I would say this is more of a steganography challenge than a cryptography challenge per-se.<p><a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Steganography" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Steganography</a><p><a href="http:&#x2F;&#x2F;www.instructables.com&#x2F;id&#x2F;How-to-hide-one-image-in-another-An-introduction-&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.instructables.com&#x2F;id&#x2F;How-to-hide-one-image-in-ano...</a><p>If common image formats get through, then yes, there is a network broadcast format that you can use to securely communicate through the great firewall.