SID_UDPPINGRESPONSE
| Protocol | BNCS |
|---|---|
| Directions | Client → Server |
| Used by |       
|
Tells the server the UDP test worked, by echoing the code the server sent over UDP.
Client → Server
After the client receives PKT_SERVERPING over UDP, and before SID_ENTERCHAT.
| Type | Field | Notes | Confidence |
|---|---|---|---|
UINT32 |
UDP code | The value from PKT_SERVERPING. Official servers used bnet. |
✅ Verified |
Remarks
If the client never sends this, the server marks the user with the No UDP flag (0x10), which other players see as a plug icon, and the client can't create or join games.
Timing matters on official servers. Sending this before the version check starts, or after entering chat, got clients disconnected.
Diablo is unresolved. BNETDocs lists Diablo among the games that send this message. It also records that official Battle.net always showed Diablo users with the No UDP flag regardless. This hasn't been confirmed with a real Diablo client.
Appears in
Sources and credits
- BNETDocs Atlas server (MIT): message handler used to cross-check the layout
- Command Center: bnetccd session handling: older logon tested with a real Warcraft II client
- BNETDocs, SID_UDPPINGRESPONSE (client to server): documented by the original BNETDocs contributors.
This page is written in our own words. BNETDocs is credited for its research; none of its text is copied. See Credits.