<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><br class=""><div><blockquote type="cite" class=""><div class="">On Dec 7, 2015, at 3:14 PM, Zeinab <<a href="mailto:z.rezaiefar@yahoo.com" class="">z.rezaiefar@yahoo.com</a>> wrote:</div><br class="Apple-interchange-newline"></blockquote><blockquote type="cite" class=""><div dir="auto" class=""><div class=""><div class=""><div class=""><div id="yui_3_16_0_1_1449450934881_6934" dir="ltr" class=""><font class=""><span style="background-color: rgba(255, 255, 255, 0);" class="">Hello every one,</span></font></div></div></div></div></div></blockquote><br class=""><blockquote type="cite" class=""><div dir="auto" class=""><span style="background-color: rgba(255, 255, 255, 0);" class="">I am wondering if ndn does not use any information of users for sending Interest message, how this network deliver data to the user. </span><span style="background-color: rgba(255, 255, 255, 0);" class="">Moreover, I would like to say that the Data message is passed the reverse path that interest message is received and each router saves the interface from where it receives this interest message. any how, if more than one user is connected to one interface ( for example in wireless network), the router broadcasts data message to all of them? if this can be happened, how they can control behavior of user and block the malicious user ?</span></div></blockquote><blockquote type="cite" class=""><div dir="auto" class=""><span style="background-color: rgba(255, 255, 255, 0);" class="">Any help will be appreciated </span><br class=""><span style="background-color: rgba(255, 255, 255, 0);" class="">thanks in advance</span><br class=""><div class=""><div class=""><div class=""><div id="yui_3_16_0_1_1449450934881_7040" dir="ltr" class=""><font class=""><span style="background-color: rgba(255, 255, 255, 0);" class="">best regards</span></font></div></div></div></div></div></blockquote><br class=""></div><div>Hi Zeinab,</div><div><br class=""></div><div>I don't have a single answer to your question. NFD support multiple modes of the forwarding data back, depending on how exactly users deliver interest packets to the router. Specifically, which face has been used: if interest was sent/received using multicast face, then the data packet is multicasted back too. If individual users send interest packets using unicast faces (e.g., UdpFace), then answer is unicasted to each requester. We also have in works modification to the multicast face, which would optionally allow unicasting of data packets (by recording and then using lower layer addressing). This could also include the option to ignore specific senders (or whitelist specific senders), though this may not be a very reliable mechanism.</div><div><br class=""></div><div>The default behavior in ndnSIM to use NetDeviceFace, which effectively is a multicast face. If in your simulation scenario you're using wireless network, then the response is multicasted/broadcasted.</div><div><br class=""></div><div>---</div><div>Alex</div><div><br class=""></div></body></html>