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RE: Does TTL just decrease at routers [7:131907] posted 07/12/2008
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>From a PACKET standpoint, does a switch count?

The short answer is at Layer 2, no, the TTL does not decrease at each
switch.  TTL decreases at routing points (as it's an IP field, the PACKET is
hit, switches deal in FRAMES).

If you are doing L3 switches, all bets are off.  :)


Scott Morris, CCIE4 #4713, JNCIE-M #153, JNCIS-ER, CISSP, et al.
Senior CCIE Instructor



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-----Original Message-----
From: nobody@xxxxxxxxxxxxxx [mailto:nobody@xxxxxxxxxxxxxx] On Behalf Of
Xiaobo Zhu
Sent: Friday, July 11, 2008 11:46 PM
To: cisco@xxxxxxxxxxxxxx
Subject: Does TTL just decrease at routers [7:131907]

I just want to know if TTL decrease on other devices, switches for example,
or it only decrease when pass a router?
Many thanks!

cheers, Xiaobo

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