC. This embodiment corresponds to the method of the above embodiment 3, and the same content will not be described.
Figure 17 is a schematic diagram of the network apparatus in accordance with an embodiment of the present invention. As shown in Figure 17, the network apparatus 1700 includes: a first generating unit 1701 and a first sending unit 1702.
In this embodiment, the network apparatus may be a PCC. The function of establishing a path may be integrated in the PCC; other parts of the PCC can refer to the existing technology and not be described in the present application. However, it is not limited thereto, and particular implement way may be determined as actually required.
Where, the first generating unit 1701 is configured to generate a path provision message; wherein information of a LSP is included in the path provision message; the first sending unit 1702 is configured to send the path provision message to a PCE.
Figure 18 is another schematic diagram of the network apparatus in accordance with an embodiment of the present invention. As shown in Figure 18, the network apparatus 1800 includes: a first generating unit 1701 and a first sending unit 1702. As described in above.
As shown in Figure 18, the network apparatus 1800 may further include: a first receiving unit 1803. Where, the first receiving unit 1803 is configured to receive a path report message transmitted by the PCE; wherein status information of the LSP is comprised in the path report message.
As shown in Figure 18, the network apparatus 1800 may further include: a second generating unit 1804 and a second sending unit 1805.
Where, the second generating unit 1804 is configured to generate a path teardown message; wherein information of the LSP is comprised in the path teardown message; the second sending unit 1805 is configured to send the path teardown message to the PCE.
As shown in Figure 18, the network apparatus 1800 may further include: a third sending unit 1806 and a third receiving unit 1807.
Where, the third sending unit 1806 is configured to send a path request message to the PCE; the third receiving unit 1807 is configured to receive a path reply message transmitted by the PCE.
It can be seen from the above embodiment that: a first generating unit of a PCC generates a path provision message, a first sending unit of the PCC sends the path provision message to a PCE, the PCE sends the path provision message to an ingress node. So, the LSP is established according to the information of the LSP in the path provision message. The ingress node receives the path provision message from the PCE. Since the PCE notify the ingress node to establish the path, the PCE will ultimately own the LSP, and the ingress node will need not to recalculate the path corresponding to the LSP.

Embodiment 7

This embodiment of the present invention further provides a network apparatus, applied in an ingress node. This embodiment corresponds to the method of the above embodiment 4, and the same content will not be described.
Figure 19 is a schematic diagram of the network apparatus in accordance with an embodiment of the present invention. As shown in Figure 19, the network apparatus 1900 includes: a first receiving unit 1901 and an establishing unit 1902.
In this embodiment, the network apparatus may be an ingress node. The function of establishing a path may be integrated in the ingress node; other parts of the ingress node can refer to the existing technology and not be described in the present application. However, it is not limited thereto, and particular implement way may be determined as actually required.
Where, the first receiving unit 1901 is configured to receive a path provision message transmitted by a PCE; wherein information of a LSP is comprised in the path provision message; the establishing unit 1902 is configured to establish the LSP according to the information of the LSP in the path provision message.
Figure 20 is another schematic diagram of the network apparatus in accordance with an embodiment of the present invention. As shown in Figure 20, the network apparatus 2000 includes: a first receiving unit 1901 and an establishing unit 1902. As described in above.
As shown in Figure 20, the network apparatus 2000 may further include: a first sending unit 2003. Where, the first sending unit 2003 is configured to send a path report message to the PCE; wherein status information of the LSP is included in the path report message.
As shown in Figure 20, the network apparatus 2000 may further include: a second receiving unit 2004 and a removing unit 2005.
Where, the second receiving unit 2004 is configured to receive a path teardown message transmitted by the PCE; wherein information of the LSP is comprised in the path teardown message; the removing unit 2005 is configured to remove the LSP according to the information of the LSP in the path teardown message.
It can be seen from the above embodiment that: a first receiving unit of an ingress node receives a path provision message, an establishing unit of the ingress node establishes a LSP according to the information of the LSP in the path provision message. The ingress node receives the path provision message from the PCE. Since the PCE notify the ingress node to establish the path, the PCE will ultimately own the LSP, and the ingress node will need not to recalculate the path corresponding to the LSP.
It should be understood that each of the parts of the present invention may be implemented by hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods may be realized by software or firmware that is stored in the memory and executed by an appropriate instruction executing system. For example, if it is realized by hardware, it may be realized by any one of the following technologies known in the art or a combination thereof as in another embodiment: a discrete logic circuit having a logic gate circuit for realizing logic functions of data signals, application-specific integrated circuit having an appropriate combined logic gate circuit, a Programmable Gate Array (PGA), and a field programmable gate array (FPGA), etc.
Figure 21 is a schematic block diagram showing the systematic structure of the network apparatus of the embodiments of the present invention. Such a figure is just exemplary and other types of structures may also be used for supplementing or replacing this structure, so as to implement the function of telecommunications or other functions.
As shown in Figure 21, the network apparatus 2100 may include a CPU 2101, a communication interface 2102, an input device 2103, a memory 2104 and an output device 2105.
Where, the CPU 2101 (also referred to as a controller or an operational control, which may include a microprocessor or other processing devices and/or logic devices) receives input and controls each part and operation of the network apparatus. The input device 2103 provides input to the CPU 2101. The input device 2103 may be for example a key or touch input device. The output device 2105 receives the data from the CPU 2101 and sends it to other apparatus.
The memory 2104 is coupled to the CPU 2101. The memory 2104 may be a solid memory, such as a read-only memory (ROM), a random access memory (RAM), and a SIM card, etc., may also be such a memory that stores information even when the power is interrupted, and may be optionally erased and provided with more data. Examples of such a memory are sometimes referred to as an EPROM, etc. The memory 2104 may also be certain other types of devices.
The communication interface 2102 may be a transmitter/receiver which transmitting and receiving signals via an antenna. The communication interface 2102 (transmitter/receiver) is coupled to the CPU 2101 to provide input signals and receive output signals, this being similar to the case in a conventional communication center.
The description or blocks in the flowcharts or of any process or method in other manners may be understood as being indicative of comprising one or more modules, segments or parts for realizing the codes of executable instructions of the steps in specific logic functions or processes, and that the scope of the embodiments of the present invention comprise other implementations, wherein the functions may be executed in manners different from those shown or discussed, including executing the functions according to the related functions in a substantially simultaneous manner or in a reverse order, which should be understood by those skilled in the art to which the present invention pertains.
The logic and/or steps shown in the flowcharts or described in other manners here may be, for example, understood as a sequencing list of executable instructions for realizing logic functions, which may be implemented in any computer readable medium, for use by an instruction executing system, device or apparatus (such as a system including a computer, a system including a processor, or other systems capable of extracting instructions from an instruction executing system, device or apparatus and executing the instructions), or for use in combination with the instruction executing system, device or apparatus.
The above literal description and drawings show various features of the present invention. It should be understood that those skilled in the art may prepare appropriate computer codes to carry out each of the steps and processes as described above and shown in the drawings. It should be also understood that all the terminals, computers, servers, and networks may be any type, and the computer codes may be prepared according to the disclosure to carry out the present invention by using the apparatus.
Particular embodiments of the present invention have been disclosed herein. Those skilled in the art will readily recognize that the present invention is applicable in other environments. In practice, there exist many embodiments and implementations. The appended claims are by no means intended to limit the scope of the present invention to the above particular embodiments. Furthermore, any reference to “a device to…” is an explanation of device plus function for describing elements and claims, and it is not desired that any element using no reference to “a device to…” is understood as an element of device plus function, even though the wording of “device” is included in that claim.
Although a particular embodiment has been shown and the present invention has been described, it is obvious that equivalent modifications and variants are conceivable to those skilled in the art in reading and understanding the description and drawings. Especially for various functions executed by the above elements (portions, assemblies, apparatus, and compositions, etc.), except otherwise specified, it is desirable that the terms (including the reference to “device”) describing these elements correspond to any element executing particular functions of these elements (i.e. functional equivalents), even though the element is different from that executing the function of an exemplary embodiment or embodiments illustrated in the present invention with respect to structure. Furthermore, although the a particular feature of the present invention is described with respect to only one or more of the illustrated embodiments, such a feature may be combined with one or more other features of other embodiments as desired and in consideration of advantageous aspects of any given or particular application.