Instructions:

• Answer 50 questions in 15 minutes.
• If you are not ready to take this test, you can study here.
• Match each statement with the correct term.
• Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. Explain the BGP route decision process? How many routes does it select? Where do they go? Where do the ones go that are not used?
Determines upstream and downstream interfaces.<br />Uses the unicast routing table to insure that only one interface is considered to be and incoming interface for the source.<br />RPF makes sure that if data is looped around is not forwarded. <br />
RFC 2236<br />Leave and join latency resolved<br />Group specific query to G instead of 224.0.0.1<br />Leave group message<br />Election of querier (lowest IP) on broadcast medium with multiple routers <br /> Multicast
BGP not designed for load balancing (by default). <br />BGP selected the SINGLE best path to a destination and places it in the routing table; the rest are kept in the BGP Table.<br />Paths are chosen based on policy. BGP eliminates paths until one p
This router originated the route. BGP


2. Name 4 verification commands for BGP and what they display?
Works if router has multiple parallel paths to a destination.<br />ONLY affect number of routes in IP routing table not the route selected at best in the BGP table.<br />Will load balance across equal cost paths in EGP session.<br /> BGP
Show ip bgp - Shows entire BGP topology database (BGP table)<br /><br />show ip bgp rib-failure - Displays BGP routes not installd into the routing information base (RIB) and reason they were not installed.<br /><br />show ip bgp neighbors - Displays
Concatenation of the first (high order) 25 bits of the reserved MAC address range with the last (low order)23 bits of the multicast group IP address. 5 bits of overlap allowing for 32 address (2^5) for each multicast MAC address. 25 bits + 23 bits<br
The unicast routing table.<br />No routing updates are sent between PIM routers.<br /> Multicast


3. What are the 3 BGP tables and What is in them?
Places it in the routing table. BGP
BGP Table - BGP topology database - information <br />BGP Neighbor Table - list of connected neighbors<br />IP Routing Table - Duh.<br /> BGP
Class D address space<br />First bits are ALWAYS 1110<br />224.0.0.0 - 239.255.255.255<br /> Multicast
ON<br />Displayed as metric in Cisco IOS; lower is preferred. Default is 0. Indicated to external AS the preferred path into the AS.<br />'Influence inbound traffic to an AS'<br />By default ONLY compares if neighbors AS is same for all routes being


4. What are the 4 categories of BGP attributes and what do they mean?
Works if router has multiple parallel paths to a destination.<br />ONLY affect number of routes in IP routing table not the route selected at best in the BGP table.<br />Will load balance across equal cost paths in EGP session.<br /> BGP
The neighbor expects to see the updates from the source address configured in the neighbor statement. BGP
Well-known Mandatory - Must be supported and propagated.<br />Well-known Discretionary - Must be supported; propagation optional.<br />Optional Transitive - Marked as partial if unsupported by neighbor.<br />Option Nontransitive - Deleted is unsuppor
Links = n(n-1)/2 BGP


5. What are the two multicast distribution tree types models and differences?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


6. How is the BGP network command differ from IGP's?
Default-Network<br />Static route<br /> BGP
It actually determines which networks are advertised. BGP
Router(config-router)# neighbor 192.168.1.1 remote-as 65000<br />Router(config-router)# neighbor 192.168.1.1 route-reflector-client<br /> BGP
Since IBGP learned routes are never propagate to other IBGP peer - full mesh of IBPG peers is required within an AS. THIS IS NOT SCALABLE. <br />RR allow the propagation of routes learned by IBGP to other IBGP peers without having a full mesh of IBGP


7. Describe 4 multicast application models and give an example of each?
WD<br />Dictates which path is preferred to exit the AS.<br />Higher is is preferred - default is 100 on Cisco.<br />Obviously for this to be relevant there must be multiple exit points for the route.<br />'Influences outbound traffic for an AS'<br /
Router#show ip igmp group<br />Group address - interface - uptime - expires - and last reporter.<br /> Multicast
WM<br /><br />List of AS numbers pre-pended with a list of AS numbers that the route has traversed and the originating AS at the end. 'Path to 192.168.1.0 is (65500 - 65420 - 65874)'<br /><br />This insures a loop-free environment. If BGP receives a
One-to-many: video distribution<br />Many-to-many: Collaboration<br />Many-to-one: auction - polling or data collection<br />Few-to-many: auction - polling or data collection<br /> Multicast


8. IOS command to dictate when a leaf router (in PIM-SM) will switch from shared to source tree.
The neighbor expects to see the updates from the source address configured in the neighbor statement. BGP
The is the multicast bit. Multicast
Router#(config) ip pim spt-threshold {rate | infinity} [group-list access-list] Multicast
BGP specifies that it can advertise to its peers in neighboring AS's only routes that it uses.<br />BGP cannot influence how a neighboring AS will route your traffic BUT it can influence how your traffic gets to the neighboring AS. <br /> BGP


9. What is the BGP Synchronization requirement and What does is prevent? When should it be left disabled? When should it be enabled?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


10. What are the methods to control multicast within the layer 2 domain? What are some benefits &amp; drawbacks of each?
IGMP Snooping - requires special ASICS can degrade performance with it; is supported by multiple vendors.<br />CGMP - Cisco proprietary - only work on Cisco hardware; resource friendly<br />GMRP - Replaced by MRP; obscure<br />Manually - Performance
Router#show ip igmp interface fa0/0<br /> Multicast
'Periodic Flood and Prune.'<br />Initially floods multicast traffic (received on its RPF) to all its PIM neighbors. Traffic that arrives back at the router via a non-RPF is discarded.<br />Prune messages are sent on all non-RPF interfaces and RPF int
Contains information on ONE path only<br /><br />Withdrawn routes - List of IP prefixes for routes being withdrawn.<br />Path attributes - AS-Path - etc.<br />Network layer reachability information - List of IP prefixes reachable by this path. BGP


11. How does a host learn about available multicast streams?
Open - Version - AS - Hold Time - BGP Router ID - Optional Parameters<br />Keepalive - Sent every 60 seconds by default; hold time 180 Seconds.<br />Update - Information on only ONE path; <br />Notification - When error condition detected<br /> BGP
Well know predefined group<br />Directory - sd / SDP<br />Webpage/URL<br />Email link<br /> Multicast
BGP peer BGP
This router originated the route. BGP


12. IOS command to configure router to be a member of an IGMP group or statically connected member.
WD<br />Dictates which path is preferred to exit the AS.<br />Higher is is preferred - default is 100 on Cisco.<br />Obviously for this to be relevant there must be multiple exit points for the route.<br />'Influences outbound traffic for an AS'<br /
Path Vector - policy based routing protocol.<br />Uses BGP attributes are the 'metric'. <br />Path it decides it based on 'hops' where hop is Autonomous Systems.<br /> BGP
Member of a group:<br />Router#(config) ip igmp join-group group-address<br />Statically connected:<br />Router#(config) ip igmp join-group group-address<br />In this mode router forwards (fast switches) group packets but itself does not accept group
224.0.0.1 - All systems<br />224.0.0.2 - All routers<br />224.0.0.4 - DVMRP routers<br />224.0.0.5 - All OSPF<br />224.0.0.6 - All OSPF DR<br />224.0.0.9 - RIP v2 routers<br />224.0.0.10 - EIGRP routers<br />224.0.0.13 - PIM routers<br />224.0.0.15 -


13. How does RPF avoid routing loops?
WM<br />Next hop address is entry point into the next AS along the path to that destination network. It does a recursive lookup to the routing table which should have learned the route from its IGP.<br />in IBGP the next hop advertised by EBGP should
Allow router to operate in sparse mode and dense mode at the same time.<br />Supports multiple RP's and automatic RP selection for each multicast source.<br />Support auto-RP - bootstrap router (BSR) or statically defined RP's with minimal configurat
Determines upstream and downstream interfaces.<br />Uses the unicast routing table to insure that only one interface is considered to be and incoming interface for the source.<br />RPF makes sure that if data is looped around is not forwarded. <br />
Update from client peer - sends update to all non-client peers and client peers except for originating peer.<br />Update from non-client peer - send update to all clients in the cluster.<br />Update from EBGP peer - update sent to all client peers an


14. What is the significance of an AS being a transit AS?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


15. What is the IBGP Split Horizon rule? What does this accomplish?
Session description &amp; announcement.<br />Transport session announcement via 224.2.127.254.<br />Creation of new sessions.<br /> Multicast
WM<br />One of three values: <br />IGP - Route is interior to the originating AS. (BGP table shows 'i')<br />EGP - Route learned via EGP. (BGP table shows 'e')<br />Incomplete - Routes origin is unknown - usually when redistributed. (BGP table shows
Variable length sequence of path attributes<br />Attribute Type -1 byte flag field - 1 byte type code<br />Attribute Length <br />Attribute Value<br />Attribute flag field = 0000 0000<br />W | O - T | N - P | C<br /> BGP
Routes learned through IBPG are never propogated to other IBGP speakers.<br /><br />This is a loop prevention mechanism. BGP


16. Explain the multicast routing table distribution tree notations.

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


17. Explain the path selection process for BGP? What is the order and what preference does it take?
BGP not designed for load balancing (by default). <br />BGP selected the SINGLE best path to a destination and places it in the routing table; the rest are kept in the BGP Table.<br />Paths are chosen based on policy. BGP eliminates paths until one p
1. Weight - Administrative preference (Highest)<br /><br />2. Local Preference - Communicated between peers within AS (Highest)<br /><br />3. Self-originated - Prefer path originated locally (True)<br /><br />4. AS Path - Minimize AS hops (Shortest)<
Router#(config) router bgp 1<br />Router#(config-router) neighbor 192.168.1.1 remote-as 1<br />Router#(config-router) network 192.168.0. mask 255.255.255.0<br /> BGP
BPG will find an exact match. BGP


18. What does the 'maximum-paths router' command facilitate?
Concatenation of the first (high order) 25 bits of the reserved MAC address range with the last (low order)23 bits of the multicast group IP address. 5 bits of overlap allowing for 32 address (2^5) for each multicast MAC address. 25 bits + 23 bits<br
EBGP will only peer to direclty connected neighbors and a loopback is considered one hop away.<br /><br />With eBGP peering to a loopback you must enable eBGP Multihop.<br /><br />R1(config-router)# neighbor 192.168.1.1 ebgp-multihop 2 BGP
RFC 2362<br />Pull model - traffic only forwarded to the parts of the network that need it. Sender registers with the RP which is a proxy to group members.<br />Last hop routers to receiver knows the group RP IP address and sends a (* -G) join toward
Works if router has multiple parallel paths to a destination.<br />ONLY affect number of routes in IP routing table not the route selected at best in the BGP table.<br />Will load balance across equal cost paths in EGP session.<br /> BGP


19. Explain the methods of advertising networks in BGP.
This will advertise the entire classful network:<br />R1(config-router)# network 10.1.1.0<br /><br />This will advertise the the classless network:<br />R1(config-router)# network 10.1.1.0 mask 255.255.255.0<br /><br /> BGP
One-to-many: video distribution<br />Many-to-many: Collaboration<br />Many-to-one: auction - polling or data collection<br />Few-to-many: auction - polling or data collection<br /> Multicast
Determines upstream and downstream interfaces.<br />Uses the unicast routing table to insure that only one interface is considered to be and incoming interface for the source.<br />RPF makes sure that if data is looped around is not forwarded. <br />
When not all routers within a transit AS have consistent routing information - due to not running BGP or misconfiguration or BPG speakers. Routing information is advertised but since not all routers within AS can reach the destination traffic is halt


20. What are some disadvantages of multicast?
IGMP is a layer 3 protocol<br />Switches treat multicast just like broadcast (forward out all ports except the one one which is was received)<br />By definition a pure layer 2 devices do not have a mechanism to see IGMP packets or facilitate the rela
Most applications rely on UDP<br />Security issues<br />Out of order delivery &amp; duplicate packets are a possibility during topology changes.<br />Lack of windowing/congestion control.<br /> Multicast
This router originated the route. BGP
Concatenation of the first (high order) 25 bits of the reserved MAC address range with the last (low order)23 bits of the multicast group IP address. 5 bits of overlap allowing for 32 address (2^5) for each multicast MAC address. 25 bits + 23 bits<br


21. What is the layer 2 multicast address and how is it formed? What potential problem is there with this?
Concatenation of the first (high order) 25 bits of the reserved MAC address range with the last (low order)23 bits of the multicast group IP address. 5 bits of overlap allowing for 32 address (2^5) for each multicast MAC address. 25 bits + 23 bits<br
Use loopback interface to establish the neighbor. (i.e. peer to a loopback interface)<br />Tell BGP to use the lookback interface as teh source of updates<br /><br />R1(config-router)# neighbor 192.168.1.1 update-source loopback0<br /> BGP
It actually determines which networks are advertised. BGP
Router(config-router)# neighbor 192.168.1.1 remote-as 65000<br />Router(config-router)# neighbor 192.168.1.1 route-reflector-client<br /> BGP


22. Which IOS command shows what version of IGMP is running?
The router will not accept a routing update that includes its AS number in the path. BGP
EBGP is an adjacency between BGP peers in different AS; iBGP peers are in same AS. BGP
Router#show ip igmp interface fa0/0<br /> Multicast
Local scoped: 224.0.0.0 - 224.0.0.255<br />TTL of 1; Never to leave local network - for routing protocols and other network maintenance.<br />Global scoped: 224.0.1.0 - 238.255.255.255<br />MBone dynamically allocate throughout Internet<br />Limited/


23. What advantage is there it establishing a neighbor relationship using a loopback interface?
Loopback more resilient than physical interfaces. BGP
When not all routers within a transit AS have consistent routing information - due to not running BGP or misconfiguration or BPG speakers. Routing information is advertised but since not all routers within AS can reach the destination traffic is halt
EBGP = 20<br />iBGP = 200<br /> BGP
Concatenation of the first (high order) 25 bits of the reserved MAC address range with the last (low order)23 bits of the multicast group IP address. 5 bits of overlap allowing for 32 address (2^5) for each multicast MAC address. 25 bits + 23 bits<br


24. What command used to perform the following:<br />A) Reset all neighbors session ('bounce')<br />B) Soft inbound reset<br />C) Soft outbound reset<br />D) Soft inbound reset of neighbor 10.1.1.1<br /><br />R1# clear ip bgp <br />R1# clear ip bgp soft
Routes learned through IBPG are never propogated to other IBGP speakers.<br /><br />This is a loop prevention mechanism. BGP
Session description &amp; announcement.<br />Transport session announcement via 224.2.127.254.<br />Creation of new sessions.<br /> Multicast
R1# clear ip bgp <br />R1# clear ip bgp soft in<br />R1# clear ip bgp * soft out<br />R1# clear ip bgp 10.1.1.1 soft in<br /><br /> BGP
<img src='9618cf01b9422f541fc213b74a3bd9de.png' /> Multicast


25. Name the Well-known mandatory attributes.
Rule: Router must be known by an IGP before it may be advertised by BGP peers.<br />Prevents 'blackholes' when AS is a transit network and not all speaker are running BGP<br />Should be left on it AS is a transit AS and not all routers run BGP.<br />
IANA delegates to Regional Internet Registries (RIRs):<br />ARIN - AfriNIC - APNIC - LACNIC and RIPE NCC<br /> BGP
* = Best route<br />&gt; = Route has been inserted into the routing table<br /> BGP
AS-Path<br />Next Hop<br />Origin BGP


26. What type of protocol is BGP classified as? What is its decision engine?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


27. What is the full mesh versus partial mesh IBGP and What are the implications of each?
Sends a leave message to 224.0.0.2<br />Router then sends a group specific query<br />Remaining member(s) send a report so group remains active.<br /> Multicast
Update from client peer - sends update to all non-client peers and client peers except for originating peer.<br />Update from non-client peer - send update to all clients in the cluster.<br />Update from EBGP peer - update sent to all client peers an
Routes learned through IBPG are never propogated to other IBGP speakers.<br /><br />This is a loop prevention mechanism. BGP
Partial mesh iBPG is where not all BGP speaks within and AS have an established neighbor relationship. <br />Full mesh is every BGP speaker has a neighbor (peer) with each other. <br />Routing updates are not replcated in iBPG the peers do not pass i


28. Explain the concept of RPF.
Members leave through attrition; no leave group message. This keep traffic flowing for a period of time even with no group members. Multicast
IGMP Snooping - requires special ASICS can degrade performance with it; is supported by multiple vendors.<br />CGMP - Cisco proprietary - only work on Cisco hardware; resource friendly<br />GMRP - Replaced by MRP; obscure<br />Manually - Performance
Well-known Mandatory - Must be supported and propagated.<br />Well-known Discretionary - Must be supported; propagation optional.<br />Optional Transitive - Marked as partial if unsupported by neighbor.<br />Option Nontransitive - Deleted is unsuppor
Reverse Path Forwarding is the forwarding logic multicast of multicast. <br />It is the opposite of unicast in that is forwards AWAY from source as opposed to towards the receiver.<br /> Multicast


29. What command will produce the following output and What is it displaying?<br /><br /><img src='5d3c9233dd205ee4319ef0ac2fc07460.jpg' />
* = Best route<br />&gt; = Route has been inserted into the routing table<br /> BGP
The BGP Table<br /><br />Command = show ip bgp BGP
Router#(config) router bgp 1<br />Router#(config-router) neighbor 192.168.1.1 remote-as 1<br />Router#(config-router) network 192.168.0. mask 255.255.255.0<br /> BGP
It actually determines which networks are advertised. BGP


30. What are the 6 BGP Neighbor states?
Use loopback interface to establish the neighbor. (i.e. peer to a loopback interface)<br />Tell BGP to use the lookback interface as teh source of updates<br /><br />R1(config-router)# neighbor 192.168.1.1 update-source loopback0<br /> BGP
Members leave through attrition; no leave group message. This keep traffic flowing for a period of time even with no group members. Multicast
Default-Network<br />Static route<br /> BGP
Idle - Router looking in routing table to see if route exists to neighbor. <br /><br />[Active - When no response to Open message] <br /><br />Connect - Router found route to neighbor and has performed the TCP three-way handshake<br /><br />Open Sent


31. What special consideration is there when peering to a eBGP neighbor using a loopback? What is the solution to this?
Router(config-router)# neighbor 192.168.1.1 remote-as 65000<br />Router(config-router)# neighbor 192.168.1.1 route-reflector-client<br /> BGP
Must insure loopback is reachable in the routing table. BGP
EBGP will only peer to direclty connected neighbors and a loopback is considered one hop away.<br /><br />With eBGP peering to a loopback you must enable eBGP Multihop.<br /><br />R1(config-router)# neighbor 192.168.1.1 ebgp-multihop 2 BGP
Update from client peer - sends update to all non-client peers and client peers except for originating peer.<br />Update from non-client peer - send update to all clients in the cluster.<br />Update from EBGP peer - update sent to all client peers an


32. Explain how the multicast routing table is populated.
Well know predefined group<br />Directory - sd / SDP<br />Webpage/URL<br />Email link<br /> Multicast
'Periodic Flood and Prune.'<br />Initially floods multicast traffic (received on its RPF) to all its PIM neighbors. Traffic that arrives back at the router via a non-RPF is discarded.<br />Prune messages are sent on all non-RPF interfaces and RPF int
TCP port 179<br />Reliability; uses sliding window<br />Triggered - incremental updates made very efficient<br /> BGP
Dense mode interfaces are always added to the table. <br /><br />Sparse mode interfaces are added to the table only when periodic join messages are received from downstream routers - or when a directly connected member is on the interface<br /> Multi


33. What is the multicast IP address space?
One-to-many: video distribution<br />Many-to-many: Collaboration<br />Many-to-one: auction - polling or data collection<br />Few-to-many: auction - polling or data collection<br /> Multicast
Group of BGP routers being configured that have the same update policy.<br />Similar to a 'template'; members then assigned to the peer group.<br /> BGP
When using the <span style='font-style:italic;'>classful</span> method - at least one subnet of the classful range must reside in the IP routing table.<br /><br />When using the <span style='font-style:italic;'>classless</span> method the exact subne
Class D address space<br />First bits are ALWAYS 1110<br />224.0.0.0 - 239.255.255.255<br /> Multicast


34. What does a '*' and '&gt;' mean in the BGP table?
Local preference<br />Atomic Aggregate BGP
* = Best route<br />&gt; = Route has been inserted into the routing table<br /> BGP
<img src='9618cf01b9422f541fc213b74a3bd9de.png' /> Multicast
IGMP is a layer 3 protocol<br />Switches treat multicast just like broadcast (forward out all ports except the one one which is was received)<br />By definition a pure layer 2 devices do not have a mechanism to see IGMP packets or facilitate the rela


35. Explain CGMP.

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


36. What are some of the obstacles with IGMP and multicast in general as it relates to layer 2/switches?
IGMP is a layer 3 protocol<br />Switches treat multicast just like broadcast (forward out all ports except the one one which is was received)<br />By definition a pure layer 2 devices do not have a mechanism to see IGMP packets or facilitate the rela
This will advertise the entire classful network:<br />R1(config-router)# network 10.1.1.0<br /><br />This will advertise the the classless network:<br />R1(config-router)# network 10.1.1.0 mask 255.255.255.0<br /><br /> BGP
'Periodic Flood and Prune.'<br />Initially floods multicast traffic (received on its RPF) to all its PIM neighbors. Traffic that arrives back at the router via a non-RPF is discarded.<br />Prune messages are sent on all non-RPF interfaces and RPF int
Efficiency<br />Performance<br />Scalability with applications<br /> Multicast


37. Explain the AS-Path attribute.

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


38. What are three different common ways to perform BGP multihoming with regard to routing table?
0100.5e00.0000 - 0100.5e7f.ffff - IANA reserved. Multicast
ON<br />Displayed as metric in Cisco IOS; lower is preferred. Default is 0. Indicated to external AS the preferred path into the AS.<br />'Influence inbound traffic to an AS'<br />By default ONLY compares if neighbors AS is same for all routes being
Path Vector - policy based routing protocol.<br />Uses BGP attributes are the 'metric'. <br />Path it decides it based on 'hops' where hop is Autonomous Systems.<br /> BGP
ISP passes only default route to AS.<br />ISP passes default route and provider owned select routes to AS.<br />ISP passes all routes to AS.<br /> BGP


39. Explain the Local Preference attribute.<br />

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


40. What is the command to configure a BGP RR?<br />
Router(config-router)# neighbor 192.168.1.1 remote-as 65000<br />Router(config-router)# neighbor 192.168.1.1 route-reflector-client<br /> BGP
RFC 2236<br />Leave and join latency resolved<br />Group specific query to G instead of 224.0.0.1<br />Leave group message<br />Election of querier (lowest IP) on broadcast medium with multiple routers <br /> Multicast
R1(config-router)#neighbor MyPeers peer-group<br />R1(config-router)#neighbor 10.1.1.1 remote-as 64513<br />R1(config-router)#neighbor 10.1.1.1 peer-group MyPeers<br /> BGP
One-to-many: video distribution<br />Many-to-many: Collaboration<br />Many-to-one: auction - polling or data collection<br />Few-to-many: auction - polling or data collection<br /> Multicast


41. Explain the Community attribute.

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


42. Within the layer 3 multicast address space - name 3 reserved scopes and their purpose.
R2(config)# access-list 1 permit 192.168.0.0 0.0.0.255<br />R1(config-router)# neighbor 10.1.1.1 distribute-list 1 out<br />R1(config-router)# neighbor 10.1.1.2 distribute-list 1 out<br /> BGP
Unicast uses a routing table looking and forwards towards the destination address.<br />Multicast forwards out multiple interfaces and away from the source and towards multiple destinations using a distribution tree.<br /> Multicast
Member of a group:<br />Router#(config) ip igmp join-group group-address<br />Statically connected:<br />Router#(config) ip igmp join-group group-address<br />In this mode router forwards (fast switches) group packets but itself does not accept group
Local scoped: 224.0.0.0 - 224.0.0.255<br />TTL of 1; Never to leave local network - for routing protocols and other network maintenance.<br />Global scoped: 224.0.1.0 - 238.255.255.255<br />MBone dynamically allocate throughout Internet<br />Limited/


43. What is the command to enable BPG authentication?
One-to-many: video distribution<br />Many-to-many: Collaboration<br />Many-to-one: auction - polling or data collection<br />Few-to-many: auction - polling or data collection<br /> Multicast
Allow router to operate in sparse mode and dense mode at the same time.<br />Supports multiple RP's and automatic RP selection for each multicast source.<br />Support auto-RP - bootstrap router (BSR) or statically defined RP's with minimal configurat
R1(config-router)#neighbor 192.168.1.1 password MyPassword<br /><br />OR<br /><br />R1(config-router)#neighbor MyPeerGroup password MyPassword<br /> BGP
EBGP = 20<br />iBGP = 200<br /> BGP


44. When creating a BGP neighbor relationship to a loopback interface what must be remember in the context of routing?
Language between local router interface and hosts.<br />IGMP - ICMP - similarities <br />TTL is usually 1; RFC states it should never leave local subnet.<br />Creates and maintains group membership for hosts wishing to participate in a multicast grou
Must insure loopback is reachable in the routing table. BGP
Router#(config) router bgp 1<br />Router#(config-router) neighbor 192.168.1.1 remote-as 1<br />Router#(config-router) network 192.168.0. mask 255.255.255.0<br /> BGP
OT<br />Allows the router to 'tag' and thus implement policy based on this tag.<br /> BGP


45. State how IGMPv1 operates.
Routes learned through IBPG are never propogated to other IBGP speakers.<br /><br />This is a loop prevention mechanism. BGP
Show ip bgp - Shows entire BGP topology database (BGP table)<br /><br />show ip bgp rib-failure - Displays BGP routes not installd into the routing information base (RIB) and reason they were not installed.<br /><br />show ip bgp neighbors - Displays
RFC 1112<br />Sends membership query every 60 - 120 seconds to 224.0.0.1<br />Hosts send membership report in response to the query<br /> Multicast
EBGP is an adjacency between BGP peers in different AS; iBGP peers are in same AS. BGP


46. What command is used to override the Next-Hop attribute of BGP? What does this do and when would you use this?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


47. What entities are responsible for allocating BGP AS numbers?
Open - Version - AS - Hold Time - BGP Router ID - Optional Parameters<br />Keepalive - Sent every 60 seconds by default; hold time 180 Seconds.<br />Update - Information on only ONE path; <br />Notification - When error condition detected<br /> BGP
Members leave through attrition; no leave group message. This keep traffic flowing for a period of time even with no group members. Multicast
Default-Network<br />Static route<br /> BGP
IANA delegates to Regional Internet Registries (RIRs):<br />ARIN - AfriNIC - APNIC - LACNIC and RIPE NCC<br /> BGP


48. State 3 functions SDR performs?
(S -G) - 'S comma G'; Source sending to the group. Typically reflect a source tree but can appear on a shared tree. Traffic forwarded via the shortest path from the source.<br />(* -G) - 'Star comma G'; Any source sending to the group. Traffic forwar
224.0.0.1 - All systems<br />224.0.0.2 - All routers<br />224.0.0.4 - DVMRP routers<br />224.0.0.5 - All OSPF<br />224.0.0.6 - All OSPF DR<br />224.0.0.9 - RIP v2 routers<br />224.0.0.10 - EIGRP routers<br />224.0.0.13 - PIM routers<br />224.0.0.15 -
Session description &amp; announcement.<br />Transport session announcement via 224.2.127.254.<br />Creation of new sessions.<br /> Multicast
MOSPF<br />DVMRP<br />CBT<br />PIM Dense Mode<br />PIM Sparse Mode<br />PIM Sparse-Dense Mode<br /> Multicast


49. What is the IOS command to check for IGMP group members? What info does it reveal?
Member of a group:<br />Router#(config) ip igmp join-group group-address<br />Statically connected:<br />Router#(config) ip igmp join-group group-address<br />In this mode router forwards (fast switches) group packets but itself does not accept group
Router#show ip igmp group<br />Group address - interface - uptime - expires - and last reporter.<br /> Multicast
Sends a leave message to 224.0.0.2<br />Router then sends a group specific query<br />Remaining member(s) send a report so group remains active.<br /> Multicast
SPT (S -G) consume more memory because there is an entry for each source BUT traffic is sent over optimal path to receiver.<br />Shared distribution tree state entries (* -G) consume less CPU but may take suboptimal path to receiver.<br /> Multicast


50. Name the Well-known discretionary attributes.
Must insure loopback is reachable in the routing table. BGP
O<br />Cisco only.<br />Routes with higher weight are preferred (0 - 65535) . Paths that the router originates have 32768; other paths have default of 0.<br /> BGP
Local preference<br />Atomic Aggregate BGP
Members leave through attrition; no leave group message. This keep traffic flowing for a period of time even with no group members. Multicast