add network test feature (PING/PONG with latency stats)

New frame types PING (0x0B) and PONG (0x0C), each carrying an 8-byte nonce. Server echoes PING nonce verbatim in PONG. Client sends pings at random 10-100ms intervals, correlates nonces to measure RTT. Stats shown live: sent/recv counts, loss %, average latency, jitter (mean absolute delta of consecutive RTTs). Test button toggles on/off. Updated both Rust server (echo in main.rs) and C# client (PingTest.cs, SessionManager routing, MainForm Test button + stats label).
2026-08-13 08:28:59 +00:00
parent a2d3643d69
commit 279af33fd8
7 changed files with 242 additions and 4 deletions
@@ -46,6 +46,8 @@ emitted in v1.
 | 0x05 | OPEN_NAK    | S → C         | 0          | `upstream_id:1, reason:1`        |
 | 0x06 | DATA        | both          | session    | raw bytes (≤1480)                |
 | 0x07 | CLOSE       | both          | session    | optional `reason:1`              |
+| 0x0B | PING        | C → S         | 0          | `nonce:8`                        |
+| 0x0C | PONG        | S → C         | 0          | `nonce:8` (echoed)               |

 Reserved (unimplemented in v1; parse returns Err, encode unimplemented):

@@ -140,6 +142,18 @@ field identifies which session the bytes belong to.

 - **reason** (u8, optional): present iff payload length ≥ 1. See reason codes.

+### PING / PONG payload
+
+```
+                                                               +
+| nonce (big-endian, 8 bytes)                                   |
+                                                               +
+```
+
+- **nonce** (u64, big-endian): arbitrary value chosen by the client. The
+  server echoes it verbatim in the PONG reply. Used to correlate RTT
+  measurements.
+
 ## Reason codes

 | Value | Meaning           |