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CCNP

Instructions:

Answer 50 questions in 15 minutes.
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Match each statement with the correct term.
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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. What is the multicast IP address space?
16 bit number 1 to 65535 1-64511: Public AS 64512-6535: Reserved for private AS BGP
BGP Table - BGP topology database - information BGP Neighbor Table - list of connected neighbors IP Routing Table - Duh. BGP
The router will not accept a routing update that includes its AS number in the path. BGP
Class D address space First bits are ALWAYS 1110 224.0.0.0 - 239.255.255.255 Multicast

2. Which IOS command shows what version of IGMP is running?
Router#show ip igmp interface fa0/0 Multicast
* = Best route > = Route has been inserted into the routing table BGP
Determines upstream and downstream interfaces. Uses the unicast routing table to insure that only one interface is considered to be and incoming interface for the source. RPF makes sure that if data is looped around is not forwarded. 
One-to-many: video distribution Many-to-many: Collaboration Many-to-one: auction - polling or data collection Few-to-many: auction - polling or data collection Multicast

3. Explain what role IGMP plays.
WM 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)' This insures a loop-free environment. If BGP receives a
Language between local router interface and hosts. IGMP - ICMP - similarities TTL is usually 1; RFC states it should never leave local subnet. Creates and maintains group membership for hosts wishing to participate in a multicast grou
This will advertise the entire classful network: R1(config-router)# network 10.1.1.0 This will advertise the the classless network: R1(config-router)# network 10.1.1.0 mask 255.255.255.0 BGP
Open - Version - AS - Hold Time - BGP Router ID - Optional Parameters Keepalive - Sent every 60 seconds by default; hold time 180 Seconds. Update - Information on only ONE path; Notification - When error condition detected BGP

4. Explain the Next-Hop attribute. How does this differ from IGP's? In what environment might this be problematic?
(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. (* -G) - 'Star comma G'; Any source sending to the group. Traffic forwar
One-to-many: video distribution Many-to-many: Collaboration Many-to-one: auction - polling or data collection Few-to-many: auction - polling or data collection Multicast
WM 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. in IBGP the next hop advertised by EBGP should
When AS has more than one connection to the Internet it is called multihoming. Inbound reliability Better performance by selecting more optimal paths Multihoming can be to one ISP or to several. BGP

5. What is the command to configure a BGP RR?
Local preference Atomic Aggregate 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
Router(config-router)# neighbor 192.168.1.1 remote-as 65000 Router(config-router)# neighbor 192.168.1.1 route-reflector-client BGP
Links = n(n-1)/2 BGP

6. State how IGMPv1 operates.
Group of BGP routers being configured that have the same update policy. Similar to a 'template'; members then assigned to the peer group. BGP
Class D address space First bits are ALWAYS 1110 224.0.0.0 - 239.255.255.255 Multicast
This will advertise the entire classful network: R1(config-router)# network 10.1.1.0 This will advertise the the classless network: R1(config-router)# network 10.1.1.0 mask 255.255.255.0 BGP
RFC 1112 Sends membership query every 60 - 120 seconds to 224.0.0.1 Hosts send membership report in response to the query Multicast

7. Name the Well-known mandatory attributes.
AS-Path Next Hop Origin BGP
Efficiency Performance Scalability with applications Multicast
Session description & announcement. Transport session announcement via 224.2.127.254. Creation of new sessions. Multicast
The Source and Share Tree models are the working model of how the tree is built; all multicast routing protocols fit into one or both. This is the 'theory' or model. PIM-DM's operational falls in the source tree model and PIM-SM is classified an

8. What advantage does multicast offer?
Member of a group: Router#(config) ip igmp join-group group-address Statically connected: Router#(config) ip igmp join-group group-address In this mode router forwards (fast switches) group packets but itself does not accept group
Cluster - combination of RR and its clients. Can have multiple clusters in an AS. Originator ID - carries router ID of the route's originator Cluster ID - configured when multiple RR in a cluster. Cluster list - sequence of cluster ID
Efficiency Performance Scalability with applications Multicast
'Periodic Flood and Prune.' 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. Prune messages are sent on all non-RPF interfaces and RPF int

9. What is the IOS command to check for IGMP group members? What info does it reveal?
Router#show ip igmp group Group address - interface - uptime - expires - and last reporter. Multicast
Use loopback interface to establish the neighbor. (i.e. peer to a loopback interface) Tell BGP to use the lookback interface as teh source of updates R1(config-router)# neighbor 192.168.1.1 update-source loopback0 BGP
Router(config-router)# neighbor 192.168.1.1 remote-as 65000 Router(config-router)# neighbor 192.168.1.1 route-reflector-client BGP
MOSPF DVMRP CBT PIM Dense Mode PIM Sparse Mode PIM Sparse-Dense Mode Multicast

10. IOS command to configure a rendezvous point .
BPG will find an exact match. BGP
Router#(config) ip pim send-rp-announce interface_type scope ttl group-list access-list Multicast
Variable length sequence of path attributes Attribute Type -1 byte flag field - 1 byte type code Attribute Length Attribute Value Attribute flag field = 0000 0000 W | O - T | N - P | C BGP
BGP not designed for load balancing (by default). BGP selected the SINGLE best path to a destination and places it in the routing table; the rest are kept in the BGP Table. Paths are chosen based on policy. BGP eliminates paths until one p

11. What are the commands to enable multicast routing on a router?
Language between local router interface and hosts. IGMP - ICMP - similarities TTL is usually 1; RFC states it should never leave local subnet. Creates and maintains group membership for hosts wishing to participate in a multicast grou
Globally: Router(config)# ip multicast-routing Per Interface: Router(config-if)# ip pim dense-mode Enabling PIM on an interface also enables IGMP operation on that interface. Multicast
WD Dictates which path is preferred to exit the AS. Higher is is preferred - default is 100 on Cisco. Obviously for this to be relevant there must be multiple exit points for the route. 'Influences outbound traffic for an AS'<br /
It actually determines which networks are advertised. BGP

12. What are three different common ways to perform BGP multihoming with regard to routing table?
ISP passes only default route to AS. ISP passes default route and provider owned select routes to AS. ISP passes all routes to AS. BGP
RFC 2362 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. Last hop routers to receiver knows the group RP IP address and sends a (* -G) join toward
Well-known Mandatory - Must be supported and propagated. Well-known Discretionary - Must be supported; propagation optional. Optional Transitive - Marked as partial if unsupported by neighbor. Option Nontransitive - Deleted is unsuppor
Links = n(n-1)/2 BGP

13. What is the command to configure a BGP RR? 
WD Dictates which path is preferred to exit the AS. Higher is is preferred - default is 100 on Cisco. Obviously for this to be relevant there must be multiple exit points for the route. 'Influences outbound traffic for an AS' Router(config-router)# neighbor 192.168.1.1 route-reflector-client BGP
ON Displayed as metric in Cisco IOS; lower is preferred. Default is 0. Indicated to external AS the preferred path into the AS. 'Influence inbound traffic to an AS' By default ONLY compares if neighbors AS is same for all routes being
Idle - Router looking in routing table to see if route exists to neighbor. [Active - When no response to Open message] Connect - Router found route to neighbor and has performed the TCP three-way handshake Open Sent

14. What is the difference between iBGP and eBGP?
Router#show ip igmp group Group address - interface - uptime - expires - and last reporter. Multicast
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 is an adjacency between BGP peers in different AS; iBGP peers are in same AS. BGP
R1(config-router)# neighbor 192.168.1.1 next-hop-self Cause each routers outgoing interface that the route traverse wihtin the AS (iBPG peers) to annouce itself as the 'next hop' instead of the next hop into the neighboring AS. 

15. What is a neighbor call in BGP?
Open - Version - AS - Hold Time - BGP Router ID - Optional Parameters Keepalive - Sent every 60 seconds by default; hold time 180 Seconds. Update - Information on only ONE path; Notification - When error condition detected BGP
Use loopback interface to establish the neighbor. (i.e. peer to a loopback interface) Tell BGP to use the lookback interface as teh source of updates R1(config-router)# neighbor 192.168.1.1 update-source loopback0 BGP
BGP peer BGP
RFC 2362 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. Last hop routers to receiver knows the group RP IP address and sends a (* -G) join toward

16. What are the methods to control multicast within the layer 2 domain? What are some benefits & drawbacks of each?
Members leave through attrition; no leave group message. This keep traffic flowing for a period of time even with no group members. Multicast
The router will not accept a routing update that includes its AS number in the path. BGP
Routes learned through IBPG are never propogated to other IBGP speakers. This is a loop prevention mechanism. BGP
IGMP Snooping - requires special ASICS can degrade performance with it; is supported by multiple vendors. CGMP - Cisco proprietary - only work on Cisco hardware; resource friendly GMRP - Replaced by MRP; obscure Manually - Performance

17. State 3 functions SDR performs?
IGMP Snooping - requires special ASICS can degrade performance with it; is supported by multiple vendors. CGMP - Cisco proprietary - only work on Cisco hardware; resource friendly GMRP - Replaced by MRP; obscure Manually - Performance
Default-Network Static route BGP
Session description & announcement. Transport session announcement via 224.2.127.254. Creation of new sessions. Multicast
Path Vector - policy based routing protocol. Uses BGP attributes are the 'metric'. Path it decides it based on 'hops' where hop is Autonomous Systems. BGP

18. Name several common local scoped multicast addresses and their purpose.
Router#(config) ip pim spt-threshold {rate | infinity} [group-list access-list] Multicast
224.0.0.1 - All systems 224.0.0.2 - All routers 224.0.0.4 - DVMRP routers 224.0.0.5 - All OSPF 224.0.0.6 - All OSPF DR 224.0.0.9 - RIP v2 routers 224.0.0.10 - EIGRP routers 224.0.0.13 - PIM routers 224.0.0.15 -
Reverse Path Forwarding is the forwarding logic multicast of multicast. It is the opposite of unicast in that is forwards AWAY from source as opposed to towards the receiver. Multicast
Routes learned through IBPG are never propogated to other IBGP speakers. This is a loop prevention mechanism. BGP

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

20. What are the 6 BGP Neighbor states?
BGP Table - BGP topology database - information BGP Neighbor Table - list of connected neighbors IP Routing Table - Duh. BGP
Idle - Router looking in routing table to see if route exists to neighbor. [Active - When no response to Open message] Connect - Router found route to neighbor and has performed the TCP three-way handshake Open Sent
Well-known Mandatory - Must be supported and propagated. Well-known Discretionary - Must be supported; propagation optional. Optional Transitive - Marked as partial if unsupported by neighbor. Option Nontransitive - Deleted is unsuppor
Links = n(n-1)/2 BGP

21. Name what an update message may include.
This router originated the route. BGP
Default-Network Static route BGP
Efficiency Performance Scalability with applications Multicast
Contains information on ONE path only Withdrawn routes - List of IP prefixes for routes being withdrawn. Path attributes - AS-Path - etc. Network layer reachability information - List of IP prefixes reachable by this path. BGP

22. Explain the contents of the BGP update message.
Source Tree - Source-based tree's are rooted at the source. Source tree created for each new group. Also called shortest path tree (SPT's). Shared Tree - Single tree that is shared between all sources; single common root called the rendezvous p
Show ip bgp - Shows entire BGP topology database (BGP table) show ip bgp rib-failure - Displays BGP routes not installd into the routing information base (RIB) and reason they were not installed. show ip bgp neighbors - Displays
Variable length sequence of path attributes Attribute Type -1 byte flag field - 1 byte type code Attribute Length Attribute Value Attribute flag field = 0000 0000 W | O - T | N - P | C BGP
Places it in the routing table. BGP

23. Explain the Community attribute.

24. What does PIM use for its multicast routing calculations?
WM One of three values: IGP - Route is interior to the originating AS. (BGP table shows 'i') EGP - Route learned via EGP. (BGP table shows 'e') Incomplete - Routes origin is unknown - usually when redistributed. (BGP table shows
The unicast routing table. No routing updates are sent between PIM routers. Multicast
The Source and Share Tree models are the working model of how the tree is built; all multicast routing protocols fit into one or both. This is the 'theory' or model. PIM-DM's operational falls in the source tree model and PIM-SM is classified an
SPT (S -G) consume more memory because there is an entry for each source BUT traffic is sent over optimal path to receiver. Shared distribution tree state entries (* -G) consume less CPU but may take suboptimal path to receiver. Multicast

25. Name a significant inefficiency with IGMPv1.
Contains information on ONE path only Withdrawn routes - List of IP prefixes for routes being withdrawn. Path attributes - AS-Path - etc. Network layer reachability information - List of IP prefixes reachable by this path. BGP
Members leave through attrition; no leave group message. This keep traffic flowing for a period of time even with no group members. Multicast
Local scoped: 224.0.0.0 - 224.0.0.255 TTL of 1; Never to leave local network - for routing protocols and other network maintenance. Global scoped: 224.0.1.0 - 238.255.255.255 MBone dynamically allocate throughout Internet Limited/
Update from client peer - sends update to all non-client peers and client peers except for originating peer. Update from non-client peer - send update to all clients in the cluster. Update from EBGP peer - update sent to all client peers an

26. What are two methods of establishing a gateway of last resort?
SPT (S -G) consume more memory because there is an entry for each source BUT traffic is sent over optimal path to receiver. Shared distribution tree state entries (* -G) consume less CPU but may take suboptimal path to receiver. Multicast
1. Weight - Administrative preference (Highest) 2. Local Preference - Communicated between peers within AS (Highest) 3. Self-originated - Prefer path originated locally (True) 4. AS Path - Minimize AS hops (Shortest)<
Default-Network Static route BGP
Partial mesh iBPG is where not all BGP speaks within and AS have an established neighbor relationship. Full mesh is every BGP speaker has a neighbor (peer) with each other. Routing updates are not replcated in iBPG the peers do not pass i

27. Explain how the multicast routing table is populated.
Dense mode interfaces are always added to the table. 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 Multi
Update from client peer - sends update to all non-client peers and client peers except for originating peer. Update from non-client peer - send update to all clients in the cluster. Update from EBGP peer - update sent to all client peers an
One-to-many: video distribution Many-to-many: Collaboration Many-to-one: auction - polling or data collection Few-to-many: auction - polling or data collection Multicast
The neighbor expects to see the updates from the source address configured in the neighbor statement. BGP

28. What does a 0.0.0.0 signify in the Next Hop column in the BGP Table?
The is the multicast bit. Multicast
R1# clear ip bgp R1# clear ip bgp soft in R1# clear ip bgp * soft out R1# clear ip bgp 10.1.1.1 soft in BGP
Efficiency Performance Scalability with applications Multicast
This router originated the route. BGP

29. What does a '*' and '>' mean in the BGP table?
Loopback more resilient than physical interfaces. BGP
* = Best route > = Route has been inserted into the routing table BGP
<img src='9618cf01b9422f541fc213b74a3bd9de.png' /> Multicast
Class D address space First bits are ALWAYS 1110 224.0.0.0 - 239.255.255.255 Multicast

30. Name 6 multicast routing protocols.
RFC 2362 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. Last hop routers to receiver knows the group RP IP address and sends a (* -G) join toward
BGP specifies that it can advertise to its peers in neighboring AS's only routes that it uses. BGP cannot influence how a neighboring AS will route your traffic BUT it can influence how your traffic gets to the neighboring AS. BGP
MOSPF DVMRP CBT PIM Dense Mode PIM Sparse Mode PIM Sparse-Dense Mode Multicast
Efficiency Performance Scalability with applications Multicast

31. What is the significance of the 8th bit in the MAC address?
Links = n(n-1)/2 BGP
224.0.0.1 - All systems 224.0.0.2 - All routers 224.0.0.4 - DVMRP routers 224.0.0.5 - All OSPF 224.0.0.6 - All OSPF DR 224.0.0.9 - RIP v2 routers 224.0.0.10 - EIGRP routers 224.0.0.13 - PIM routers 224.0.0.15 -
The is the multicast bit. Multicast
RFC 2236 Leave and join latency resolved Group specific query to G instead of 224.0.0.1 Leave group message Election of querier (lowest IP) on broadcast medium with multiple routers Multicast

32. What is one method involving minimal configuration to prevent and multi-homed BGP network from becoming a transit AS?
Using a Distribute List to filter outbound routing updates. BGP
Loopback more resilient than physical interfaces. BGP
WD Dictates which path is preferred to exit the AS. Higher is is preferred - default is 100 on Cisco. Obviously for this to be relevant there must be multiple exit points for the route. 'Influences outbound traffic for an AS' > = Route has been inserted into the routing table BGP

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

34. Describe 4 multicast application models and give an example of each?
Allow router to operate in sparse mode and dense mode at the same time. Supports multiple RP's and automatic RP selection for each multicast source. Support auto-RP - bootstrap router (BSR) or statically defined RP's with minimal configurat
One-to-many: video distribution Many-to-many: Collaboration Many-to-one: auction - polling or data collection Few-to-many: auction - polling or data collection Multicast
'Periodic Flood and Prune.' 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. Prune messages are sent on all non-RPF interfaces and RPF int
Well know predefined group Directory - sd / SDP Webpage/URL Email link Multicast

35. What command used to perform the following: A) Reset all neighbors session ('bounce') B) Soft inbound reset C) Soft outbound reset D) Soft inbound reset of neighbor 10.1.1.1 R1# clear ip bgp R1# clear ip bgp soft
EBGP will only peer to direclty connected neighbors and a loopback is considered one hop away. With eBGP peering to a loopback you must enable eBGP Multihop. R1(config-router)# neighbor 192.168.1.1 ebgp-multihop 2 BGP
Using a Distribute List to filter outbound routing updates. BGP
R1# clear ip bgp R1# clear ip bgp soft in R1# clear ip bgp * soft out R1# clear ip bgp 10.1.1.1 soft in BGP
Sends a leave message to 224.0.0.2 Router then sends a group specific query Remaining member(s) send a report so group remains active. Multicast

36. What is the hop-by-hop routing paradigm of BGP?

37. What are the administrative distances of eBGP and iBGP?
ISP passes only default route to AS. ISP passes default route and provider owned select routes to AS. ISP passes all routes to AS. BGP
Local scoped: 224.0.0.0 - 224.0.0.255 TTL of 1; Never to leave local network - for routing protocols and other network maintenance. Global scoped: 224.0.1.0 - 238.255.255.255 MBone dynamically allocate throughout Internet Limited/
EBGP = 20 iBGP = 200 BGP
The router will not accept a routing update that includes its AS number in the path. BGP

38. What is the terminology for BGP route reflector?

39. What is a BGP peer group?

40. What is BGP multihoming and why would you want to do it?
Local preference Atomic Aggregate BGP
When AS has more than one connection to the Internet it is called multihoming. Inbound reliability Better performance by selecting more optimal paths Multihoming can be to one ISP or to several. BGP
Unicast uses a routing table looking and forwards towards the destination address. Multicast forwards out multiple interfaces and away from the source and towards multiple destinations using a distribution tree. Multicast
BGP peer BGP

41. Explain the path selection process for BGP? What is the order and what preference does it take?
The Source and Share Tree models are the working model of how the tree is built; all multicast routing protocols fit into one or both. This is the 'theory' or model. PIM-DM's operational falls in the source tree model and PIM-SM is classified an
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. RR allow the propagation of routes learned by IBGP to other IBGP peers without having a full mesh of IBGP
ON Displayed as metric in Cisco IOS; lower is preferred. Default is 0. Indicated to external AS the preferred path into the AS. 'Influence inbound traffic to an AS' By default ONLY compares if neighbors AS is same for all routes being
1. Weight - Administrative preference (Highest) 2. Local Preference - Communicated between peers within AS (Highest) 3. Self-originated - Prefer path originated locally (True) 4. AS Path - Minimize AS hops (Shortest)<

42. How is the BGP network command differ from IGP's?
Class D address space First bits are ALWAYS 1110 224.0.0.0 - 239.255.255.255 Multicast
Works if router has multiple parallel paths to a destination. ONLY affect number of routes in IP routing table not the route selected at best in the BGP table. Will load balance across equal cost paths in EGP session. BGP
It actually determines which networks are advertised. BGP
Allow router to operate in sparse mode and dense mode at the same time. Supports multiple RP's and automatic RP selection for each multicast source. Support auto-RP - bootstrap router (BSR) or statically defined RP's with minimal configurat

43. What does BGP use for communication? What advantage does it offer?
TCP port 179 Reliability; uses sliding window Triggered - incremental updates made very efficient BGP
Efficiency Performance Scalability with applications Multicast
RFC - 3376 Ability to filter multicast source (can be picky) IGMPv3 membership report goes to 224.0.0.22 and may include the multicast hosts it will accept or deny. Multicast
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

44. Explain the IGMPv3 membership process and new features.
Idle - Router looking in routing table to see if route exists to neighbor. [Active - When no response to Open message] Connect - Router found route to neighbor and has performed the TCP three-way handshake Open Sent
Using a Distribute List to filter outbound routing updates. BGP
Router#show ip igmp group Group address - interface - uptime - expires - and last reporter. Multicast
RFC - 3376 Ability to filter multicast source (can be picky) IGMPv3 membership report goes to 224.0.0.22 and may include the multicast hosts it will accept or deny. Multicast

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

46. What are the basic commands to enable BGP - define a BGP peer relationship and advertise a network?
Router#(config) router bgp 1 Router#(config-router) neighbor 192.168.1.1 remote-as 1 Router#(config-router) network 192.168.0. mask 255.255.255.0 BGP
Contains information on ONE path only Withdrawn routes - List of IP prefixes for routes being withdrawn. Path attributes - AS-Path - etc. Network layer reachability information - List of IP prefixes reachable by this path. BGP
R1(config-router)#neighbor MyPeers peer-group R1(config-router)#neighbor 10.1.1.1 remote-as 64513 R1(config-router)#neighbor 10.1.1.1 peer-group MyPeers BGP
Rule: Router must be known by an IGP before it may be advertised by BGP peers. Prevents 'blackholes' when AS is a transit network and not all speaker are running BGP Should be left on it AS is a transit AS and not all routers run BGP. 

47. Explain the multicast routing table distribution tree notations.

48. Explain the way RR handles route updates.
Router(config-router)# neighbor 192.168.1.1 remote-as 65000 Router(config-router)# neighbor 192.168.1.1 route-reflector-client BGP
Update from client peer - sends update to all non-client peers and client peers except for originating peer. Update from non-client peer - send update to all clients in the cluster. Update from EBGP peer - update sent to all client peers an
Group of BGP routers being configured that have the same update policy. Similar to a 'template'; members then assigned to the peer group. BGP
Routes learned through IBPG are never propogated to other IBGP speakers. This is a loop prevention mechanism. BGP

49. Within the layer 3 multicast address space - name 3 reserved scopes and their purpose.
It actually determines which networks are advertised. BGP
Local scoped: 224.0.0.0 - 224.0.0.255 TTL of 1; Never to leave local network - for routing protocols and other network maintenance. Global scoped: 224.0.1.0 - 238.255.255.255 MBone dynamically allocate throughout Internet Limited/
MOSPF DVMRP CBT PIM Dense Mode PIM Sparse Mode PIM Sparse-Dense Mode Multicast
Member of a group: Router#(config) ip igmp join-group group-address Statically connected: Router#(config) ip igmp join-group group-address In this mode router forwards (fast switches) group packets but itself does not accept group

50. Name to enhancements to PIM.
Bidirection PIM mode - designed for many to many applications. Source Specific Multicast (SSM) ; builds only source specific shortest path trees. Multicast
16 bit number 1 to 65535 1-64511: Public AS 64512-6535: Reserved for private AS BGP
Update from client peer - sends update to all non-client peers and client peers except for originating peer. Update from non-client peer - send update to all clients in the cluster. Update from EBGP peer - update sent to all client peers an
Router#(config) ip pim spt-threshold {rate | infinity} [group-list access-list] Multicast