Test Request Message Fields
| Tag | Field Name | Required | Description |
|---|---|---|---|
| 35 | MsgType | Y | 1 |
| 112 | TestReqID | Y | Auto-generated request ID. |
If a HearbeatInterval + 1 seconds have elapsed since the last message received, a Test Request message should be issued. If another HearbeatInterval + 1 seconds elapse without receiving a message, the TCP connection should be dropped. This ensures that a broken TCP connection will be detected even if the TCP stack doesn’t notice (this has been observed to happen in WAN environments, particularly when a VPN is involved).