350-501 Services Practice Question
A service provider is deploying LISP (Locator/ID Separation Protocol) to provide mobility and multihoming for customer endpoints. Which LISP component is responsible for maintaining the mapping between Endpoint Identifiers (EIDs) and Routing Locators (RLOCs) and for responding to Map-Request messages from ITRs?
⚠ Common exam trap
Cisco often tests the distinction between the Map-Server and Map-Resolver, where candidates confuse the Map-Resolver's role of forwarding requests with the Map-Server's role of maintaining the authoritative mapping database and responding to Map-Requests.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Map-Server (MS)
The Map-Server (MS) is the central control-plane component in LISP that maintains the authoritative mapping database of EID-to-RLOC entries. When an Ingress Tunnel Router (ITR) sends a Map-Request for an unknown EID, the Map-Server receives it, looks up the mapping, and either responds directly or forwards the request to the appropriate Egress Tunnel Router (ETR) for a reply. This makes the MS the correct answer for maintaining mappings and responding to Map-Requests.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Ingress Tunnel Router (ITR)
Why it's wrong here
ITR encapsulates packets and sends Map-Requests, but does not maintain the mapping.
- ✓
Map-Server (MS)
Why this is correct
MS maintains the EID-to-RLOC mapping and responds to Map-Requests.
- ✗
Map-Resolver (MR)
Why it's wrong here
MR forwards Map-Requests to the MS; it does not hold mappings.
- ✗
Egress Tunnel Router (ETR)
Why it's wrong here
ETR decapsulates packets and registers EID prefixes with the MS.
Go deeper
Related to this question
About these practice questions
One of 971 original 350-501 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This 350-501 practice question is part of Courseiva's free Cisco certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 350-501 exam.