Hi Yutaka-san, I am evaluating delegated 9.9.7 and have been noticing a peculiar problem for some time now. I have installed FTOSV filter in the following way: delegated -P4000 SERVER=https RELAY=vhost FTOSV=tcprelay://localhost:50002 Now and then, I notice that several requests do not show up in filter program that is listening on 50002. Delegated's logs also don't show them. However, the browser's web developer console shows them as successful. The network configuration is set so that all outgoing TCP packets with destination port 443 are forwarded to port 4000 - so, the traffic is always going through delegated. The browser's developer console doesn't show the "Via: delegated 9.9.7" attribute in the response headers for such requests. For all the requests that are logged by delegated and seen by my filter program, I see the "Via: ...." in the response headers. The browser is HTTP1.1 capable and is setting the "Connection: keep-alive" attribute. Hence, I am speculating the following: If the browser sends more than one request on the socket, delegated is unable to detect the second request onwards and doesn't pass them to my filter program. However, it does send them across to the server (because of the way the sockets are stitched?). Hence, the browser doesn't see any issue. Similar behavior is seen in the reverse path for the responses. That's probably why the "Via:" attribute is missing in the response headers of such requests. Can you please provide your comments on the issue and tell me whether I am doing something wrong? Thank you. C. Chigurupati