Network Control System Configuration Technologies for Advanced Network Operation

3.1 Communication delay and packet loss

Communication delay for most of the services specified in 5G (5th-generation mobile communication system) is in the millisecond range, and the APN is expected to have stricter delay requirements in the microsecond range. Therefore, even higher accuracy is required in delay measurement. Scalability will also be necessary for network-quality management of carrier networks.

To solve these problems, we are researching and developing high-accuracy inline monitoring technology, which uses segment routing (SR) to generate monitoring packets. By connecting a monitoring system that is based on our technology to a carrier network, it will be able to immediately calculate all monitoring routes, generate monitoring packets, and send them. By using the Data Plane Development Kit (DPDK), delay measurement in microseconds (nanosecond precision as resolution) can be achieved. Unlike peer-to-peer probe measurement, which is a common method of measuring delay, it is possible to achieve network-carrier scale by only connecting to a single location on the network (Fig. 3) (without installing measurement equipment at multiple locations in the network).

Fig. 3. Overview of high-accuracy inline monitoring technology.

The high-accuracy inline monitoring technology can be applied to monitoring VPN services because it can measure the communication delay of the desired route (e.g., user communication route).

3.2 Traffic-flow statistics

In current carrier networks, many user communications with different bandwidth requirements are transported in the network. Therefore, it is becoming increasingly important for network operation to confirm whether user communication can be transported as requested within the network.

We therefore developed a technology called Fast xFlow Proxy [2], which collects header samples and raw packets from routers and executes protocol analysis, grouping, header removal, and traffic measurement. Various flow analyses are possible by using the results as traffic-flow statistics as input for commercial analysis technologies (Fig. 4). The advantage of this technology is that these processes are accelerated using a field-programmable gate array (FPGA) and DPDK. The monitoring of carrier-level large-capacity communications will be achieved by deploying appropriate functions in both hardware and software, passing metadata from hardware to software, and providing load balancing functions to improve scalability.

Fig. 4. Outline of flow-statistics collection (Fast xFlow Proxy).

By using this technology, it is possible to monitor the bandwidth of user communication and the route actually passed through, for example, in a network that provides a VPN to users on SR-MPLS (multi-protocol label switching). By comparing the current and past traffic volume of a certain user’s communication and by comparing the traffic volume between users, it will be possible to identify the cause of a communication failure, i.e., the user network or carrier network.

1. Dense accommodation of subscribers by using the resource pooling technology

2. Rapid service recovery

3. Easy control for various network nodes

4.1 Dense accommodation of subscribers by using the resource pooling technology

In a current commercial network, network providers consistently use the identifier of physical assignment from the subscriber-management and network-resource management systems to the network nodes. It achieves accurate accommodation with millions of subscribers. However, the consistent use of the physical identifier is a problem in that the use of the subscriber accommodation resource is not efficient, which leads to increased capital expenditure. The Network Control Platform Technology pools the resources of the network nodes and executes centralized management. The subscriber-management systems use the identifier of the virtual assignment, and this technology determines the physical assignment for efficient accommodation and translates the identifier of the virtual assignment to that of the physical assignment in accordance with the accommodation information.

4.2 Rapid service recovery

In the event of a large-scale failure such as a building-affected disaster, service provision may be suspended due to the network-node restriction in current services. The Network Control Platform Technology enables rapid service recovery by controlling network changes to other network nodes within an available resource in the pooled resources.

4.3 Easy control for various network nodes

The subscriber accommodation in the network of multi-vendor nodes has the problem that the interface implementation and configuration format of each network node differs, which requires individual configuration. The Network Control Platform Technology enables multi-vendor control by consistent configuration with a plug-in module and by flexible translation of the virtual and physical assignment identifiers.

5.1 Control technology using network information

Network control requires fast and appropriate recovery from sudden network failures. Therefore, we are investigating the automation of network control using real-time data from the Network Information Collection and Analysis Platform Technology. For example, when allocating traffic to optimal routes to minimize quality degradation in a real network, it is necessary to consider the reduction in route-calculation time as well as the impact on uncontrolled communications. Therefore, we implemented logic to optimize network utilization per application and minimize the communication impact of route variations. In addition to this traffic engineering, we are also considering active processing for specific traffic. This technology will automate the process from information collection and analysis to network control, which will drastically reduce operational costs.

5.2 Inter-network connection control technology

To extend the target network for control, we are investigating interconnecting different networks. Current networks are independent of fixed and mobile networks or cost-efficient networks that accommodate multiple users and quality-guaranteed networks for business, making it difficult to provide a flexible combination to meet user needs. Therefore, we are developing technology to control the connection points between networks that guarantees independence among users and technology to integrate and manage each network resource across different networks to determine the optimal interconnection point locations such as low latency routes. With these technologies, we aim to provide a secure, one-stop service for network interconnection.

5.3 White box control technology

This control technology will extend network-construction automation and network functionality for white box switches. It will enable automation of user VPN construction by managing topology information and dispatchable resource status. It will also enable the deployment of information-collection agents at arbitrary locations to extend network testing and information collection.