Page 1382 - 5G Basics - Core Network Aspects

3 Signalling aspects

Message format:

< DS-REQ-Message > ::= < Message Header >
{ Service-Platform-Id }
{ BNG-Id }
{ Service-Instance-Id }
Meanings and explanations:

1) Service-Platform-Id uniquely specifies the service platform;
2) BNG-Id uniquely specifies the BNG element;
3) Service-Instance-Id uniquely identifies the service instance to be deleted. The service instance
is created by the CS-REQ message.
The response message to the DS-REQ message is defined as the delete service response (DS-RSP) message.

The DS-RSP message, indicated by the message type in the message header field, is sent by the BNG to the
service platform in response to the DS-REQ message. This message shows the handling results of the DS-REQ
message.
Message Format:

< DS-RSP-Message > ::= < Message Header >
{ Service-Platform-Id }
{ BNG-Id }
{ Result }
Meanings and explanations:
1) Service-Platform-Id uniquely specifies the service platform;

2) BNG-Id uniquely specifies the BNG element;
3) Result shows the handling result of deleting the service instance.

7.1.2.3 Chain service request message and response message
The chain service request (CHS-REQ) message, indicated by the message type in the message header field, is
sent by the services/service orchestrator to chain up services, i.e., to steer flow traffic to the specified service
handlers.

The CHS-REQ message may program the BNG to steer the traffic going out of its egress port to the ingress
port of the service node. The service instance sends the flow through the egress port of the service node
after the service instance handlings.

Message format:
< CHS-REQ-Message > ::= < Message Header >
{ Service-Platform-Id }
{ BNG-Id }
{ User-Id }
*{ Flow-Description }
{ Service-Id }
{ Service-Location }
{ Service-Instance-Id }

Meanings and explanations:
1) Service-Platform-Id uniquely specifies the service platform;
2) BNG-Id uniquely specifies the BNG element;
3) User-Id uniquely identifies the user/application that created the service;
4) Flow-Description distinguishes the flows to be handled. This contains several fields from
network flows. The flow description may be fields in the packet headers, and in some cases, the L4-
7 information may be needed. There may be multiple flow descriptions fields;

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