The present disclosure provides a method for communication between a network device and a terminal device, where the network device stores a correspondence between a link-layer address and an IP address that are of the terminal device, and the method includes: obtaining, by the network device, a first link-layer address; determining whether a quantity of IP addresses corresponding to the first link-layer address reaches a threshold; if the quantity reaches the threshold, selecting an IP address from the IP addresses, where a quantity of selected IP addresses is not greater than the maximum quantity; saving a correspondence between the first link-layer address and the selected IP address; and sending, according to the selected IP address, a message to a terminal device having the first link-layer address, where the message is used to notify the terminal device whether an IP address is selected by the network device.

A packet processing method and a gateway device are provided. The method includes: A first gateway device receives, by using a first link, a first one-arm BFD echo packet returned by a network device, where the first one-arm BFD echo packet includes identification information, and the identification information is used to uniquely identify a second gateway device. The first gateway device determines, based on the identification information, to forward the first one-arm BFD echo packet to the second gateway device. The first gateway device sends the first one-arm BFD echo packet to the second gateway device. The network device is multi-homed connected to the first gateway device and the second gateway device. The first gateway device and the second gateway device form a multi-active gateway. According to the method, efficiency of detecting, by using a one-arm BFD echo session in a VXLAN multi-active gateway scenario is improved.

A packet processing method and a gateway device are provided. The method includes: A first gateway device receives, by using a first link, a first one-arm BFD echo packet returned by a network device, where the first one-arm BFD echo packet includes identification information, and the identification information is used to uniquely identify a second gateway device. The first gateway device determines, based on the identification information, to forward the first one-arm BFD echo packet to the second gateway device. The first gateway device sends the first one-arm BFD echo packet to the second gateway device. The network device is multi-homed connected to the first gateway device and the second gateway device. The first gateway device and the second gateway device form a multi-active gateway. According to the method, efficiency of detecting, by using a one-arm BFD echo session in a VXLAN multi-active gateway scenario is improved.

A network node in a service function chaining system receives a media stream from an endpoint device. The media stream is associated with a media session between the endpoint and at least one other endpoint. The network node determines a path for the media stream. The path includes an ordered list of functions to process the media stream. The network node determines a session identifier for the media stream and encapsulates the media stream with a header. The header includes an indication of the path and the session identifier.

Techniques are disclosed for the identification of applications from communication sessions of network traffic between client devices and the generation of application-specific metrics for network traffic associated with the applications. In one example, a router obtains metrics for a plurality of packets. The router determines a session of a plurality of sessions associated with each packet. For each determined session, the router generates metrics for the session from the metrics of the packets associated with the session and determines an application of a plurality of applications associated with the session. For each determined application, the router generates metrics for the application from the metrics of the sessions associated with the application and transmits, to a device, the metrics for the application. In some examples, the router generates the metrics for each application on a per-client, per-next-hop, or per-traffic class basis.

An aspect of the disclosure provides for a method for user equipment (UE) internet protocol (IP) address management. The method includes sending by an application function (AF), a request to a policy control function (PCF), the request including information identifying traffic and an indication that a UE IP address associated with the traffic should be preserved. The method further includes sending by the PCF, to a session management function (SMF) being responsible for managing a Protocol Data Unit (PDU) session associated with the traffic, a policy and charging control (PCC) rule including the indication. In some embodiments, the request is sent by the AF to the PCF via a network exposure function (NEF). In some embodiments, the method further includes managing, by the SMF, the UE IP address according to the PCC rule. In some embodiments, the managing includes preserving the UE IP address for a PDU session associated with the traffic. In some embodiments, the preserving includes preventing reselection of a protocol data unit (PDU) session anchor (PSA) to which the UE IP address is associated.

Systems, methods, and software are disclosed herein for routing in-bound communications to an infrastructure service. In an implementation, an infrastructure service receives a request from an end point for content associated with an origin. The service sends a connection request to the origin from an initial network address. After detecting a failure of the origin to respond to the connection request, the service sends multiple connection requests to the origin from different network addresses. Upon receiving one or more replies to the connection requests, the service identifies which reply was received first and a network address to which the reply was sent. The service proceeds to establish a connection with the origin using the identified network address and obtains the content from the origin over the connection. The infrastructure service may then send the content to the end point.

Systems, methods, and software are disclosed herein for routing in-bound communications to an infrastructure service. In an implementation, an infrastructure service receives a request from an end point for content associated with an origin. The service sends a connection request to the origin from an initial network address. After detecting a failure of the origin to respond to the connection request, the service sends multiple connection requests to the origin from different network addresses. Upon receiving one or more replies to the connection requests, the service identifies which reply was received first and a network address to which the reply was sent. The service proceeds to establish a connection with the origin using the identified network address and obtains the content from the origin over the connection. The infrastructure service may then send the content to the end point.

A communication method is provided. The method includes transmitting a network address assignment request to the network address translation entity after establishing a general packet radio service (GPRS) tunneling protocol (GTP) tunnel between the first user-plane function entity and the second user-plane function entity, such that the network address translation entity assigns a network address to the GTP tunnel, notifying the network address assigned by the network address translation entity to the GTP tunnel to the central data network, controlling a data packet to be transmitted by the edge service node to the central data network to be transmitted through the GTP tunnel, the network address translation entity replacing a source address of the data packet with the network address, and transmitting the data packet to the central data network after the data packet arrives at the network address translation entity.

A communication method is provided. The method includes transmitting a network address assignment request to the network address translation entity after establishing a general packet radio service (GPRS) tunneling protocol (GTP) tunnel between the first user-plane function entity and the second user-plane function entity, such that the network address translation entity assigns a network address to the GTP tunnel, notifying the network address assigned by the network address translation entity to the GTP tunnel to the central data network, controlling a data packet to be transmitted by the edge service node to the central data network to be transmitted through the GTP tunnel, the network address translation entity replacing a source address of the data packet with the network address, and transmitting the data packet to the central data network after the data packet arrives at the network address translation entity.