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When a service is bind to an interface, Interface Manager programs the service dispatcher table with a rule to match on the interface data-plane-id and the service-index (based on priority) and the instruction-set provided by the service/application. Every time when the packet leaves the dispatcher table the service-index (in metadata) is incremented to match the next service rule when the packet is resubmitted back to dispatcher table. if the service-mode is ingress, ingress dispatcher is programmed or else if the service-mode-egress is configured egress-dispatcher table is programmed.
Binding services on interface
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Currently Interface Manager supports service binding on port ingress only. However, there are services that need packet processing on the egress, before sending the packet out to particular port/interface. To accommodate this, interface manager will be enhanced to support egress service binding also. This will be achieved by introducing a new “egress dispatcher table” at the egress of packet pipeline before the interface egress groups.
On different application request, Interface Manager returns the egress actions for interfaces. Service modules program use these actions to send the packet to particular interface. Generally, these egress actions include sending packet out to port or appropriate interface egress group. With the inclusion of the egress dispatcher table the egress actions for the services would be to
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