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New Member

Max. # of hops

TTL is 8-bit, but this does not mean that the IP packet goes from source to destination by 255 hops. Thus, what is the max. # of hops that the IP packet traverse from the source to the destination.

Remeber that a packet goes from source to destination passing through all types of routers and protocols.

if you support your answer with a reference, that would be great.

Many thanks

Dr. Abdullah


Re: Max. # of hops

No, it means the life time of a packet is 255 hops, everytime a packet traverses a router the TTL will be decremented by 1. This stops packets that are stuck in a routing loop endlessly bouncing around and taking up resources.

The end station or source will set the TTL.

Routing Protocols have there defination of HOP count not TTL, which is from source of that router to a destination, this does not equate to TTL in the IP header.

New Member

Re: Max. # of hops


This thread refreshes my memory that my client asking why he would get a TTL value of large range when pinging different devices on his LAN - say routers and PC's normally being larger(2XX) but voice gateways being much smaller (XX), so can I say TTL value is specifically determined by the device itself(the firmware inside?) and the protocol o(TCP/IP ?) will modifiy packets with such information..

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