Throughout this document, the terms ingress and egress, when describing traffic direction, are always defined relative to the fabric. For example:
ingress direction describes packets moving into the switch fabric away from a port (on an adapter card)
egress direction describes packets moving from the switch fabric and into a port (on an adapter card)
When combined with the terms access and network, which are port and interface modes, the four traffic directions relative to the fabric are (see Figure: Egress and Ingress Traffic Direction):
access ingress direction describes packets coming in from customer equipment and switched toward the switch fabric
network egress direction describes packets switched from the switch fabric into the network
network ingress direction describes packets switched in from the network and moving toward the switch fabric
access egress direction describes packets switched from the switch fabric toward customer equipment
Throughout this guide, the terms access ingress/egress and service ingress/egress are interchangeable. This section (QoS Overview) uses the term access, and the following sections (beginning with QoS Policies Overview) use the term service.
