Which of the following policies does NOT exist by default on a network port?

Network policies are applied to Layer 3 network interfaces (IP interfaces), not directly to the Layer 2 network port itself. While a system-wide default network policy (ID 1) exists, it is only associated with a port after a network interface has been explicitly configured on that port. In contrast, default network queue policies and slope policies are fundamental to the hardware's traffic handling structure. A default network queue policy is applied to the MDA on ingress and the port on egress, and a default slope policy is applied to the ingress queues, all without requiring the configuration of a higher-level logical entity like an IP interface.

B. A default slope policy is automatically applied to ingress queues on a network port for Weighted Random Early Detection (WRED) buffer management.
C. A default network queue policy is automatically applied to the corresponding MDA on ingress to define the default set of forwarding plane queues.
D. A default network queue policy is automatically applied to the network port on egress to define the default set of eight egress queues.

1. Nokia 7750 SR OS Quality of Service Guide, Release 21.10.R1, Section: QoS Policy Entities

Page 51, "Default QoS Policies": This section explicitly states, "There are default network queue policies... The default policies are applied to the appropriate objects at creation and cannot be deleted." This confirms that default network queue policies for ingress (MDA) and egress (port) exist by default, making options C and D incorrect.

Page 51, "Default Slope Policies": The guide states, "A default slope policy is applied to each queue." This confirms that a slope policy exists by default for the port's ingress queues, making option B incorrect.

Page 113, "Network Policy Overview": This section details that network policies are applied to network interfaces. It states, "The default network policy is policy-id 1 and it is applied to all network interfaces." This confirms the policy is for the interface, a logical L3 construct, not the L2 port itself. The port must first be configured with an interface for this policy to be applied, meaning it does not exist on the port by default.