Feature #4973
Updated by Davide Pesavento almost 4 years ago
The current self-learning implementation of #4279 allows NFDs to learn FIB entries through Prefix Announcement piggybacked on Data replying to discovery Interest. The learned next hop is where Data sent back, so the next hop will be a multicast Face by default. We tested the performance of UDP multicast and unicast Face in WiFi AP-station mode. The testing topology consisted of two laptops connecting to one Openwrt router. NDN router.NDN catchunks and putchunks were used to download and publish data. The goodput of unicast is about **5x** as good as the multicast. The detailed statistics is listed in the end. Therefore, the multicast/Unicast face switching is important. To implement Face switching, our existing effort was to extend the concept of *Face* to *FaceEndpoint* (Face+EndpointId). [*Face-EndpointId*](#4282). This approach would add will leave *EndpointId* in table, management, management and forwarder modules, but these modules in NDN should not deal with *EndpointId*. To avoid Face extension with EndpointId, this design allows the forwarding strategy to create a unicast face Face on receiving Data packet from a multicast face. Face. More specifically, strategy can use `face->channel->connect()` **face->channel->connect** to create a new face. ## NDN catchunks/putchunks catchunks/putchanks for consumer---WiFi AP---producer ### Unicast: All segments have been received. Time elapsed: 6.83123 seconds Segments received: 1317 Transferred size: 1447.75 kB Goodput: 1.695452 Mbit/s Congestion marks: 0 (caused 0 window decreases) Timeouts: 23 (caused 16 window decreases) Retransmitted segments: 23 (1.71642%), skipped: 0 RTT min/avg/max = 8.058/71.200/421.579 ms ### Multicast: All segments have been received. Time elapsed: 33.6946 seconds Segments received: 1317 Transferred size: 1447.75 kB Goodput: 343.734634 kbit/s Congestion marks: 0 (caused 0 window decreases) Timeouts: 553 (caused 191 window decreases) Retransmitted segments: 550 (29.459%), skipped: 3 RTT min/avg/max = 16.970/88.583/333.864 ms