Using Genetic Algorithms to create SSDP packets

for a part of my project we have to create request packets for dns, ssdp and ntp protocols. My professor has said to use genetic algorithms to come up with the field values for the request packet the response to which is the biggest.

I can see how we could achieve this for dns since we have a couple different fields for dns like qtype and qname among others but for ssdp requests, I don't think there are many fields? The only field I can think that can be changed in the ssdp request packet is the ST (search target) field so I'm not sure how I will select the parents in this situation. Any help would be appreciated!!