-// This function tries to establish a tunnel to a node (or its relay) so that packets can be sent (e.g. get SPTPS keys).
-// If a tunnel is already established, it tries to improve it (e.g. by trying to establish a UDP tunnel instead of TCP).
-// This function makes no guarantees - it is up to the caller to check the node's state to figure out if TCP and/or UDP is usable.
-// By calling this function repeatedly, the tunnel is gradually improved until we hit the wall imposed by the underlying network environment.
-// It is recommended to call this function every time a packet is sent (or intended to be sent) to a node,
-// so that the tunnel keeps improving as packets flow, and then gracefully downgrades itself as it goes idle.
-static void try_tx(node_t *n) {
+/* These functions try to establish a tunnel to a node (or its relay) so that
+ packets can be sent (e.g. exchange keys).
+ If a tunnel is already established, it tries to improve it (e.g. by trying
+ to establish a UDP tunnel instead of TCP). This function makes no
+ guarantees - it is up to the caller to check the node's state to figure out
+ if TCP and/or UDP is usable. By calling this function repeatedly, the
+ tunnel is gradually improved until we hit the wall imposed by the underlying
+ network environment. It is recommended to call this function every time a
+ packet is sent (or intended to be sent) to a node, so that the tunnel keeps
+ improving as packets flow, and then gracefully downgrades itself as it goes
+ idle.
+*/
+
+static void try_tx_sptps(node_t *n) {