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What is the maximum number of hops from the device that generated the given output to its BGP neighbor at 4.4.

What is the maximum number of hops from the device that generated the given output
to its BGP neighbor at 4.4.4.4?
Refer to the exhibit.

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A.
3

B.
252

C.
5

D.
255

E.
2

F.
254

Explanation:
same as example:
https://supportforums.cisco.com/document/86776/securing-ebgp-sessions-ttl-securityfeature
the missing part from output is (so that is the answer)
External BGP neighbor may be up to 3 hops away.
command applied on that appliance is:
neighbor 4.4.4.4 ttl-security hops 3This feature is configured using neighbor <ip-address> ttl-security hops <count> BGP
configuration command. The TTL value is calculated by the router from the configured
hop count i.e. TTL = 255 – (hop count).
This feature has few limitations
On enabling neighbor ttl-security feature, neighbor ebgp-multihop is not required.
The feature is only for EBGP and not IBGP.
4.4.4.4 is originating BGP packets with a TTL of 255, and R expects the packets it receives from 4.4.4.4 to have at least 252 (as in BGP configuration of R has neighbor
4.4.4.4 ttl-security hops 3, so a TTL value 255-3=252).
The BGP will establish and maintain the session only if the TTL value in the IP packet is
equal to or greater than the TTL value configured for the peer.


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