TTL - ShadowJonathan/ByteCart GitHub Wiki

TTL means "Time to live". It is a common term in networks.

The TTL is a counter attached to each ticket initialized to a high value (64, default value in configuration file) and decremented each time the cart crosses a router or exits a subtrack. If the cart is taken in a loop, the counter will eventually reach zero and the cart (or train) will be routed to garbage collector or will be returned to sender (if a return address was previously stored using BC7015 sign).

TTL is stored in tickets.

Since TTL initial value gives the maximum cumulative duration of a trip, players must take care to not reuse the same ticket.

If a the busy line of a station is lit, carts going to that station can run in infinite loop and the TTL may expire. For this reason, stations using the busy line must not hold it too much time.