* used to provide an upper bound to this doubling operation.
*
* Special Case: the first HB doesn't trigger exponential backoff.
- * The first unacknowleged HB triggers it. We do this with a flag
+ * The first unacknowledged HB triggers it. We do this with a flag
* that indicates that we have an outstanding HB.
*/
if (!is_hb || transport->hb_sent) {