It could be considered as: Performance versus Functional test.
For Channel Zapping the key metric is the max number of channels/subscribers supported. While Verification focuses more on whether the correct Channel is received for each subscriber (uses all 32 bits instead of just 2 for the Analyzer Filters). Although from a performance perspective they both can support the same channel change rates and/or "zap and view."
There are two configurable test types. The main difference between them is the way the IPTV host-side Analyzer filters are configured. The two tests are:
So one might use the Channel Verification Test to do deep analysis of a smaller number of hosts and channel ranges. As the SUT is characterized higher scale tests can be achieved by using the Channel Zapping Test.