To Giltjr's point, the BIG-IP LTM IS as reverse proxy...that happens to also do load balancing. And by definition (roughly), a reverse proxy is a device/service that proxies requests from an unlimited number of clients to a limited number of servers. So from that perspective, a VIP (virtual server configuration) with an assigned pool (a pool of server resources) constitutes a very basic reverse proxy. The LTM is also application (protocol) aware, so it can technically be a reverse proxy at OSI layer 4 (UDP/TCP), 5/6 (SSL), and 7 (HTTP/FTP/SMTP/etc.).