CN109995635B

CN109995635B - PTN networking system based on 5G carrying network

Info

Publication number: CN109995635B
Application number: CN201711484192.8A
Authority: CN
Inventors: 俞鑫; 陈炜; 徐维益
Original assignee: China Mobile Communications Group Co Ltd; China Mobile Group Shanghai Co Ltd
Current assignee: China Mobile Communications Group Co Ltd; China Mobile Group Shanghai Co Ltd
Priority date: 2017-12-29
Filing date: 2017-12-29
Publication date: 2021-08-20
Anticipated expiration: 2037-12-29
Also published as: CN109995635A

Abstract

The invention provides a PTN networking architecture based on a 5G bearer network, and belongs to the technical field of transmission networks. The architecture includes: a plurality of subsystems connected by a convergence ring; the convergence ring comprises two backbone convergence points, each subsystem comprises two convergence points and an access ring, and the convergence ring is connected with the access ring in each subsystem through the convergence point in each subsystem; the convergence point in each subsystem is connected with the backbone convergence point in the convergence ring. The networking architecture provided by the embodiment of the invention takes each access ring and the convergent point bearing each access ring as a subsystem, and connects the convergent point in each subsystem with the backbone convergent point in the convergent ring, so that the bandwidth shared by a plurality of access rings is changed into the bandwidth shared by each access ring independently, thereby avoiding the bandwidth waste caused by bandwidth sharing and improving the effective utilization rate of the bandwidth. In addition, it is easier to implement relative to current networking architectures.

Description

PTN networking system based on 5G carrying network

Technical Field

The invention relates to the technical field of transport networks, in particular to a PTN networking architecture based on a 5G bearer network.

Background

TD-LTE (TD-LTE, Time Division Long Term Evolution) is one of the mainstream technologies of IMT-Advance, and the mobile network can really enter the mobile broadband era. Compared with the existing 2G and 3G mobile communication system, TD-LTE puts higher requirements on the aspects of high bandwidth, low time delay, transverse forwarding, time synchronization ground transmission and the like of a return network.

First, bandwidth demand has evolved from several megabits, tens of megabits, during the 2G/3G period to several hundred megabits during the LTE period.

Secondly, LTE needs to provide flexible QoS and stricter end-to-end delay, and according to 3GPP specifications, for real-time game services with the strictest delay requirement, the end-to-end one-way delay from the user terminal to the server is 50ms, and the transmission delay therebetween needs to be within 10 ms.

Thirdly, LTE introduces the requirements of inter-neighboring base station interconnection (X2 interface) and base station multi-homing (S1-Flex), resulting in the transition of the backhaul network from a point-to-point aggregation type network to a point-to-multipoint or multipoint-to-multipoint routing type network, which cannot be met by the existing 2G/3G backhaul networks.

Fourthly, the air interface of the TD-LTE needs high-precision time synchronization, and requires very small deviation of air interface synchronization between different cells, so that a high-precision time synchronization signal needs to be transmitted in the TD-LTE backhaul network.

The PTN (Packet Transfer Network) can provide high-efficiency multi-service bearing, has strong protection, OAM and Network management functions, flexible statistical multiplexing and QoS (quality of service) capabilities, meets the requirements of TD-LTE (time division-Long term evolution) on high bandwidth and low time delay, and can also provide accurate time and frequency synchronization information transmission for a TD-LTE system. On the other hand, in the TD-LTE period, the OTN device may gradually sink to the metropolitan area convergence machine room, and the OTN needs to be further advanced to support the 1588v2 time synchronization technology, so as to implement the time synchronization ground transport networking of the OTN + PTN.

A TD-SCDMA (Time Division-Synchronous Code Division Multiple Access) wireless network was built since 2007. At present, a PTN three-layer architecture (backbone + convergence + access) is mainly adopted, and the technology based on MPLS-TPPTNL2 is utilized to carry TD services. At present, the PTN plane adopts L2+ L3 networking for carrying 4G LTE services. The bridge connection and the ground connection are carried through an OTN, 2 pairs of ground connection points, 8 pairs of bridge connection points and 100GE of link bandwidth of a convergence layer and the upper link bandwidth are arranged.

Fig. 1 is a schematic diagram of a PTN network architecture in the related art, and a traffic path between X2 stations can be as shown in fig. 2. In fig. 2, a link from a backbone aggregation point 1 to an aggregation point 1 carries services of access rings 1, 2, and 3, and a service path between X2 stations is: access-convergence-backbone convergence-core bridging-backbone convergence-access.

Since different rendezvous point group rings can share the bandwidth, and the shared bandwidth causes that the relay link close to the backbone rendezvous point needs to bear the access ring service under other rendezvous points, the bandwidth sharing can increase the load of the network relay link. In addition, in some scenarios in a 5G network, such as eMTC (enhanced Machine Type of Communication, internet of things based on LTE evolution) is mainly object-to-object Communication, and a Communication process is sensitive to time delay. However, the current PTN network architecture needs to transmit a network signal of a service based on a service path between X2 stations, so that the transmission delay is high.

Disclosure of Invention

In order to solve the above problems, the present invention provides a PTN networking architecture based on a 5G bearer network that overcomes or at least partially solves the above problems.

According to a first aspect of the present invention, there is provided a PTN networking architecture based on a 5G bearer network, including: a plurality of subsystems connected by a convergence ring; the convergence ring comprises two backbone convergence points, each subsystem comprises two convergence points and an access ring, and the convergence ring is connected with the access ring in each subsystem through the convergence point in each subsystem;

the convergence point in each subsystem is connected with the backbone convergence point in the convergence ring.

The networking architecture provided by the embodiment of the invention takes each access ring and the convergent point bearing each access ring as a subsystem, and connects the convergent point in each subsystem with the backbone convergent point in the convergent ring, so that the bandwidth shared by a plurality of access rings is changed into the bandwidth shared by each access ring independently, thereby avoiding the bandwidth waste caused by bandwidth sharing and improving the effective utilization rate of the bandwidth. In addition, it is easier to implement relative to current networking architectures.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention as claimed.

Drawings

Fig. 1 is a schematic diagram of a current PTN networking architecture;

fig. 2 is a schematic diagram of a service path under a current PTN networking architecture;

fig. 3 is a schematic diagram of a PTN networking architecture according to an embodiment of the present invention;

fig. 4 is a schematic diagram of a service path under a PTN networking architecture according to an embodiment of the present invention;

fig. 5 is a schematic diagram of a networking architecture in a large bandwidth service scenario according to an embodiment of the present invention;

fig. 6 is a schematic view of a service route under a PTN networking architecture according to an embodiment of the present invention.

Detailed Description

The following detailed description of embodiments of the present invention is provided in connection with the accompanying drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

In the current networking architecture scheme, different aggregation point group rings can share bandwidth, and sharing bandwidth causes a relay link close to a backbone aggregation point to need to carry access ring services under other aggregation points, so that bandwidth sharing can increase load of a network relay link. In addition, the current networking architecture scheme is more reasonable in the application of the X2 service with less than 5% traffic ratio and less sensitive to delay in the 4G LTE era. However, in some scenarios of the 5G network, such as eMTC (mass machine type communication), communication between objects is mainly sensitive to time delay, and the traffic proportion of the traffic between base stations to the whole is higher and higher. In the current networking architecture scheme, the service path between X2 stations can be as shown in fig. 1, specifically: access-convergence-backbone convergence-core bridging-backbone convergence-access, i.e., the service path between X2 stations is long, and it is difficult to meet the requirement of low delay. In addition, due to the shared bandwidth, the bandwidth requirements for each access ring are also difficult to meet.

In view of the above situation, an embodiment of the present invention provides a PTN networking architecture based on a 5G bearer network. The networking architecture includes: a plurality of subsystems connected by a convergence ring; the convergence ring comprises two backbone convergence points, each subsystem comprises two convergence points and an access ring, and the convergence ring is connected with the access ring in each subsystem through the convergence point in each subsystem; the convergence point in each subsystem is connected with the backbone convergence point in the convergence ring.

The Xn routing path is configured by L3VPN (three-layer private routing), namely, a three-layer tunnel is configured from an access point to a backbone convergent point, the access point is configured to a target base station working route and a protection route, and the backbone convergent point is responsible for scheduling and forwarding.

Based on the content of the foregoing embodiments, as an alternative embodiment, the aggregation point in each subsystem is connected to the backbone aggregation point in the aggregation ring through an optical fiber.

Based on the content of the foregoing embodiment, as an alternative embodiment, the aggregation points in each subsystem are connected to the backbone aggregation points in the aggregation ring in a one-to-one correspondence manner.

Specifically, a dual-uplink networking architecture based on a 5G bearer network may be as shown in fig. 3. Each subsystem comprises 2 convergent points and 3 access points, and the convergent ring comprises 2 backbone convergent points. For the subsystem positioned on the left side, the convergence point positioned on the upper part in the subsystem is connected with the backbone convergence point positioned on the left side, and the convergence point positioned on the lower part in the subsystem is connected with the backbone convergence point positioned on the right side. For the subsystem located at the lower part, the convergence point located at the left side in the subsystem is connected with the backbone convergence point located at the left side, and the convergence point located at the right side in the subsystem is connected with the backbone convergence point located at the right side. For the subsystem positioned on the right side, the convergence point positioned on the upper part in the subsystem is connected with the backbone convergence point positioned on the right side, and the convergence point positioned on the lower part in the subsystem is connected with the backbone convergence point positioned on the left side. The solid line in fig. 3 indicates a new link group 1, i.e. a new service routing link group, between the left access ring and the right access ring. The dashed lines in fig. 3 indicate the connections between the newly added link group 2 and the newly added link group 3, i.e., the different convergence points and the different backbone convergence points, respectively.

Taking PTN two-plane networking topology as an example, as shown in fig. 2, a relay link between a backbone aggregation point 1 and an aggregation point 1 in a current networking architecture needs to carry services of access rings 1, 2, and 3, that is, an original aggregation point networking network, and a relay link passing through the backbone aggregation point not only carries the service of the access ring but also carries the services of access rings under other aggregation points, so that the network load is heavy. In the dual-uplink networking architecture provided in the embodiment of the present invention, as shown in fig. 4, a relay link between a rendezvous point and a backbone rendezvous point does not bear access ring services of other rendezvous points any more, where a bandwidth of the relay link is changed from original sharing to exclusive sharing, that is, the rendezvous point is directly connected to the backbone rendezvous point, and the relay link between the rendezvous point and the backbone rendezvous point does not bear access ring services of other rendezvous points, so that network load can be reduced compared with the existing architecture.

For example, in a 5G eMBB scenario, an Xn scenario, and other large bandwidth service scenarios, it is difficult for the existing 10GE link of the access layer to meet the application requirement, so that the link bandwidth of the access layer can be adjusted to 25GE × N according to the actual situation, and some hot spot coverage areas in the urban area can be introduced into 100GE links to meet the bandwidth requirement of the actual service. The networking architecture under the above scenario can refer to fig. 4.

The networking architecture provided by the embodiment of the invention can enable each access ring to share the bandwidth independently by carrying out aggregation ring dual-uplink networking, and the bandwidth of the relay link used by each access ring can be dynamically adjusted according to the actual service load condition, thereby better meeting the bandwidth requirement of the service. In addition, since the ring in the service path fig. 2 is changed into a direct connection, the service delay can be reduced.

Based on the above disclosure of the embodiments, as an alternative embodiment, L3 sinks to each convergence point in each subsystem, and L3 edge sinks to each backbone convergence point in the convergence ring.

The carrier network can be further flattened by sinking L3 to each convergence point in each subsystem, and L3 edges to each backbone convergence point in the convergence ring. As shown in fig. 1, in the current networking architecture, the service paths between Xn stations are: access-convergence-backbone convergence-sub-backbone convergence-core bridging-backbone convergence-sub-backbone convergence-access. In the networking architecture provided by the embodiment of the present invention, as shown in fig. 3, since L3 sinks to each aggregation point in each subsystem, and the L3 edge sinks to each backbone aggregation point in the aggregation ring, the service path between Xn stations becomes: access-convergence-backbone convergence-access. That is, the number of devices passed by the Xn service path under the dual-uplink networking architecture is greatly reduced, thereby further reducing the service delay.

Based on the content of the foregoing embodiment, as an optional embodiment, for any subsystem, a relay link formed by connecting a convergence point in any subsystem with a backbone convergence point in a convergence ring is only used for carrying a service of an access ring in any subsystem.

In addition, compared with the original 4G L2+ L3 networking architecture, the number of Xn traffic reduction intermediate devices is 5, and the reduced transmission fiber distance is greater than 80 km. Because the packet forwarding delay inside the PTN device is 30us in general and the delay per kilometer of the optical fiber is 5us (the delay is calculated by 80 km), the networking architecture provided by the embodiment of the invention can reduce the delay by 550 us. For example, as shown in fig. 6, the traffic path from access ring 2 to access ring 3 may be shorter than the traffic path in fig. 2, as shown by the solid line in fig. 6.

The networking architecture provided by the embodiment of the invention can shorten the service path by connecting the convergence point in each subsystem with the backbone convergence point in the convergence ring, thereby shortening the service time delay.

Secondly, by adopting a dual-upper networking architecture, for any subsystem, when a relay link between one aggregation point and one backbone aggregation point in the subsystem breaks down, the relay link between the other aggregation point and the other backbone aggregation point can be continuously used for communication, so that the network robustness can be improved.

From time to time, for the ring traffic path in the current networking architecture, when any one of the relay links fails, the network may be largely broken down. The embodiment of the invention enables the link between the convergence point and the backbone convergence point to be shared independently by correspondingly connecting the convergence point in each subsystem with the backbone convergence point in the convergence ring one by one, thereby effectively improving the network robustness and reducing the network fault influence range.

All the above-mentioned optional technical solutions can be combined arbitrarily to form the optional embodiments of the present invention, and are not described herein again.

Finally, the method of the present application is only a preferred embodiment and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A PTN networking system based on a 5G bearer network is characterized by comprising: a plurality of subsystems connected by a convergence ring; the convergence ring comprises two backbone convergence points, each subsystem comprises two convergence points and an access ring, and the convergence ring is connected with the access ring in each subsystem through the convergence point in each subsystem;

the convergence point in each subsystem is connected with the backbone convergence point in the convergence ring;

l3 sinks to each convergence point in each subsystem, and L3 edge sinks to each backbone convergence point in the convergence ring.

2. The networking system of claim 1, wherein a convergence point in each subsystem is connected to a backbone convergence point in the convergence ring via an optical fiber.

3. The networking system of claim 1, wherein there is a one-to-one connection between a convergence point in each subsystem and a backbone convergence point in the convergence ring.

4. The networking system of claim 1, wherein for any subsystem, a relay link formed by a connection between a convergence point in the any subsystem and a backbone convergence point in the convergence ring is only used for carrying services of an access ring in the any subsystem.