Cisco (200-301) Exam Questions And Answers page 37

Issuing the switchport port-security mac-address sticky command will allow a switch to save a dynamically learned MAC address in the running-configuration of the switch, which prevents the administrator from having to document or configure specific MAC addresses. Once the approved MAC addresses have all been learned, the network administrator simply saves the running-configuration file to NVRAM with the copy running-config startup-config command.
Switches dynamically build MAC address tables in RAM, which allow the switch to forward incoming frames to the correct target port. By default, an unlimited number of MAC addresses can be learned on a single switch port, whether it is configured as an access port or a trunk port. Switch ports can be secured by defining one or more specific MAC addresses that should be allowed to connect, and by defining violation policies (such as disabling the port) if additional hosts try to gain a connection. The following command secures a switch by manually defining an allowed MAC address:
switch(config-if)# switchport port-security mac-address 00C0.35F0.8301

This command statically defines the MAC address of 00c0.35F0.8301 as an allowed host on the switch port. Manually configuring all of your switch ports in this way, however, would require documenting all of your existing MAC addresses and configuring them specifically per switch port, which could be an extremely time-consuming task.
An example of the use of the switchport port-security mac-address sticky command is shown below:
Switch(config)#interface fastethernet0/16
Switch(config-if)#switchport port-security
Switch(config-if)#switchport port-security mac-address sticky
Switch(config-if)#switchport port-security maximum 1

With the above configuration, if a computer with a MAC address of 0000.00bb.bbbb were plugged into the switch, the following two things would occur:
• Only the host with MAC address 000.00bb.bbbb will be allowed to transmit on the port. This is a result of the port-security mac-address-sticky command, which instructs the switch to learn the next MAC address it sees on the port, and of the port-security maximum 1 command, which further instructs the switch that the address learned is the only address allowed on the port.
• All frames arriving at the switch with a destination address of 0000.00bb.bbb will be forwarded out on Fa0/16.
The switchport port-security mac-address sticky command can also be used in combination with the interface-range command to make every port on the switch behave in this fashion as shown below for a 24-port switch.
Switch(config)#interface range fastethernet0/1-24
Switch(config-if)#switchport port-security
Switch(config-if)#switchport port-security mac-address sticky
Switch(config-if)#switchport port-security maximum 1

The switchport port-security mac-address command is incorrect since this command requires an additional argument to be valid (either a statically configured MAC address or the sticky option).
The switchport port-security command activates port security on the switch port, but does not configure sticky MAC address learning.
The switchport port-security sticky mac-address and switchport mac-address sticky options are incorrect because these are not valid Cisco IOS commands.
Objective:
Infrastructure Security
Sub-Objective:
Configure, verify, and troubleshoot port security
Cisco > Catalyst 6500 Release 12.2SXH and Later Software Configuration Guide > Configuring Port Security > Enabling Port Security with Sticky MAC Addresses on a Port
Cisco > Cisco IOS Security Command Reference > show vtemplate through switchport port-security violation > switchport port-security mac-address

The following are characteristics of Open Shortest Path First (OSPF) routing protocol:
• The default administrative distance is 110.
• It uses 224.0.0.6 as the multicast address for ALLDRouters.
• It uses the Dijkstra algorithm to calculate the Shortest Path First (SPF) tree.
• It uses Internet Protocol (IP) protocol 89.
• OSPF supports Non-Broadcast Multi-Access (NBMA) networks such as Frame Relay, X.25, and Asynchronous Transfer Mode (ATM). The default hello interval for NBMA networks is 30 seconds.
• OSPF supports point-to-point and point-to-multipoint connections.
• It also supports authentication.
• OSPF uses 224.0.0.5 as the multicast address for ALLSPFRouters.
• It uses link-state updates and SPF calculations that provides fast convergence.
• OSPF is recommended for large networks due to good scalability.
• It uses cost as the default metric.
• There is no maximum hop count as with distance vector routing protocols. The number of hops to a network can be unlimited.
The option stating that AD of OSPF is 90 is incorrect because 90 is the default administrative distance for an internal Enhanced Interior Gateway Routing Protocol (EIGRP) route.
The option stating that OSPF uses the Diffusing Update algorithm (DUAL) algorithm to calculate the SPF tree is incorrect. The DUAL algorithm is used by EIGRP to calculate the SPF tree.
Keep the following in mind when comparing OSPF and EIGRP:
• EIGRP is vendor specific; OSPF is not
• EIGRP has an AD of 90; OSPF has an AD of 110
• OSPF elects a DR on each multi-access network; EIGRP does not
• OSPF uses cost as its metric, and EIGRP uses bandwidth as its metric
The option stating that OSPF uses 224.0.0.5 as multicast address for ALLDRouters is incorrect because OSPF uses 224.0.0.6 as multicast address for ALLDRouters, and 224.0.0.5 as multicast address for ALLSPFRouters.
Objective:
Routing Fundamentals
Sub-Objective:
Configure, verify, and troubleshoot single area and multi-area OSPFv2 for IPv4 (excluding authentication, filtering, manual summarization, redistribution, stub, virtual-link, and LSAs)
Cisco > Support > IP > IP Routing > Technology Information > Technology White Paper > OSPF Design Guide > Document ID: 7039
Cisco > Support > IP > IP Multicast > Technology Information > Technology Briefs > Internet Protocol IP Multicast Technology