# Aloha ## Setup ![](https://i.imgur.com/pxg2W0S.png) ### Network stats | PING SWITCH *(ms)* | Avg | Min | Max | mDev | | -------- | -------- | -------- | -------- | -------- | | P2P b2b | 0.117 | 0.102 | 0.165 | 0.010 | | MITM b12m | 0.499 | 0.346 | 1.066 | 0.118 | | MITM b22m | 0.472 | 0.309 | 1.452 | 0.081 | ### NTP Timesyncd (board) + ntpd server (MITM). Boards sync only with the MITM every 16-30 seconds. ### MITM UDP Server, .NET 5, simple forwarding. Also simulates gaussian delay and packet loss asyncrhonously. ### TCPDump Using `taskset` on the boards to run tcpdump on an isolated core, to avoid latency spikes. TCPdump reads only 50 bytes (out of ~900), since we only need the packet timestamp. Running TCPdump on each device allows us to measure the single-hop **directional** latency of the network. We use the timestamp field of the rtp packet to determine the packet ID, while using the tcpdump date to track its time-flow. ## Results ### P2P NTP vs no-NTP <details> <summary>Delay Scatter</summary> ![](https://i.imgur.com/IR5RF61.png) </details> <details> <summary>Delay Histogram</summary> ![](https://i.imgur.com/vUhmOnr.png) </details> <details> <summary>Packet Loss</summary> ![](https://i.imgur.com/6Kg8SPe.png) </details> <details> <summary>Packet Delta Time</summary> ![](https://i.imgur.com/eYXvFlW.png) </details> ### MITM nodelay #### MITM dump <details> <summary>Delay Scatter</summary> ![](https://i.imgur.com/5PF0YnW.png) </details> <details> <summary>Delay Histogram</summary> ![](https://i.imgur.com/O0OSef6.png) </details> <details> <summary>Packet Loss</summary> ![](https://i.imgur.com/Mmg0TlE.png) </details> <details> <summary>Packet Delta Time</summary> ![](https://i.imgur.com/md1KvyV.png) </details> #### BOARDS dump <details> <summary>Delay Scatter</summary> ![](https://i.imgur.com/TE4msXM.png) </details> <details> <summary>Delay Histogram</summary> ![](https://i.imgur.com/CptYERs.png) </details> <details> <summary>Packet Loss</summary> ![](https://i.imgur.com/URfM4LE.png) </details> <details> <summary>Packet Delta Time</summary> ![](https://i.imgur.com/ILV1hUz.png) </details> ### MITM delay + loss #### MITM dump <details> <summary>Delay Scatter</summary> ![](https://i.imgur.com/GqigE5P.png) </details> <details> <summary>Delay Histogram</summary> ![](https://i.imgur.com/f5bZnmS.png) </details> <details> <summary>Packet Loss</summary> ![](https://i.imgur.com/VMDa8KW.png) </details> <details> <summary>Packet Delta Time</summary> ![](https://i.imgur.com/hHneF3I.png) </details> #### BOARDS dump <details> <summary>Delay Scatter</summary> ![](https://i.imgur.com/Fef3F7r.png) </details> <details> <summary>Delay Histogram</summary> ![](https://i.imgur.com/R52VHDT.png) </details> <details> <summary>Packet Loss</summary> ![](https://i.imgur.com/Tr4fCda.png) </details> <details> <summary>Packet Delta Time</summary> ![](https://i.imgur.com/kgYnjkA.png) </details> ### MITM nodelay wifi #### MITM dump <details> <summary>Delay Scatter</summary> ![](https://i.imgur.com/WXyobRD.png) </details> <details> <summary>Delay Histogram</summary> ![](https://i.imgur.com/7yZjXvr.png) </details> <details> <summary>Packet Loss</summary> ![](https://i.imgur.com/kwtRAoU.png) </details> <details> <summary>Packet Delta Time</summary> ![](https://i.imgur.com/9AGf4Ub.png) </details> #### BOARDS dump <details> <summary>Delay Scatter</summary> ![](https://i.imgur.com/GFWZq0O.png) </details> <details> <summary>Delay Histogram</summary> ![](https://i.imgur.com/J0laNSd.png) </details> <details> <summary>Packet Loss</summary> ![](https://i.imgur.com/39yld0B.png) </details> <details> <summary>Packet Delta Time</summary> ![](https://i.imgur.com/RCQS7R0.png) </details>