Juniper Networks Certified Internet Associate docx

Exam : JN0-201 Title : Juniper Networks Certified Internet Associate Ver : 09.21.2006 JN0-201 Actualtests.com - The Power of Knowing QUESTION 1 Which two statements are true concerning the JUNOS software? (Choose two.) A. Processes are tightly integrated with each other. B. Processes are fully independent from each other. C. Processes run in a protected memory environment. D. Processes may fail and cause a failure of the entire system. Answer: B, C Explanation: From Juniper.com, Benefits of the JUNOS operating system: Each user process runs in its own protected memory space. This ensures that the failure of one subsystem will not negatively impact the operation of other subsystems executing over the operating system. QUESTION 2 Which boot device contains the primary copy of the JUNOS software? A. hard drive B. floppy drive C. PCMCIA flash D. internal flash drive Answer: D Explanation: The router stores bootable copies of the JUNOS software in three possible locations: the internal flash disk, the hard drive, or the removable media. The primary boot location is the internal flash disk. The hard drive is the secondary boot location, while the removable media is used for disaster-recovery purposes. QUESTION 3 Which path will a packet follow within a Juniper Networks router after it enters an interface and before a forwarding table lookup is performed? A. PIC I/O Manager, Buffer Manager, I/O Manager, Internet Processor B. PIC I/O Manager, Buffer Manager, Internet Processor, I/O Manager C. PIC I/O Manager, I/O Manager, Buffer Manager, Internet Processor D. PIC I/O Manager, I/O Manager, Internet Processor, Buffer Manager Answer: C Explanation: When a data packet arrives on an interface, the PIC I/O Manager performs error-checking, then transmits the packet to the I/O Manager. The I/O Manager removes the layer 2 header and segments the packet into 64-byte J-cells. It then sends those J-cells to the Inbound Distributed Buffer Manager. The Buffer Manager then sends a notification cell to the Internet Processor, which performs a forwarding table lookup. JN0-201 Actualtests.com - The Power of Knowing QUESTION 4 Given the following configuration: interfaces { so-0/0/0 { unit 0 { family inet { address 10.10.10.1/24; } } } so-0/0/1 { unit 0 family inet { address 20.20.20.1/24; } } } lo0 { unit 0 { family inet { address 192.168.1.1/32; } } } } Which is considered an exception packet? A. IP packet addressed to 10.100.100.10 B. IP packet with the Router Alert option set C. ICMP traceroute packet with TTL set to 5 D. ICMP echo request addressed to 172.16.1.1 Answer: B Explanation: The PFE can't process some data packets in its normal fashion. These packets are referred to as exception packets. Examples of exception packets are: Routing protocol updates, Packets addressed to the router, Packets requiring generation of ICMP error messages, or Packets containing an IP Options field. Answer B is correct because an IP Option field is set in the packet. A,C, and D are all examples of packets that are be forwarded through the router as none of them are destined for the router or require special attention. QUESTION 5 From within the [edit] portion of the configuration, which command restores the JN0-201 Actualtests.com - The Power of Knowing number 2 rollback file? A. rollback 2 B. run rollback 2 C. request system rollback 2 D. run request system rollback 2 Answer: A Explanation: The JUNOS software saves up to nine previous configuration files. The most recent config file is called juniper.conf.1.gz and is number 1. The naming convention continues with each older file incrementing by 1. You restore a config file with the rollback command and the number of the config file to restore. Rollback is a configuration mode command not an operation mode command, so within [edit] it is not necessary to precede the command with the command "run". QUESTION 6 A network administrator would like to verify the active alarms on the interface so-0/0/0.0. Which command displays this information? A. show alarms B. show interfaces terse C. show alarms extensive D. show interfaces extensive Answer: D Explanation: The "show interfaces extensive" command displays all possible information about every interface including active alarms and any error conditions. QUESTION 7 Which ASIC is responsible for segmenting a packet into 64-byte J-Cells? A. PIC I/O ASIC B. I/O Manager ASIC C. Buffer Manager ASIC D. Internet Processor ASIC Answer: B Explanation: The I/O Manager ASIC removes the layer 2 header and segments the packet into 64-byte J-cells. QUESTION 8 During the boot sequence of the JUNOS software, which device is consulted first, by default? JN0-201 Actualtests.com - The Power of Knowing A. hard drive B. LAN server C. removable media D. internal flash drive Answer: C Explanation: The removable media is the first boot location examined. If the router finds a copy of the JUNOS software there, it loads the software on the router. This presents a possible hazard in your network since all existing files and file systems on the router are erased during this process. This type of boot process returns the router to a factory default-type environment and should be used only for disaster recovery. If no removable media is present, the router loads the software from the internal flash disk. This is considered the normal boot operation and should occur at each router start. QUESTION 9 Which protocol family is required prior to assigning an IP address to an interface? A. family ip B. family ip6 C. family inet D. family inet4 Answer: C Explanation: Each logical interface in the JUNOS software has the ability to support one or more protocol families. The inet protocol family supports IP version 4 (IPv4) packets. QUESTION 10 The monitor traffic command closely resembles that UNIX based utility? A. ps -x B. passwd C. ls -a-l D. tcpdump Answer: D Explanation: The "monitor traffic" command prints packet headers to your terminal screen for information sent or receive by the routing engine. It is very similar in operation to the Unix tcpdump utility. QUESTION 11 Which command ensures that a configuration file on a backup Routing Engine is identical to the file on the primary Routing Engine? JN0-201 Actualtests.com - The Power of Knowing A. commit check B. commit and-quit C. commit confirmed D. commit synchronize Answer: A Explanation: One of the options for the "commit" command is "synchronize". When you have a router with two routing engines installed, this option tells the router to apply the candidate configuration to both routing engines. QUESTION 12 If there is a BGP next hop with equal preference in inet.0 and inet.3, which version of the route will BGP use? A. the route in inet.3 B. the route in inet.0 C. the route with the lower metric D. It will randomly choose between inet.0 and inet.3. Answer: A Explanation: The inet.0 routing table is used to store IPv4 routes. All routing protocols place information into this table by default. The inet.3 routing table contains the egress IP address of a MPLS lable switched path (LSP). Routes are inserted into inet.3 by the RSVP protocol. In the case of a preference tie between the routing tables, the JUNOS software prefers the inet.3 table and the LSP. QUESTION 13 When a router receives a label of zero it will ____. A. perform a label pop B. perform a label swap C. perform a label push D. send an error message toward the ingress router Answer: A Explanation: Popping the MPLS Label Our definition of each router's role along the path of an LSP assumes the default JUNOS software behavior of penultimate hop popping (PHP). In this case, the penultimate transit router in the LSP performs the label pop operation. Another option exists for popping the MPLS from the data packet- ultimate hop popping. Ultimate hop popping occurs when the egress router itself performs the pop operation. This requires the egress router to perform two operations on the data packet: the pop and JN0-201 Actualtests.com - The Power of Knowing an IPv4 lookup to forward the packet. This dual operation places a larger processing burden on the egress router, which prompts the use of PHP. The technical difference between PHP and ultimate hop popping comes in the action of the egress router. Based on its current configuration, the egress router signals different MPLS upstream to the penultimate router. A lvalue of 3 means the upstream router should perform PHP and forward native IPv4 packets. A lvalue of 0, on the other hand, tells the upstream router to perform a l-swap operation and to forward the data with an MPLS header attached. (We discuss the definitions of the MPLS label values in the "ls" section of this chapter.) A Juniper Networks router performs ultimate hop popping when the explicit-null command is applied. QUESTION 14 In normal operation, what is the job of the penultimate router? A. It pops the label and sends the remaining data packet to the egress router. B. It pushes an additional label on a packet and sends it to the egress router. C. It swaps an incoming label with a label of 3 and sends it to the egress router. D. It examines the IP packet and forwards the packet based on the destination IP address. Answer: A Explanation: The penultimate router, which is second to last along the path of the LSP, often performs a label pop operation to remove the MPLS information from the data packet. After consulting the MPLS switching table, the router forwards the resulting data, a native IPv4 packet, to the egress router. QUESTION 15 Where must you configure a static LSP? A. on the egress router only B. on the ingress router only C. on all routers along the LSP path D. on the ingress and egress routers Answer: A Explanation: A static label switched path requires that each router along the LSP be configured explicitly. QUESTION 16 You want to ensure that an LSP from router A to router D always goes through router C, which is two hops away. The ERO is configured as ____. A. C loose B. D loose C. C strict JN0-201 Actualtests.com - The Power of Knowing D. B strict Answer: A Explanation: The explicit route object (ERO) allows the path message to traverse the network using information that is independent of the IGP shortest path. An ERO configured with a loose hop specifies that the LSP must transit the specified node(s) in the order given. The IGP shortest path is used between the loose hop nodes. QUESTION 17 Which RSVP object assigns a label to the LSP? A. Label Object B. Label Assign Object C. Record Route Object D. Label Request Object Answer: A Explanation: Label Request Object The label request object is encoded in the Path messages sent to the egress router. This object allows each router to assign a label value to the requested LSP. When the Path message is received, the local router allocates a label and stores it with the Path soft state for that LSP. When the Resv message arrives from the downstream neighbor, the label is advertised upstream in an RSVP label object. QUESTION 18 If all OSPF routers on a broadcast network have the same OSPF priority, what parameter is used to determine the new BDR at the same time of a DR failure? A. area ID B. router ID C. loopback address D. IP address of interface on broadcast network Answer: A Explanation: The router priority of all participating routers is examined first, with the highest priority router becoming the BDR. Any router reporting a priority value of 0 is ineligible to become either the DR or BDR. In the event of a priority tie, the router ID of each router is examined. The highest value results in that router becoming the BDR. QUESTION 19 What is the purpouse of the OSPF link-state update packet? A. describes a change to the OSPF hello timer JN0-201 Actualtests.com - The Power of Knowing B. carries one or more link-state advertisements C. establishes and maintains neighbor relationships D. describes the contents of the entire link-state database Answer: A Explanation: Information in the link-state database is populated through a Link State Advertisement (LSA). Each LSA contains routing, metric, and topology information to describe a portion of the OSPF network. The local router advertises LSAs within a link-state update packet to its neighboring routers. QUESTION 20 Why would you make a non-backbone area a stub or not-so-stubby area? A. to aggregate routes learned from the ABR B. to lower the cost of routes advertised by the ABR C. to connect a non-contiguous area to the backbone D. to decrease the size of the link-state database in that area Answer: A Explanation: The OSPF stub area provides for a smaller link-state database by restricting the presence of AS external LSAs (type 5) within the area. A not-so-stubby area restricts type 5 external LSAs, but still allows for some external routes to be present in the database with a new NSSA external LSA type 7. QUESTION 21 What type of OSPF router is responsible for redistributing routes into OSPF? A. ABR B. ASBR C. internal router D. backbone router Answer: A Explanation: An Autonomous System boundary router (ASBR) connects networks running different routing protocols (autonomous systems). An ASBR injects external routing knowledge into an OSPF network. QUESTION 22 Which CLI command is used to see the current OSPF link-state database? A. show ospf database B. show ospf neighbor C. show protocols ospf JN0-201 Actualtests.com - The Power of Knowing D. show ospf link-state Answer: A Explanation: The "show ospf database" command shows summary information about each LSA on a per-area basis. QUESTION 23 During OSPF adjacency formation, in what state is a router when it is negotiating to be in charge of the database synchronization process? A. Init B. 2Way C. ExStart D. Exchange Answer: A Explanation: In the ExStart state, the local router and its neighbor establish which router is in charge of the database synchronization process. The higher router ID of the two neighbors controls which router becomes the master. QUESTION 24 Which three BGP states are associated with establishing TCP connectivity? (Choose three.) A. Idle B. Active C. Connect D. Open Sent E. Established Answer: A, B, C Explanation: IDLE: After the BGP process starts, a TCP session is initiated with the remote peer. The local router transitions to the Connect state and begins listening for a connection initiated by the remote peer. CONNECT: In this state, the local router is has seen a TCP connection attempt from a peer and is waiting for the TCP session to be completed. If it is successful, the local router sends an Open message to the peer and transitions to the OPENSENT state. ACTIVE: In the active state, the local router is trying to establish a TCP session with its peer. If the session establishes successfully, an Open message is sent and the local router transitions to the OPENSENT state. OPENSENT state is reached once TCP session is established. Established designates a fully operational OSPF connection [...]... transmitting data traffic destined for the multicast group address, the routers in the network flood the traffic to each segment in the network QUESTION 63 What version of IGMP is used default on juniper Networks routers? A version 1 only B version 2 only C version 3 only D version 4 only Answer: A Explanation: The basic configuration of IGMP within the JUNOS software is quite simple: do nothing Each... RP routers in a message called the RP-Set This process allows multiple RP routers to operate simultaneously and load-balances the protocol traffic across those routers QUESTION 66 How do you get a juniper Networks router to advertise OSPF routes to all BGP neighbors? A apply an import policy under [edit protocols ospf] that matches OSPF routes and accepts them B apply an export policy under [edit protocols... is created in both PIM-DM and PIM-SM? A root-based tree B core-based tree C shortest-path tree D receiver-based tree Answer: A Explanation: There are two different types of trees created by multicast networks: shared trees, and source-based trees Both trees create a shortest-path tree from the receiver back to the source QUESTION 46 What type of IGMP message is sent by a host to describe the multicast... message of concern to hosts: Host Membership Query, and Host Membership Report Multicast routers send Host Membership Query messages to discover which host groups have members on their attached local networks Hosts respond to a Query by generating Host Membership Reports reporting each host group to which they belong on the network interface from which the Query was received QUESTION 47 For what mode... policy within RIP that matches on the routes, and accepts it Answer: A Explanation: By default, the RIP protocol will have no knowledge of routes from other routing protocols including static routes On a Juniper router, routing policies are used to redistribute routes from one protocol to another To advertise any routes to a RIP neighbor, an export policy must be created QUESTION 36 How can you identify... is created in both PIM-DM and PIM-SM? A root-based tree B core-based tree C shortest-path tree D receiver-based tree Answer: A Explanation: There are two different types of trees created by multicast networks: shared trees, and source-based trees Both trees create a shortest-path tree from the receiver back to the source QUESTION 65 Which RP election mechanism can load balance among multiple candidate... routes F create a redistribution policy accepting the IS-IS routes Answer: B, F By default, the RIP protocol will have no knowledge of routes from other routing protocols including static routes On a Juniper router, routing policies are used to redistribute routes from one protocol to another For RIP to learn the ISIS routes, a policy must be configured to accept the ISIS routes For RIP to advertise... integrated with each other B Processes are fully independent from each other C Processes run in a protected memory environment D Processes may fail and cause a failure of the entire system Answer: B,C From Juniper. com, Benefits of the JUNOS operating system: Each user process runs in its own protected memory space This ensures that the failure of one subsystem will not negatively impact the operation of... system QUESTION 77 On which ASIC is queuing performed? A Incoming l/o Manager ASIC B Outgoing i/o Manager ASIC C Incoming Buffer Manager ASIC D Outgoing Buffer Manager ASIC Answer: A Explanation: The Internet processor ASIC sends the result cell to the Outbound Distributed Buffer Manager ASIC, which examines the cell to locate the outgoing interface The result cell is then sent to the appropriate FPC... removable media is used for disaster-recovery purposes QUESTION 80 Which SIC is responsible for transmitting a routed packet out an interface? A PIC l/o ASIC B I/O Manager ASIC C Buffer Manager ASIC D Internet Processor ASIC Answer: A Explanation: The PIC I/O ASIC performs any link-layer duties, if required, then transmits the data packet out the router's interface QUESTION 81 A failure of the internal . Exam : JN0-201 Title : Juniper Networks Certified Internet Associate Ver : 09.21.2006 JN0-201 Actualtests.com - The Power of Knowing . packet follow within a Juniper Networks router after it enters an interface and before a forwarding table lookup is performed? A. PIC I/O Manager, Buffer Manager, I/O Manager, Internet Processor. I/O Manager, Buffer Manager, Internet Processor, I/O Manager C. PIC I/O Manager, I/O Manager, Buffer Manager, Internet Processor D. PIC I/O Manager, I/O Manager, Internet Processor, Buffer Manager