Does TTL mean I can't make a request farther than 255 hops away?

Question

I have come to understand how TTL works partially. Quoting Wikipedia

The TTL field is set by the sender of the datagram, and reduced by every router > on the route to its destination.

and

The maximum TTL value is 255, the maximum value of a single octet

Basing on these statement, I would assume all requests will be dropped if I am more than 255 hopes away in any configuration. Is there an exception I am missing? Or is there a rule that says you can not be farther than 225 away?

EDIT

And what is the advantage of limiting the TTL to 64 or lower. I see some OSs do that.

Answer 1

That would be true. Most OSes have default TTL set at half or a quarter of that. You should understand that you can send an IP packet around the world several times before you would reach the 255 hop limit.

The real use for the hop limit is to mitigate the damage due to routing loops.The advantage of limiting the TTL would be to recover from paralysis due to a routing loop faster. You can really reach anywhere in around 20 hops. By having a TTL of 64, a large transfer which hit a routing loop would be over in a quarter of the time that a TTL of 255 would take to recover. It's difficult to diagnose and correct such a problem when the routers are swamped by traffic in the loop. Switches use frames, which don't have anything like TTL in the frames, and you can completely kill a network indefinitely with an unchecked broadcast storm.