JN0-650 Dumps with Practice Exam Questions Answers

EVPN Route Type 5 (IP Prefix Route) is used to advertise IP prefixes (subnets) between broadcast domains or between VRFs in an EVPN fabric.

IP-VRF-to-IP-VRF (Statement C): In an EVPN-VXLAN architecture, Type 5 routes are primarily used for Layer 3 connectivity. They allow different IP-VRFs on different VTEPs to exchange prefix information directly. This model is widely referred to as IP-VRF-to-IP-VRF routing because it enables inter-subnet routing at the leaf layer without requiring Layer 2 MAC learning for those specific prefixes.

Overlay Next Hop (Statement B): For a PE router to reach a prefix advertised via a Type 5 route, it must resolve the overlay next hop. This next hop is typically the loopback IP address of the originating VTEP, which the receiving router uses to build the VXLAN tunnel.

Why others are incorrect: Statement A is incorrect because Type 7 routes are used for IGMP/MLD join synchronization. Statement D is incorrect because Type 5 routes advertise IP prefixes, not MAC addresses; MAC extended communities are associated with Type 2 routes.

OSPF (Open Shortest Path First) is a standards-based Link-State Interior Gateway Protocol (IGP) implemented within Junos OS 24.4:

Intra-AS Routing: OSPF is designed to distribute routing information and perform neighbor discovery within a single Autonomous System (AS). It divides the AS into areas to localize Link-State Advertisements (LSAs) and reduce the size of the Link-State Database (LSDB) on each router. (Option B)

Algorithm: OSPF uses the Shortest Path First (SPF) or Dijkstra algorithm, not a distance vector algorithm (which would be RIP or BGP). This makes Option A incorrect.

Directly Connected Routes: In Junos OS, you must explicitly configure an interface under the [edit protocols ospf] hierarchy to include it in the OSPF process. Once an interface is added, its prefix is automatically advertised to neighbors via Router (Type 1) LSAs. This makes Option C technically inaccurate in the context of interfaces participating in the protocol.

Scope: Protocols used between multiple autonomous systems are External Gateway Protocols (EGPs), such as BGP. This makes Option D incorrect.

This question focuses on port security and preventing " rogue switches " or multiple devices from accessing a single physical port simultaneously.

Single-Secure Supplicant Mode (Option A): This is the most restrictive 802.1X mode in Junos OS. It allows exactly one MAC address to be authenticated on the port at a time. If a device successfully authenticates, the switch will drop any traffic coming from any other MAC address on that same physical interface. If a user tries to plug in a switch, only the first device that authenticates will have access; all other devices behind that switch will be blocked.

Single Supplicant Mode (Option C): This mode allows the first authenticated user to " open " the port for all other users. This would actually allow a rogue switch to function once the first device is authorized.

Multiple Supplicant Mode (Option B): This allows multiple devices to connect, provided each one authenticates individually. While secure, it does not prevent a user from connecting multiple devices to the port, which violates the requirement to allow only one.

MAC-RADIUS (Option D): This is an authentication method, not a port-access mode that limits the number of supplicants.

In this scenario, the requirement is to authenticate devices based on their MAC addresses using a centralized database.

MAC RADIUS (Option A): This is the standard Juniper method for authenticating " headless " or non-802.1X capable devices based on their hardware (MAC) address. The switch acts as a proxy, sending the device ' s MAC address as the username and password to a centralized RADIUS server (the centralized database). If the MAC address is found in the server ' s database, the device is granted access to the network. This perfectly matches the user ' s requirement for MAC-based authentication and a centralized database.

Captive Portal (Option B): This is a web-based authentication method requiring user interaction (login via a browser), which is not based on MAC address identification for the initial authentication phase.

Supplicant Modes (Options C & D): These define how multiple devices are handled on an 802.1X-enabled port, but they are not authentication methods themselves; they rely on 802.1X (EAP-based) or MAC-RADIUS being already configured.

OSPFv2 (IPv4) and OSPFv3 (IPv6) share many fundamental concepts, such as the SPF algorithm and the use of areas, but they have distinct differences in how they handle prefix information and LSA headers in Junos OS.

Backbone Requirement (Option C): Both OSPFv2 and OSPFv3 utilize a hierarchical structure. In both versions, all areas must connect to a central Area 0 (the backbone) to allow for inter-area routing. If an area is not physically connected to Area 0, a virtual link must be established.

Flooding Scope (Option D): One of the significant architectural changes in OSPFv3 is the inclusion of the flooding scope directly into the LSA header. In OSPFv3, the LS Type field is expanded to 16 bits, where the top three bits define the flooding scope (e.g., Link-local, Area, or AS scope). This allows routers to understand how far an LSA should be propagated without needing to understand the specific LSA type itself.

LSA Prefix Information (Option A): This statement is misleading. In OSPFv2, Router and Network LSAs (Type 1 and 2) carry both topology and prefix information. However, a key design goal of OSPFv3 was to separate topology from prefix information. In OSPFv3, Type 1 and 2 LSAs only describe the topology, while prefixes are carried in new LSA types: Intra-Area-Prefix-LSAs (Type 9) and Link-LSAs (Type 8).

Processing (Option B): OSPFv2 is processed " per-subnet " because it forms adjacencies based on IPv4 subnets. OSPFv3 is processed " per-link " , meaning it forms adjacencies between interfaces on the same physical link regardless of whether they share a common IPv6 prefix.