Exam 350-401 All QuestionsBrowse all questions from this exam
Question 916

Which device, in a LISP router architecture, receives LISP map requests and determines which ETR should handle the map request?

    Correct Answer: C

    In the LISP (Locator/ID Separation Protocol) router architecture, the device responsible for receiving LISP map requests and determining which Egress Tunnel Router (ETR) should handle the map request is the map resolver (MR). The map resolver takes the incoming map requests from the Ingress Tunnel Router (ITR) and forwards them to the appropriate map server (MS), which then consults its database to find the correct ETR. Once identified, the map server sends the map request to the ETR, which then replies back to the original ITR.

Discussion
nj1999Option: C

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 --- check 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 --- check 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

pancadapy

the best explanation ive ever seen on this website many thanks

SeMo0o0oOption: C

C is correct

andriuka

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?