At 15:14 17/03/2001 -0700, Vernon Schryver wrote:
] That's my reason to use the TTL decrement; if someone shows me a device
] where a packet comes in on one interface with a certain TTL, and it comes
] out on another interface with a lower TTL but no other significant changes,
] I call it a router.
] If it is incapable of not doing other significant damage, I call it an
] application layer gateway, a NAT box, or something else, but not a router.
What about the changes to the IP header required to deal with an
IP record-route option?
if it's incapable of dealing with a datagram that does not have a
record-route option, it is indeed a strange beast :-)
There seem to be three types of routers:
1. those that deal with LSRR and RR options correctly
2. those that mess them up, including generating pure garbage IP packets
3. those that ignore them.
As far as I can tell, Type 1 and Type 2 are each more common than Type 3.
the field of Internet-connected boxes can be divided into 3 types of devices:
- Correctly functioning routers (conforming to full RFC 1812 and friends)
- Buggy routers (including your cat 2 and 3 above)
Some people surmise that the first category is empty....
note: I have not yet found anything that allows me to tell the difference
between a switch and something that is not a switch. That is one reason why
I prefer to avoid the term.
metanote: the field of categorizations can be divided into two categories:
- those that are useful
- those that are useless
the last category is demonstrably larger than the first.....
metametanote: the categorization above may be a member of its second category.
Harald Tveit Alvestrand, alvestrand(_at_)cisco(_dot_)com
+47 41 44 29 94
Personal email: Harald(_at_)Alvestrand(_dot_)no