+STATIC_ASSERT (STRUCT_OFFSET_OF (transport_connection_t, s_index)
+ == TRANSPORT_CONN_ID_LEN, "update conn id len");
+
+/* Warn if size changes. Two cache lines is already generous, hopefully we
+ * won't have to outgrow that. */
+STATIC_ASSERT (sizeof (transport_connection_t) <= 128,
+ "moved into 3rd cache line");
+
+#define foreach_transport_proto \
+ _(TCP, "tcp", "T") \
+ _(UDP, "udp", "U") \
+ _(NONE, "ct", "C") \
+ _(TLS, "tls", "J") \
+ _(UDPC, "udpc", "U") \
+ _(QUIC, "quic", "Q") \
+