Sequential order based on sequence numbers

All packets are matched.

Explicitly configured name

The then-current routing table

False: After a particular route is matched by the route map, it is not processed beyond that matching route-map command (specific to route redistribution). 

The permit or deny parameter in the route-map statement. The route is redistributed when the route-map command has the permit parameter, and not redistributed when it has the deny parameter.

Network 1.0.0.0 is not considered

The routes are processed by the next route-map clause, or not redistributed if there are no further clauses.

The routes are either filtered (if matched) or left in the list of routes to be examined by the next route-map clause (if not matched), if any.

The route is not filtered, it just doesn't match that particular route-map clause.

Configure a clause at the end with a permit action, but no match statements.

The route is matched only if all of the match statements parameters match the route.

False: Routes matched for redistribution can also have various attributes (such as the metric) set as the route is redistributed.

All routes whose first octet is 10 that have an exact prefix length of 24.

All routes whose first octet is 10 that have a prefix length between 8 and 24, inclusive.

Routes from different sources (protocols) have different non-comparable metrics. The lowest AD is used to choose which route gets installed into the routing table when identical routes (prefix and length) are present from multiple sources. 

0

1

5

20

90

100

110

115

120

OSPF is 110

170

200

255

With the distance command under the particular routing protocol's subconfiguration.

True. The distance command can be used under the subconfiguration of the particular routing protocol, and individual routes and ACLs can be referenced and modified.

True. With the distance command under the OSPF subconfiguration, individual route types (inter-area, intra-area, external) can have their AD value modified individually.

Routes from BGP, IS-IS, OSPF, or RIP will not be redistributed into EIGRP until a metric is set. You can specify different metrics per-route, per-protocol, or set a default metric. However, until a metric is configured (whether default or more specific), IOS accepts the redistribution commands, but will not actually redistribute the routes.

160

Static routes are redistributed into RIP with a metric of 1 (directly connected), unless otherwise set with the default or more-specific metric.

The routes are redistributed with an automatic default cost of 20 (IGP) or 1 (BGP) and are of route type E2.

The route will be redistributed with a metric of 0. A metric of 0 is incompatible with RIP and EIGRP. OSPF will assign a default metric of 20 (IGP) or 1 (BGP) unless otherwise specified.

Only major (classful) networks are redistributed. For example, if the source protocol contained the prefix 172.16.10.0/24 to be redistributed, it will be redistributed as 172.16.0.0/16 without the subnets keyword.

False. All EIGRP metric values must be set when redistributing into EIGRP, regardless of the K-values settings.

Routes from the source protocol in the then-current IP routing table

True

-Reference a route-map from the redistribute command that uses the set metric command

Using the redistribute command that references a route-map.

Using the metric option on the redistribute command.

The default-metric command under the router protocol process.

The metric-type option lets you set the route type of the redistributed routes. For example, OSPF defaults to E2 routes, but you can use the metric-type option to force the redistributed routes to be E1 instead.

A route redistributed into a lower-AD protocol by one router will be learned by another router, which will then use that redistributed route instead of a potentially more optimal route presented by a higher-AD protocol. 

Under the routing protocol process:

By filtering routes with the specified tags, the routes are never entered into the routing table, whereas when you set a higher Administrative Distance instead, the routes are still present but are not used unless the lower-AD route is removed from the routing table.

The route with the lowest cost to the ASBR wins.

The metric advertised by the summary is that of the current lowest-metric component subnet.

False, the router does not advertise the component subnets by default.

False, the router does not advertise the summary when its routing table does not have any of the component subnets.

The summarizing router creates a Local discard route to the summary, with destination Null0, to prevent routing loops.

Summary routes decrease the amount of specific information in the routing tables, which can sometimes cause suboptimal routing.

EIGRP summarization is configured on the interface in classic mode, or the af-interface in named mode:

Under the EIGRP process:

Even if the component route with the lowest metric remains the lowest, the summary metric is recalculated every time any individual component subnet metric changes, which adds to router overhead.

Under the EIGRP process:

OSPF routers in the same area must have identical LSDBs after flooding is complete, therefore all routers in an OSPF area must have the same summary routes, they all must be missing the same component subnets of each summary.

Under the OSPF process:

Under the OSPF process:

With ip classless, if a packet's destination does not match a specific route in the IP routing table, the router uses the default route.

Static route to 0.0.0.0, with the redistribute static command

Of these four, only the default-information originate command will cause OSPF to advertise a default route.

RIP, OSPF, and IS-IS

True

Best AD

True: OSPF requires the default-information originate command, which tells OSPF to redistribute any default routes found in the routing table, whether static or from another routing protocol.

Cost 1

False. OSPF uses default-information originate

RIP advertises a route to 0.0.0.0/0

The EIGRP default summary creates the route 0.0.0.0/0 with the destination null0. The EIGRP summary has a default AD of 5, so that route will be used instead of the eBGP route with its default AD of 20.

The local router creates a local summary route with destination null0 using AD 5. EIGRP then advertises the summary to other routers with AD 90 (EIGRP internal)

Profile

To learn flows that have high latency and throughput. Traffic being profiled is referred to as a traffic class. The list of all monitored traffic classes (MTC) is referred to as an MTC list.

To collect and compute performance metrics for the traffic identified in the Monitored Traffic Classes (MTC) list.

To create low and high thresholds to define in-policy and out-of-policy performance categories.

To influence traffic by manipulating routing or by using policy-based routing (PBR).

After controls have been introduced, PfR will verify out-of-policy event performance and make necessary adjustments to bring back in-policy performance.

Internal

Interfaces that are used to connect to the internal network for communication with the control plane manager, the Master Controller.

Interfaces used to transmit packets out of the local network. At least two external interfaces are required to successfully deploy PfR. These are the interfaces where prefixes and exit link performance will be monitored.

Interfaces used in the formation of the control plane mechanism that drives the PfR process. The local interface defines the source interface that is used to communicate to the Master Controller.

False: Authentication is mandatory, and performed with key chains.

False. However, the MC must be reachable by the border routers.

10

True. Authentication is still required.

Border routers report prefix and transit link measurements back to the MC, and enforce policy changes as instructed from the MC, such as injecting preferred routes to alter the course of packet flows in the network.

Configure the authentication key-chain.

pfr master in global configuration mode.

From the Master Controller:

Create the authentication key-chain to be used to communicate with the Master Controller.

At least two configured and reachable external interfaces from the Border router(s).

NetFlow is used to monitor: 

IP SLA probes are used to monitor:

60 seconds

Identify traffic to be optimized

The result is usually that most routes are propagated correctly, but some are not propagated.

30

33434

destination, source

By listening to the Layer 2 multicast address derived from the Layer 3 multicast address.

IANA

224.0.0.0 - 224.0.1.255

232.0.0.0/8

233.0.0.0/8

GLOP addresses

239.0.0.0/8

Transient

224.0.0.0/24

224.0.1.0/24

To allow a host to select a source for the multicast group.

The multicast MAC OUI will always be 01-00-5E

There are 32 non-contiguous IP multicast addresses mapped to each multicast MAC address. This means when a host joins a multicast group, it implicitly joins 31 other groups as well.

Without IGMP snooping or CGMP, multicast traffic is treated identically to broadcast and unknown unicast traffic in that it is flooded out of all ports in the VLAN because the Source Address is unknown. A Multicast MAC address is never used as a Source Address.

IP Protocol 2

To inform a local multicast router that a host wants to receive multicast traffic for a specific group, or leave that group.

Hosts, routers

IGMPv2

False: IGMP is automatically enabled when multicast routing and PIM are configured on a router.

False: The IGMP version can be changed per-interface, with IGMPv2 being the default for IOS 15.

Membership Query (type code 0x11)

The IGMPv2 Version 1 Membership Report message type is used by IGMPv2 hosts for backward compatibility with IGMPv1.

The IGMPv2 Version 2 Membership Report is sent by a group member to inform the router that at least one group member is present on the subnet.

The IGMPv2 Leave Group message type is sent by a group member if it was the last member to send a Membership Report to inform the router that it is leaving the group.

General Query messages set the Group Address field to 0.0.0.0.

True. IGMPv2 Type Codes 0x11 and 0x12 match the type codes for IGMPv1 Membership Query and Membership Report messages, which enables IGMPv2 hosts and routers to recognize IGMPv1 messages when IGMPv1 hosts or routers are on the network.

Leave Group messages

With a Leave Group message

A Group-Specific Query message

The effect is that hosts' collective IGMPv2 Solicited Report messages are spread out over a longer period of time, which results in more uniform consumption of subnet bandwidth and router resources.

Every 60 seconds

SA: Router interface's IP and MAC

1. Hosts join a particular multicast group and listen on two additional multicast MAC addresses: the calculated MAC corresponding to the multicast group, and the MAC 0100.5e00.0001 corresponding to 224.0.0.1 (all nodes).

The router's interface will forward multicast traffic whether a single host, or multiple hosts belong to a given multicast group, and therefore additional Membership Report messages from multiple hosts are unnecessary.

The IGMPv2 Maximum Response Time (MRT) timer is used. The timer is also known as the Query Response Interval. When any host receives an IGMPv2 Query, it picks a random time between 0 and the MRT to send a Host Membership report. However, if the host hears another host send a report for the group, it does not send a report of its own.

To immediately signal to a router that the host wishes to receive traffic for a particular multicast group, without having to wait for the router to send its periodic Host Membership Query message.

When an IGMPv2 host leaves a group, it sends a Leave Group message. When the IGMPv2 router receives the message, it immediately sends a Group-Specific Query message for that group to determine if there are any remaining hosts that wish to receive traffic.

224.0.0.2, All Multicast Routers

True

When IGMPv2 routers start, they send a General Query to 224.0.0.1. When a router receives a General Query, it compares the source IP with its own, and the router with the lowest IP on the subnet is elected the Querier.

255 seconds

A time period during which, if an IGMPv2 host does not receive an IGMPv1 Query, the IGMPv2 host concludes that there are no IGMPv1 routers present and starts sending IGMPv2 messages.

IGMPv3 Source-Specific Multicast (SSM)

224.0.0.22 (IGMPv3)

The MRT field of the IGMPv1 Query is 0, whereas the IGMPv2 MRT field is nonzero.

It marks its interface as IGMPv1 and stops sending IGMPv2 messages.

The host starts a 400-second Version 1 Router Present Timeout timer, which is reset whenever an IGMPv1 Query is received. If the timer expires, there are no longer any IGMPv1 routers present on the subnet, and the IGMPv2 host starts sending IGMPv2 messages.

The IGMPv2 router receives an IGMPv1 Report message (type 0x12), and changes its behavior to accommodate the IGMPv1 host(s).

The IGMPv2 router ignores Leave messages and the Group-Specific Queries triggered by receipt of the Leave messages.

Equal to the Group Membership Interval, which is 180 seconds by default for IGMPv1.

The switch listens for the following routing protocol messages:

The port is added to the port list of all Group Destination Addresses in the CAM table for that particular VLAN.

The switch creates an entry in the CAM table for the Group Destination Address and adds the host port and router port to it.

The switch removes the host port from the Group Destination Address CAM table entry. The switch then sends the Leave message to the router, unless there are more host ports in the GDA CAM entry, in which case the switch discards the Leave message.

True

Globally: no ip igmp snooping vlan vlan

True, it is not a standalone feature.

True

IGMP filters are typically used on access switches connected to end-user devices.

IGMP group/channel access control

To enable hosts that are not directly connected to a downstream device to join a multicast group sourced from an upstream network (such as with UniDirectional Link Routing).

Reverse Path Forwarding (RPF) check

The router looks at the source IP of the multicast packet, and if the route to the source is on the interface where the multicast packet was received, the packet passes the RPF check and is forwarded, otherwise it is dropped.

The multicast packet is dropped at the RP until a multicast host has joined the particular group.

The downstream routers check the reverse path to the RP, not the source.

The router compares the TTL value on the multicast packet with the configured TTL value on each outgoing interface (whose default is 0). If the configured TTL value is less than or equal to the TTL present in the multicast packet, the packet is forwarded.

0

The configured TTL threshold value on an interface applies to all multicast packets, and therefore does not allow for per-group flexibility. 

Administratively-scoped multicast addresses are those in the 239.0.0.0/8 range. Administrative scoping works by configuring and applying a filter on the router's interface so that multicast addresses in the administratively-scoped range are not allowed to enter or exit the interface.

PIM-DM

30 seconds

224.0.0.13

Neighbors are discovered, and adjacencies are established and maintained by receiving PIMv2 Hellos on PIM-enabled interfaces.

Only when it has an active PIMv2 neighbor on the interface, which is established by receiving a PIM Hello message from the neighbor.

Source-based distribution tree

(S,G)

The PIM Prune message is sent from one router to a second router to cause the second router to remove the link on which the Prune is received from a particular (S,G) SPT.

Upon receipt of multicast packets on a non-RPF interface.

The connected device is the source of the particular multicast group.

A Prune message is actually a Join/Prune message with a group address listed in the Prune field, and a Join has a group message in the Join field.

The router finds the matching (S,G) SPT entry and marks the interface on which the Prune message was received as "pruned" and starts a Prune timer (whose default is 3 minutes). When the timer expires, the interface is placed into a forwarding state.

When a PIM-DM link is pruned, it will begin flooding again after 3 minutes by default. The PIM-DM State Refresh message is sent upstream by pruned routers every 60 seconds by default to reset the 3-minute timer and prevent PIM-DM from flooding traffic on the link.

False: PIM-DM State Refresh messages are sent on pruned links every 60 seconds by default, but are not dependent on the 3-minute (default) Prune timer.

A Graft message is sent by the downstream router to the upstream router to request the multicast traffic again for the particular (S,G).

When the upstream router receives the Prune, because it was received on a multiaccess network (as opposed to point-to-point), it sets a 3-second timer. The other router(s) on the segement must sent a Prune Override message (which is actually just a normal Join message) before the timer expires. 

When multiple multicast routers are present on a network segment, the PIM Assert process is used to determine which router should be the one to forward the multicast traffic based on which router has a better metric to the multicast source.

The routers on the multiaccess network segment receive each other's PIM Assert message, which contains the AD and metric the router used to reach the multicast source. The forwarder is chosen by:

The DR is elected by receipt of PIM Hello messages. The PIM router with the highest IP address becomes the DR for the link.

IGMPv1 does not have a mechanism to elect a querier, so the PIM DR is used as the IGMPv1 Querier.

The winner of the Assert is responsible for forwarding multicast traffic for the particular multicast group onto the LAN.

Globally: ip pim rp-address ip

The first-hop multicast router attempts to register the group with the RP, but since no receivers for the group have registered with the RP, the RP sends a Register-Stop message back to the first-hop multicast router.

The first multicast packet is encapsulated in the Register message in case the RP has interested receivers registered with the group.

The router starts a 1-minute Register-Suppression timer, and does not send any further Register messages to the RP until five seconds before the timer expires, when it then sends a Register message with the Null-Register bit set. 

When the router receives a PIM Join message on any interface other than the one used to route packets toward the RP

The tree with the RP at the root that defines over which links multicasts should be forwarded to reach all required routers.

To allow a router to inform the RP that it has a local source for a particular multicast group

Shortest Path Tree / Source-Based Tree / Source Tree

Root Path Tree / Shared Distribution Tree

The RP joins the SPT (S,G) toward the multicast source, and sends a Register-Stop message to the source's first-hop router so that it stops sending multicast-encapsulated packets within unicast Register messages.

PIM Join. If the router does not send a PIM Join within the default timeout of 3 minutes, the upstream router's interface reverts to being pruned.

Every 60 seconds

Shortest Path Tree

Cisco routers switch over from the RPT to the source-specific SPT after they receive the first packet from the shared tree, by default.

Global: ip pim spt-threshold kbps

Downstream routers do not know the IP address of the multicast source (only the IP address of the RP) until they receive the first multicast packet for the group from the source.

The presence of the "J" flag.

The router sends a Prune for the (S,G) to the RP with the RP-Tree bit set, which indicates to the RP (and to the upstream routers toward the RP) that the router has switched over to the SPT and no longer needs the traffic from the RPT.

Statically with ip pim rp-address

Anycast RP using MSDP

The RP sends RP-Announce messages to 224.0.1.39 stating that the router is an RP, and the particular multicast groups the RP handles.

False: The Auto-RP Mapping Agent can be a different router than the RP, but they are usually configured on the same router.

The mapping agent learns all the RPs and the multicast groups they support, then multicasts RP-Discovery messages that identify the RP for each range of multicast group addresses.

224.0.1.40

By listening to RP-Announce messages from multicast group 224.0.1.39 sent by the RP.

When multiple RPs are present and serve as RP for the same groups, the Mapping Agent advertises the RP with the highest IP address as the current RP for the particular multicast group.

RP-Discovery 224.0.1.40

Sparse-dense-mode allows an interface to use multicast sparse or dense mode, depending on the particular group.

The global ip pim autorp listener command joins the Auto-RP multicast groups 224.0.1.39 and 224.0.1.40 in dense-mode in order to discover the RP. After the RP is discovered, sparse-mode communications can take place.

Globally:

Globally:

False: Boostrap messages are flooded only on non-RPF interfaces. Likewise, loops are prevented because Boostrap messages are discarded when received on non-RPF interfaces.

Boostrap messages are discarded when received on non-RPF interfaces.

The BSR is similar to the Auto-RP Mapping Agent.

False: Unlike Auto-RP, BSR sends all group-to-RP mapping information to the other PIM routers, and they independently choose the currently best RP for each multicast group by running the same hash algorithm on the information in the bootstrap message.

The BSR floods all mapping information in Boostrap messages to the All-PIM-Routers address 224.0.0.13.

When BSR is used, all PIM routers already know the unicast IP address of the BSR from the earlier receipt of Boostrap messages. Candidate RPs send unicast c-RP Advertisements to the BSR which include the IP address used by the c-RP and the groups it supports.

True: Each Candidate-BSR sends Bootstrap messages that include the priority of the BSR and its IP address. The highest priority wins (default 0), followed by highest IP address.

0, higher priority preferred.

Globally:

Globally:

With Anycast RP, RP redundancy and load sharing can be achieved with multiple RPs concurrently acting as the RP for the same group. 

Multiple RPs share the load for a single multicast group

Multiple RPs are configured with the same IP address, cover the same multicast groups, and are advertised into the IGP. All the RPs act as normal, and the same information is distributed either statically, with Auto-RP, or with BSR. All routers use the closest RP based on their unicast routing table.

Globally:

To provide a method for RPs in different multicast domains to register multicast sources with peer RPs.

Source Active (SA) messages list the IP addresses of each source for each multicast group.

Every 60 seconds

Each of their MSDP peers, as well as to the multicast sources

False: RPs can send Source-Active (SA) request messages. The MSDP peers respond with SA response messages.

-RP builds a shared tree with itself as the root

Normally, PIM-SM uses the shared tree created to the RP to initialize multicast traffic, with both the RP and the receivers eventually joining the SPT to the source.

When most of the receivers are also senders, such as videoconferencing.

The sender's first-hop router forwards the traffic up the shared tree to the RP. The RP then forwards the traffic back down the shared tree to all of the leaf routers containing the receivers.

Globally:

show ip pim rp mapping will reveal which groups, if any, are using PIM BiDir.

30 seconds

Globally:

SSM receivers know the unicast IP address of the source, and specify it when they join the multicast group. SSM receivers join a specific (S,G).

Without SSM, multicast receivers receive all traffic sent to a particular subscribed multicast group. With SSM, multicast traffic is received only from the specified source on the particular multicast group.

True. SSM only uses SPT and hosts join a specific (S,G) which negates the requirement of RPs and shared trees.

The default keyword means that the range 232.0.0.0/8 is used for SSM.

IGMPv1 and IGMPv2 do not allow receivers to explicitly specify sources in order to build SPTs.

Globally:

False: PIMv6 is enabled automatically for all IPv6-enabled interfaces when ipv6 multicast-routing is issued.

Interface:

Interface:

True. IPv6 multicast operates only in sparse-mode, and the RP must either be statically defined, use IPv6 BSR, or Embedded RP.

Globally:

Globally:

Globally:

MLD is comparable to IGMP.

Query

Done

Embedded RP enables the identity of the RP to be embedded as part of the multicast group address.

Embedded RP addresses always being with FF70::/12

Scope

Interface:

The IP Precedence (IPP) field

0 Routine

Bits 0 - 5 are the DSCP

Class Selector PHBs

AFxy where x = 1 - 4 and y = 1 - 3. Higher values of x get better queuing treatment, and higher values of y have a higher probability of being dropped.

8x + 2y = decimal

46

False: it is present only when the Ethernet frame includes an 802.1Q tag, or an ISL trunking header.

On ingress only, and only if the interface supports that particular header field.

On egress only, and only if the interface supports that particular header field.

NBAR

The packets would not be marked, and will retain their existing DSCP values.

match-all  (logical AND)

No packets are matched because a packet cannot be marked as DSCP 0 and DSCP 1 simultaneously.

It is matched to the special class class-default

Without the ip keyword, both IPv4 and IPv6 packets are marked.

Interface: load-interval

Copy the PLDM file to the router, then configure globally:

Mark as close as possible to the source, but not from untrusted devices.

5 / 5 / EF

4 / 4 / AF41

3 / 3 / CS3

3 / 3 / AF31,AF32,AF33

2 / 2 / AF21,AF22,AF23

1 / 1 / AF11,AF12,AF13

0 / 0 / BE

0 / 0 / 2,4,6

Traffic rate measured in bps

True - however, features like NBAR are broken when working with encapsulated traffic.

QoS pre-classification permits routers to make egress QoS decisions based on the original traffic before encapsulation.

With the qos pre-classify command under the tunnel interface, virtual template interface, or IPsec crypto map.

AutoQoS for VoIP

auto qos voip {cisco-phone | cisco-soft-phone}

All traffic is marked as DSCP 0 and treated as best effort, which is the default behavior for a normal trunk port.

Voice/Video traffic

QoS enabled globally

The router changes the encapsulation to PPP, creates a PPP Multilink interface, and enables LFI on the interface.

With the trust keyword, the router creates class maps that group traffic based on DSCP values, associates the class maps to a policy map, and assigns the policy map to the interface.

Fancy queuing

FIFO

True

True

True

Short hardware queue lengths mean packets are more likely to be in the controllable software queues, giving the software queuing more control of the traffic leaving the interface.

The queue length

Classification

Drop policy

Scheduling

LLQ prevents the high-priority queue from starving other queues with policing.

64 queues/classes

class-default

True

True

Explicit

By using the bandwidth command within a class map.

By using the priority command within a class map.

20 percent of the configured bandwidth

The class will say "Strict Priority"

LLQ places packets from multiple LLQs into a single internal LLQ. Packets in the different LLQs get scheduled ahead of nonpriority queues, but are serviced based on arrival time for all packets in any of the PQs.

Each LLQ can have different policer settings. One use case is for sending both voice and video. Each traffic class can be placed into its own LLQ, but be individually policed so that neither traffic class overruns the other.

True

Only when there is congestion, which occurs when the hardware queue is full. 

When a queue is full, there is no place to put newly arriving packets, so they are discarded.

The WRED full drop occurs when the average queue depth rises above the configured maximum threshold, and all new packets are discarded. However, the actual queue might not be full.

The average queue depth

The MPD is the calculated discard percentage used at the maximum threshold based on 1/MPD.

Minimum threshold

Physical interfaces (with FIFO queuing)

With the random-detect keyword either under a physical interface or in a non-LLQ class in a policy map.

Without the dscp-based keyword, WRED uses IP Precedence.

After issuing the random-detect or random-detect dscp-based command, issue either random-detect precedence or random-detect dscp

MDRR is used in place of CBWFQ and LLQ on the Cisco 12000 series router platform, because it does not support CBWFQ and LLQ.

seven round-robin queues (0 - 6) plus one PQ

Strict priority mode serves the PQ whenever traffic is present in the queue, which can lead to starvation of the other queues.

The Quantum Value is the number of bytes the queue holds. The Deficit Count is the number of bytes beyond the QV that were transmitted in a single round-robin pass.

Two, either of which (but not both) can be configured as a PQ

Shared Round Robin (SRR)

CoS 5

90% for queue 1

Weighted Tail Drop (WTD), which allows configuration per-queue

Four

The frame's internal DSCP is compared to a global DSCP-to-CoS map to determine a CoS value

Both help to prevent queue starvation when a PQ exists, but shaped round-robin also rate-limits the queues so that they do not exceed the configured percentage of the link's bandwidth.

Globally:

Per-interface:

The shaped scheduler never allows any queue, PQ or non-PQ, to exceed its configured percentage of link bandwidth, even if that means the link sits idle.

True. Two reservations must be made, from source to destination, and from the destination back to the source.

Direction, flow

Destination IP address

The RSVP messages appear as ordinary IP packets to non-RSVP-capable routers.

The first RSVP-capable router in the path from source to destination sends an RSVP PATH message toward the destination IP address.

It replies with a RESV message requesting the necessary QoS.

The failing RSVP router discards the received RESV message requesting the particular QoS, and returns an error message.

The originating router will receive back a RESV message that has traveled the entire path between source and destination RSVP routers.

Receipt of a RESV message means the reservation was successful, and the originating router sends back a RESV message in response to the destination router's PATH message to secure QoS in both directions.

The destination RSVP router responds with a ResvConf message, which confirms the reservation.

Interface:

False. Transit routers do not require RSVP to be enabled, and RSVP messages are forwarded as any other ordinary IP packet.

The packets are delayed and held in a shaping queue.

Tc, which is measured in milliseconds

Committed burst (Bc)

The CIR defines the rate for a VC based on a business contract

Burst excess (Be)

Tc = Bc / CIR (shaping rate)

The bucket size is the Bc, and at the beginning of each Tc, the token bucket is refilled.

The packet must wait until the next Tc (when new tokens are added to the bucket) to acquire enough tokens for the packet to be sent.

Be (excess burst) makes the single token bucket bigger, but there will still only be the Bc (committed burst) number of tokens added at the beginning of each Tc (time interval).

Generic Traffic Shaping

Identify the traffic in a class-map

Bc = 8000 bits

Bc = Tc (25 ms) * shaping rate

It does not inherit the bandwidth setting of the physical serial interface, it defaults to 1544.

Both calculate Bc, Be, and Tc the same way

Committed Access Rate

Conforming

Single-rate, two-color

bits

Tokens are replenished at the policing rate. 

Single-rate, two-color policing uses a single Bc bucket and supports conform and exceed actions.

When the size of the packet requiring transmission is equal to or less than the number of tokens available in the Bc bucket.

When the size of the packet requiring transmission is greater than the number of tokens available in the Bc token bucket.

When the size of the packet requiring transmission is equal to or less than the number of tokens available in the Bc bucket.

When the size of the packet requiring transmission is greater than the number of tokens available in the Bc bucket, but less than or equal to the number of tokens available in the Be bucket.

When the size of the packet requiring transmission is greater than the number of tokens available in both the Bc and Be buckets.

Committed Information Rate (CIR)

The Bc bucket is replenished at the CIR, and the Be bucket is replenished at the PIR.

With the police command inside a policy-map

The single-rate, three-color configuration must either set a violate action, or explicitly set the Be to something larger than 0.

The number of bytes that could be sent in 1/4 second at the defined policing rate.

Multi-action policing

When configuring the police statement, do not enter any actions. When you enter the command without actions, you are placed into the policing subconfiguration mode, where you can configure multiple actions.

The police command uses the percent keyword for CIR and PIR, the Bc and Be values use the ms (milliseconds) keyword.

single-rate, two-color

CAR is configured with the rate-limit command under an interface.

Configure the first rate-limit statement with conform-action continue which causes all conforming packets to be evaluated by subsequent rate-limit statements.

10ms

Interface:

HDLC

Cisco's version of HDLC includes a 2-byte Type field for multiprotocol support.

On the DCE end: clockrate

PPP includes a standardized Protocol field in the same location as the Cisco HDLC Type field. PPP also includes padding in the Data field to ensure the frame has an even number of bytes.

Link Control Protocol (LCP) controls the features independent of any specific Layer 3 protocol

Link Quality Monitoring (link is dropped if a percentage of frames have errors)

Interface: ppp quality

Each frame is fragmented by the number of links in the bundle, and sent across all links equally.

Create a multilink interface, enable multilink, and assign a group:

LFI prevents small, delay-sensitive packets from having to wait on longer, delay-insensitive packets to be completely serialized out an interface.

Interface: ppp multilink interleave

Interface: ppp multilink fragment-delay x

Layer 2 payload

Interface: compress

When the average payload is small.

PPPoE provides an emulated (and optionally authenticated) point-to-point link across a shared medium.

Create a Broadband Aggregation Group to handle the incoming PPPoE connections and bind it to a virtual template interface:

Under the bba-group:

The PPP header adds 8 bytes of overhead to each frame.

Under the virtual-template interface:

Create a BBA group and assign a virtual template

Configure a dialer interface

With the login statement under the console, aux, or VTY line.

With the password statement under the console, AUX, or VTY line.

With the global service password-encryption statement.

Individual existing passwords remain encrypted until they are changed.

False: The enable secret password is not affected by service password-encryption and is always encrypted with MD5.

UDP 1812

TCP 49

False: the first configured reachable method is used as long as there is a response of either accepting or rejecting the user.

UDP 1646

If the login statement was configured, it is removed. However, the password statement remains, and is used if the login authentication method is set to line.

default refers to the default authentication list. Named authentication lists are also supported. 

The method is what is used to validate the AAA function, authentication in this case.

group refers to groups of AAA servers, including named lists, all LDAP servers, all RADIUS servers, and all TACACS+ servers.

UDP 1645

Configure the global AAA authentication statement with a user-defined list name:

no cdp run disables CDP globally for the device

Static configuration of the allowed MAC addresses

1

protect silently implements the port security

False: While sticky-learned MAC addresses are added to the running configuration, the configuration must be saved before a reload.

Globally:

Interface:

If an ARP reply has a source address that was not DHCP-assigned to a device off that port, the ARP reply is filtered by DAI.

Globally:

The static keyword means ARP messages are denied unless explicitly permitted by the ACL. Without the static keyword, if the ARP message does not match the ACL, it is then checked against DHCP bindings.

Globally:

Globally:

False. DAI can use the DHCP snooping binding database, in which case DHCP snooping must first be enabled, however DAI does not require DHCP snooping to be enabled when using static ARP ACLs.

Dynamic ARP Inspection

DHCP snooping filters messages sent by only by DHCP servers (not DHCP clients) on untrusted ports, because a DHCP server should never reside on an untrusted port.

DHCP release and decline messages on untrusted ports are checked against the DHCP snooping binding database. The messages are dropped if the IP address in the messages is not associated with the bound port.

Globally:

Interface:

Privileged EXEC mode:

Interface:

IP Source Guard uses either the DHCP snooping database or static bindings to permit incoming packets only from bound IP addresses (and optionally IP + MAC). The helps mitigate IP spoofing.

Interface:

Globally:

True: IOS will accept all IP Source Guard configuration commands, including those for static bindings, but will not become active until DHCP snooping is enabled.

EAPoL: Extensible Authentication Protocol over LAN

The authenticator (typically a switch) translates between EAPoL frames between itself and the supplicant, and the RADIUS messages required by the authentication server. The authenticator also enables/disables ports based on the success/failure of authentication.

Globally:

CDP, STP, and EAPoL

You can use the regular Storm Control configuration commands on EtherChannel interfaces, but the commands have no effect. Storm Control can be enabled only on physical ports.

Storm Control can limit individually broadcast, multicast, and unicast traffic per-port.

Interface:

Interface:

1-99 and 1300-1999

100-199 and 2000-2699

The 0 bits must match, and the 1 bits are "don't care"

255.255.255.255 - subnet mask

A directed broadcast address

This prevents the router from forwarding broadcasts onto the network segment from a different segment. 

uRPF is a security feature that checks the source IP address of incoming packets and will discard them if the source IP is not reachable on the incoming interface (strict mode) or if it is not reachable via any interface (loose mode).

Whether uRPF strict or loose mode is configured, the default behavior is to not verify the uRPF check against the default route. The allow-default keyword allows the router's default route to be used in determining the validity of the packet.

Both trigger IP directed broadcasts. Smurf uses ICMP Echo, Fraggle uses UDP Echo.

TCP Intercept monitors TCP connections for SYN attacks.

Globally:

show tcp intercept {connections | statistics}

ARP

ACLs

Malicious traffic should be placed at the top so that it is dropped immediately.

Tunnel interface:

Tunnel interface:

Tunnel interface:

On the DMVPN Tunnel Interface, ip nrhp network-id id enables NHRP, which is critical to the operation of DMVPN. All routers and interfaces configured with the same ID belong to the same DMVPN.

Tunnel interface:

Tunnel interface:

Lower the MTU on the tunnel interface to account for overhead:

Tunnel interface:

Create the ISAKMP policy

Globally:

Globally:

Tunnel interface:

Router discovery

Public/private key pairs

Globally create the policy to define the role:

client

To track IPv6 host liveness so the neighbor table can be immediately updated when an IPv6 host disappears to revoke network access privileges as they become inactive.

Globally:

If its IPv6-to-MAC mapping is verifiable

IPv6 ND Inspection learns and secures bindings for SLAAC addresses in L2 neighbor tables. IPv6 ND Inspection analyzes ND messages to build a trusted binding table database, and ND messages that do not conform are dropped.

Globally create a policy:

The IPv6 binding table must be populated with IPv6 prefixes for IPv6 Source Guard to work.

The IPv6 address glean feature is notified so it can try to recover the traffic by querying the DHCP server or by using IPv6 ND.

Globally define the policy:

PACLs take precedence. Any traffic allowed by a PACL will then be evaluated by a VACL.

Create an IP or MAC ACL

Spokes can be added without changing configuration on the hub router.

Tunnel interface:

Phase 1 only permits hub-to-spoke and spoke-to-hub traffic.

Tunnel interface:

Tunnel interface:

Automatic 6to4 tunnel border router

One

IPv6 subnet 2002::/16 is reserved for 6to4 addressing. The full IPv6 prefix is derived from the border router's external-facing IPv4 address encoded as hexadecimal. Using the example 10.1.100.1, the prefix is 2002:0a01:6401::/64.

115

Each CE is its own root, and therefore the STP root does not change when multiple sites are connected.

To allow more than two devices to exchange traffic securely without requiring a high number of SAs.

The KS is used to create, maintain, and send a policy to Group Members, which provides information as to what traffic should be encrypted by the GM and how it should be encrypted.

The TEK is generated by the Key Server (KS) and is used by the Group Members (GMs) to encrypt the data.

The Key Server (KS) generates the KEK which is used to encrypt information between the KS and the Group Members (GMs).

GET VPN does not set up any IPsec tunnels between Group Members (GMs). Every GM has the policy (what to encrypt and how) and encrypts every packet that conforms to the policy and sends it to the network using Encapsulated Security Payload (ESP), using original IP addresses for routing the packets.

The Key Server (KS) must send out a new Transport Encryption Key (TEK) and Key Encryption Key (KEK) to the Group Members (GMs) before the TEK expires, which is 3600 seconds by default.

ISAKMP GDOI (Group Domain of Interpretation)

The RIB has an entry for each destination prefix containing the next-hop IP address. The CEF FIB goes a step beyond and maintains an adjacency table containing the Layer 2 header of the outgoing interface per destination prefix. 

The ingress PE's FIB knows to push the appropriate label onto the packet for the destination and forward it out the correct interface. The upstream P router receives the labeled packet, and uses its LFIB to forward the packet out the correct interface. The egress PE router receives the labeled packet, and its LFIB knows to pop the label and forward the packet unlabeled to the CE.

20-bit label

When an IP packet arrives at the ingress PE, the IP packet's TTL value is copied into the MPLS header's TTL field. As the MPLS packet traverses the MPLS network, the TTL field in the MPLS header is decremented at each hop. When the packet arrives at the egress PE and the label is removed, the MPLS TTL is copied back into the IP packet's TTL field.

Interface:

Routers running LDP multicast Hellos to 224.0.0.2 via UDP 646.

The LDP neighbor with the highest LDP ID.

-Manually configured

An RD is 8 bytes

Left side: ASN or IPv4 address

One RD

As BGP Extended Communities

False: RDs make all prefixes unique, while RTs act as a "tag" for VRFs, and can be different from the RD value. 

VRFs can have a RT export value assigned to them, which tags the routes as BGP extended communities as they are redistributed on the PE into the iBGP table. VRFs on other PE routers can import the same RT value so that the routes are redistributed from the iBGP table back into the VRF routing table.

VRFs can both export and import multiple RTs.

The IP address is removed and must be reapplied.

Globally:

ip vrf specifies an IPv4-only VRF, whereas vrf definition specifies a multiprotocol VRF.

Interface:

IOS automatically creates two lines of configuration:

Under the routing protocol's VRF configuration submode.

You cannot enter BGP configuration mode for the particular VRF if it does not first have an RD configured.

PE router:

Redistribution configuration on the PE is not required, unlike with IGPs and static routing.

The inner label in an MPLS label stack that identifies the outgoing interface the egress PE should use to forward the unlabeled packet.

False: A PE router only has one LFIB table, regardless of the number of configured VRFs.

The second-to-last router in the LSP pops the outer label so that the egress PE does not have to perform two lookups - one for the outer label, and one for the VPN label.

A set of packets that are forwarded along the same path and receive the same forwarding treatment.

An interface can only be associated with a single VRF, therefore subinterfaces must be used.

AS_PATH

The router rejects the request

BGP Open

After BGP Open messages have been exchanged.

60 seconds

180 seconds

BGP process:

-Manually configured router-id

By default the IP address of the outgoing interface used to reach the neighbor IP address is used.

The destination address is explicitly configured with the BGP neighbor ip-address statement.

Disabled by default in newer IOS versions.

Whenever there is more than one route through which the BGP router can reach a peer.

With synchronization enabled, BGP will not advertise a route to an external neighbor unless the route is local or exists in an IGP.

BGP process:

BGP:

The router must receive a TCP connection request with a source address that the router finds in a BGP neighbor statement

The neighbors both use the lower values of each of the two timers. Mismatched settings do not prevent neighborship.

Idle > Connect > Active > OpenSent > OpenConfirm > Established

BGP is enabled on a router, but neighbor statements have not yet been configured and therefore the router is not listening for TCP connections for BGP.

The BGP routing process detects that a peer is trying to establish a TCP session.

The BGP routing process is trying to establish a TCP session with a neighbor.

Open

Establishing neighbor relationships and exchanging basic parameters

To maintain neighbor relationships. The relationship is reset if a keepalive message is not received within the negotiated hold time.

To exchange NLRI

Notification is sent (with FSM error code) if an error or configuration change affects the peering session

The peering session is reset and must be re-established.

BGP process:

The route referenced in the network statement must be in the current IP routing table. If the route does not exist, it is removed from the BGP RIB.

The default classful mask is assumed.

If any subnets of a classful network would be redistributed, only the classful network is redistributed.

If a network command lists a classful network number, with the classful default mask (or no mask), and any subnets of the classful network exist, inject a route for the classful network.

AS_SEQ

If the component subnets of the summary route have different AS_SEQ values, the router uses a null AS_SEQ.

BGP process:

BGP process:

True

The aggregating router removes the summary and notifies its neighbors by withdawing the route.

The local BGP table lists the next hop as 0.0.0.0

False. The AS_SET is generated only if the AS_SEQ is null. If the AS_SEQ values of all the component subnets are identical, the AS_SET PA is not generated because the AS_SEQ will be that of the component subnets.

All component subnets advertised along with the summary

network command

A default route can be injected into BGP with the network 0.0.0.0 BGP command, as long as a route to 0.0.0.0/0 exists in the IP routing table (through any means).

When you use the redistribute command under the BGP process, all matched routes in the current IP routing table are redistributed, with the exception of the default route.

None: this command does not add a default route to the local BGP table, and it does not check for the existence of a default route in the IP routing table by default.

BGP process:

Incomplete

IGP

IGP if all component subnets also carry the IGP ORIGIN code

Withdrawn routes

Update messages contain NLRI only for those that share the exact same Path Attributes and PA values.

The current BGP table.

BGP will advertise only the single best route from all that are available in the BGP table to a neighbor.

Routes that are not considered best

Shortest AS_PATH

The NEXT_HOP must be 0.0.0.0 as the result of the route being injected on the local router

Do not change the NEXT_HOP PA value by default when advertising to an iBGP neighbor

Change the NEXT_HOP value to the update source IP address.

BGP process:

BGP process:

BGP process:

routes displays all routes that have been received AND accepted

Make the eBGP neighbor's IP address reachabile by advertising it's subnet into the IGP

The eBGP route in the BGP table must be considered "best"

eBGP (default 20)

BGP process:

BGP process:

The neighbor-ip represents the IP address used on the BGP neighbor statment. The acl examines routes received from the particular neighbor, and assigns the AD for any routes matching the ACL with a permit action.

The route entered into the IP routing table contains the exact same prefix, length, and next-hop IP address as listed in the BGP table, even if the NEXT_HOP PA is an IP address that is not in a connected network.

BGP process:

When the same prefix is learned from eBGP and an IGP, the eBGP prefix is preferred, even though the IGP prefix may actually be the better path. The BGP network network backdoor command causes that specific network to use the BGP Local AD (200 by default) and no longer advertises the route with BGP.

BGP synchronization resolves routing black holes for internal transit routers between iBGP peers. BGP synchronization says to not consider an iBGP route in the BGP table as best unless the exact prefix was learned through an IGP and is currently in the routing table. This means BGP routers need to redistribute their learned prefixes into the IGP so that traffic is not blackholed on transit routers, and BGP routers cannot advertise unreachable prefixes.

BGP synchronization requires BGP-learned routes to be redistributed into the IGP before they can be advertised by an iBGP peer. As the Internet BGP table has grown, it is now infeasible to redistribute all of the routes into the IGP, so synchronization is disabled by default now.

BGP does not allow the OSPF-learned route to be considered best if the OSPF RID of the router advertising the prefix is different from the BGP router advertising the same prefix.

Create a full mesh of iBGP peerings

64512 - 65535

BGP process:

True. Within a confederation sub-AS, full iBGP rules are in effect.

True: If peering between loopbacks, you must adjust the neighbor ip ebgp-multihop ttl value.

False: Confederation eBGP connections work like iBGP connections in that the NEXT_HOP is not changed by default.

True

Confederation routers remove the confederation ASNs from the AS_PATH in Updates sent outside the confederation.

BGP process:

False. Only the RR changes its BGP behavior. Both clients and non-clients do not change their behavior and are not even aware of the RR.

Prefixes learned from non-clients are not advertised to other non-clients (normal iBGP peering rules).

One or more

False: One RR from each cluster must be peered with at least one RR from all clusters. However, it is typical to create a full mesh of peerings between all RRs across all clusters.

True. Normal iBGP advertisement rules are in place between RRs and non-clients, therefore a full mesh of iBGP peerings between RRs and non-clients should be expected.

Only advertise best routes.

Route Reflectors add their cluster ID into the CLUSTER_LIST PA before sending an Update. When receiving a BGP Update, RRs discard received prefixes for which their cluster ID already appears.

The ORIGINATOR_ID PA lists the RID of the first iBGP peer to advertise a route into the AS. If a router sees its own RID as the ORIGINATOR_ID in a received route, it does not use or propagate the route.

The default is the RID. The cluster ID can be manually configured under the BGP process:

Configuration is performed on the RR under the BGP process:

Cluster list in show ip bgp prefix

MP_REACH_NLRI

BGP process:

Well-known Mandatory

Well-known Mandatory

Optional Transitive

Well-known Discretionary

Well-known Mandatory

Optional Nontransitive

Optional nontransitive

Create an ACL denying the specific routes, and ending with permit ip any any

Create a prefix list that denies the specific routes, and ends with permit 0.0.0.0/0 le 32

route-map deny means the matched NLRI is filtered

ACL permit statements match the route-map clause, while ACL deny statements do not match the route-map clause.

True. BGP must be reconfigured to support soft reconfiguration for inbound Updates, though, with the BGP command neighbor ip soft-reconfiguration inbound

To support soft-reconfiguration inbound, BGP must keep a copy of all of the received Updates from a neighbor, instead of just those that are entered into the BGP table after policies have been applied. This takes up extra memory, which is why it is disabled by default.

Prefixes that are matched by a route-map permit action will not be advertised with the BGP summary address.

ip as-path access-list num {permit | deny} regex

-The regex in the first line in the AS_PATH ACL is applied to the AS_PATH of each route and is passed or filtered based on permit or deny if there is a match

Start of line

End of line

Logical OR applied between preceeding and succeeding characters.

Any delimiter: blank, comma, start of line, end of line

Any single character

Zero or ONE instance of the preceding character

Zero or more instances of the preceding character

One or more instances of the preceding character

Parenthesis combine enclosed string characters as a single entitly when used with ?, *, or +

Creates a wildcard for which any of the single characters in the string can be used to match that position in the AS_PATH

.*

^$

^123$

^123

^123_45$

^123_.*_45$

^123_.*45

Without the parenthesis, the | is applied only to the single characters before and after the |. This is a common mistake.

^{

True: For example, show ip bgp | include 65000_65000 displays BGP routes that have been prepended by 65000 at least twice.

True. You can enter { and } directly into the AS_PATH access list.

False: Cisco IOS uses the order listed in the output of the show ip bgp command when applying regex logic.

Well-known means that the BGP implementation MUST support the PA.

Optional means that the BGP implementation is not required to support the particular path attribute.

Is the NEXT_HOP PA reachable? If not, reject the route from the decision process.

Weight: Cisco-proprietary, higher is better. The administrative weight can be assigned to each NLRI locally on the router, and is not passed on in Update messages.

LOCAL_PREF PA: higher is better. This well-known discretionary PA can be set on a router inside the AS, and is not distributed outside the AS.

Locally-injected routes: choose routes injected locally (via network, redistribution, or summarization) first.

AS_PATH length: shorter is better. This calculation ignores both AS_CONFED_SET and AS_CONFED_SEQ values, and treats an AS_SET as a single ASN, regardless of the number of ASNs within the set.

BGP process:

ORIGIN PA: IGP routes preferred over EGP routes preferred over Incomplete.  I > E > ?

MED: smaller is better

Neighbor type: eBGP preferred over iBGP. Confederation eBGP is treated as iBGP.

IGP metric to reach the NEXT_HOP. Lower is better.

To determine the single best path for each NLRI. 

-Keep the oldest eBGP route (which reduces route flaps)

BGP process:

Weight is a local value and configured per-neighbor.

100, higher is better

BGP process:

BGP process:

If the router attempts to inject routes locally through multiple methods, such as a route injected through both redistribute connected and the network command. By default, both routes would have the same weight and local preference, so the ORIGIN code would be the tiebreaker.

BGP process:

With the neighbor local-as keyword.

With this configuration, BGP communicates with 10.10.10.1 using 50 as its ASN. When the router sends Updates to the neighbor, it prepends 50 100 to each AS_PATH. With the no-prepend keyword, any routes received from the neighbor will not have 50 prepended upon reception, so when this router sends the routes to another neighbor, only 100 will appear in the AS_PATH instead of 50 100.

True, this is accomplished by matching routes and using set origin in a route-map.

True, MED is an optional nontransitive PA.

0

Through the BGP neighbor ip route-map map out command. The route map matches the desired routes and changes the MED with set metric

The default MED value for routes is 0. This command makes the default value 4B. 

True. You can override this behavior with bgp always-compare-med under the BGP process.

By default, Cisco IOS processes BGP table entries from newest (most recently learned) to oldest. When there are multiple routes to the same NLRI, IOS compares the newest two and selects the best, then compares it against the next route and chooses the best of the two, and so on. 

False: With the maximum-paths command, multiple routes can be added to the local IP routing table, but BGP will still only advertise a single "best" route from the BGP table.

Choose the neighbor with the lowest RID among only eBGP sources if there is a mix of iBGP and eBGP sources, otherwise choose the lowest RID if there are only iBGP sources.

The existing best route is kept to avoid route flaps. This behavior can be modified with the BGP command bgp bestpath compare-routerid

The route through the neighbor with the smaller rid is used for iBGP.

The final tiebreaker is the lowest BGP neighbor ID (IP address). This is used when the route is coming from a router who has multiple separate neighbor relationships, as opposed to a single relationship using loopback addresses.

1

-The multiple routes must have made it through the normal BGP "N WLLA OMNI" decision process

-The iBGP routes must have made it through the normal "N WLLA OMNI" bestpath selection process

This command is used to allow more than a single BGP route to be entered into the routing table for both eBGP and iBGP routes, but only for MPLS under BGP address family configuration mode.

False: You must configure under the BGP process neighbor ip send-community [standard | extended | both]

BGP process:

To permit or deny specific community values, which can then be referenced in a route-map.

Create a community-list:

The original community was a 32-bit decimal value, but the new-format is defined by RFC 1997 which is AA:NN where AA is a 16-bit number typically representing an ASN, and NN is an arbitrary 16-bit number.

The first command replaces any existing community values with 10, 20, and 30.

Route-map:

30 seconds

60 seconds by default

eBGP sessions between directly-connected neighbors are torn down the moment the connected subnet between the peers is lost. BGP routes are immediately flushed, and BGP immediately begins looking at alternate routes.

When enabled, BGP monitors the peering session with the specified neighbor, and terminates the BGP session when an adjacency change is detected. A route-map can be referenced to make the fall-over action conditional.

Global:

BGP process:

BGP process:

When component subnets have been filtered with the aggregate-address command, unsuppress-map can be used per-neighbor to re-advertise specific routes that were filtered through summarization.

Create an IP community-list to reference the values to be removed:

1,2 transmit

Fast Link Pulses are detected as part of the autonegotiation process

HDX for 10/100 links

If the port is capable of gigabit or higher speeds, the speed must be set to either 10 or 100. 

Errors and collisions

Collions are detected within the first 64 bytes of a transmitted frame, assuming proper cable lengths.

The Universal/Local bit is the 2nd least-significant bit in the first octet of the MAC address. When toggled, it means that the address has been administratively assigned, overriding the vendor-assigned address. 

The Individual/Group bit is the least-significant bit in the first octet of the MAC address. When toggled, it means the frame is either multicast or broadcast, otherwise it is a unicast frame when not toggled.

Ethernet II / DIX

Ethernet II / DIX

These frame types are typically used by protocols invented by the IEEE, such as STP

Vendor-proprietary Layer 2 protocols like CDP, DTP, VTP, etc.

Across the Ethernet formats, there is a 2-byte field after the Preamble, Destination Address, and Source Address.

This is an Ethernet II format frame, and the value is the EtherType.

This is an 802.2 LLC or SNAP format Ethernet frame, and this field is interpreted as the total length of the 802.2 header + data field, which is a value between 46 and 1500.

SNAP frames have the value 0xAA for both the DSAP and SSAP fields in the LLC header. Any other values indicate that the frame is not in SNAP format.

300 seconds

The original configuration is suspended while the port is acting as a SPAN destination. When the SPAN configuration is removed, the port's original configuration is resumed.

64

True. Only traffic that enters or exits the switch in a source port or VLAN is forwarded in a SPAN session. If the traffic comes from another source within the source (such as routing from another VLAN), that traffic isn't forwarded through SPAN.

RX traffic is transmitted to the SPAN destination before any modification, such as VACL/ACL filtering, QoS modification, policing, etc.)

With the SPAN encapsulation replicate command.

monitor session num {source | destination} remote vlan num

Running the Layer 2 and Layer 3 control protocols for the switching modules on both switches, as well as providing management functions for the VSS including module Online Insertion and Removal (OIR) and the console interface.

Up to 8

True

256

-Configure the switch virtual domain id and switch {1 | 2} on both switches

Globally:

False: The VSL requires unique port channel values on each switch (e.g. po10 on one, po20 on the other).

The VSS will come up in Route Processor Redundancy mode. To avoid this, the port channel numbers on each switch must be unique and must be available.

Up/Down

The prompt will be:

show switch virtual link [port-channel]

The FFM provides a set of APIs used to manage the control plane processes, and the FFM programs the data plane through the FED and maintains all forwarding states for the system.

IEEE 802.3u

IEEE 802.3z

IEEE 802.3ab

Store-and-forward switching fully receives all bits in a frame and checks against the FCS for errors before forwarding a frame.

Fragment-free switching performs like cut-through, but the switch waits for the first 64 bytes of the frame to be received because Ethernet collisions should be detected within the first 64 bytes of the frame.

4 Mbps Token Ring

16 Mbps Token Ring