the double arrow means you activated/selected the turbo mode with this plane. 1)
grey arrows means: out of multiplayer range, there is the simple grey arrow and double grey arrow (out of multiplayer range , but selected for turbo)
blue arrows means: in multiplayer range but no P2P detected/established, there is a simple blue arrow, and the double blue arrow (with turbo selected but no way to happen since no P2P). Most non FSInn pilot will appear grey or blue, some FSInn users will appear blue if they disabled P2P.
green arrows means: in multiplayer range with P2P activated/established. if a pilot is green you are at least in 1 or 2Hz. double arrow means you selected this plan for turbo, if after clicking turbo the double arrow stays blue, it means the remote user limited his P2P settings to 1 or 2Hz
yellow arrow, only double arrow mean: in multiplayer range and P2P activated in turbo above 2Hz. This mean you are in perfect conditions for formation flights.
there you will see stats on all network traffic when connected to FSD server you will see at least one entry in inbound and outbound.
Fields means:
Info : FSDNetX or the callsign of P2P pilots
Hz : Hertz (not the car rent), times per second, frequencies of position updates, doesnt apply to FSD connection
Kbps : kilobits per seconds, the REAL network traffic in UDP or TCP for this connection, divide it by 8 to make KB/secs or Ko/secs.
RTT: Round Time Trip, the time to make the trip to the remote and back trip. Divide it by 2 to get an overview on network latency, in millisecs
PLps : Packet Lost per seconds, amount of UDP packet lost per second, if you have frequently PLps, ohh by, you are in troubles. doesnt apply to FSD connections
IP: can be AA.BB.... or (R)AA.BB... or LAN , it gives tips about remote ip, LAN means we detected the remote pilot on LAN, we dont need to get to internet to send position updates (usually RTT will be below 10ms) in that case, AA.BB... is the public IP address, if there is a (R) in front that means that the connection is Resolved, because of your provider, NAT router etc ... in case of (R) we use special tech to reach peers, kind of complex to explain here, RTT will be a bit longer in that case, but it should work flawless.
1)
reminder: default P2P mode in FSInn is 2Hz (2 times per second, every 500millisecs), going in turbo will negociate the best frequency possible between your config and the config in remote plane and the turbo frequency can go to 80Hz ( 80 position updates per second , every 12.5 millisecs).