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Which device in a LISP router architecture receives LISP Map-Requests and determines which ETR should process the Map-Request?

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D
100% (3)
A
0% (0)
B
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C
0% (0)
Discussion · 5
16
Given answer is correct! When MS and MR function runs on separate devices: 1. ITR --'map-request'--> MAP-Resolver (MR) 2. MR --- forwards 'map-request' -----> MAP-Server (MS) 3. MS --- checks DB for RLOC -- finds (ETR) 4. MS -- Sends 'map-request' to ------> Egress Tunnel Router (ETR) 5. ETR -- sends 'MAP-Reply' directly to ----->ITR When MS and MR function runs on same devices (which is this question): 1. ITR --'map-request'--> MAP-Resolver (MR/MS) 2. MS --- checks DB for RLOC -- find (ETR) 3. MS -- Sends 'map-request' to ------> Egress Tunnel Router (ETR) 4. ETR -- sends 'MAP-Reply' directly to ----->ITR https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/iproute_lisp/configuration/15-mt/irl-15-mt-book/irl-overview.pdf
2
the best explanation ive ever seen on this website many thanks
1
It's confusing. Because either way MR gets requests, but MS finds ETR and the question asks for both functions at the same time. So which one?
D 1
Selected Answer: D I would pick D, since map server receives map-requests from map resolver and looks up EID-RLOC mapping in its database.
D 1
Selected Answer: D Map server (MS): An MS sets LISP site policy to authenticate when LISP sites try to register to the MS. It also does the following: Provides a service interface to the ALT router and injects routes in the ALT BGP when the site registers. Receives MAP requests over the ALT router and encapsulates them to registered ETRs. Map resolver (MR): The MR does the following: Receives MAP requests, which are encapsulated by ITRs. Provides a service interface to the ALT router, de-encapsulates MAP requests, and forwards on the ALT topology. Sends negative MAP replies in response to MAP requests for non-LISP sites.