LONDON – The rise of video-on-demand means ad networks must step up and create environments where brands feel safe advertising, says one video ad tech exec. “Ad networks have a need to stay abreast of what technology is requiring,” global accounts SVP Jana Eisenstein of Videology tells Beet.TV. “Advertisers’ primary concern for VOD is brand safety and transparency. If you’re talking about programmatic buying and networks moving to an open exchange environment, having that safety and transparency is key. …