.. _example_interfaces_cellular_traffic_policy_checklinkhook:

###############
Check Link Hook
###############

This scenario shows how to attach a traffic policy to the `link` hook in a Cellular interface.
This hook is triggered at a very early stage of the network packet stack (level 2 layer).

.. image:: ../../google.svg
  :width: 800

**********************
Test Early Packet Drop
**********************

Description
===========

In DUT0, the cellular interface is configured with a
traffic policy to drop all incoming traffic at the link
stage and only allow ARP and UDP packets.

Scenario
========


.. osdx:tabset::
   :suite: checklinkhook
   :test: testearlypacketdrop
   :devices: vm:SDE,M10:M10-Smart,M2:M2,RS420:RS420,AresC640:AresC640,SDE11k:SDE11k,Atlas840:Atlas840,M20:M20,H5Rail:H5Rail