Answers to Chapter 10 Do I Know This Already Quiz

1 Name the three types of traffic available in today's multimedia environment Unicast traffic, broadcast traffic, and multicast traffic. 2 What Layer 4protocol is used to carry multicast traffic The transport layer protocol UDP is used to carry multicast traffic. UDP is a simpler, more efficient protocol because there is no flow control, reliability, or error recovery added to IP. 3 What Class of IP address is used in a multicast environment IP multicast is Class D. 4 Describe the makeup of the...

Answers to Chapter 13 QA Section

1 What is the main method of out-of-band management for Cisco switches The main method of out-of-band management is the console connection. 2 What is an application that uses SNMP to perform in-band management CiscoWorks 2000. 3 CDP operates at what layer of the OSI model CDP operates at the Data Link Layer. 4 What is the command to verify that RMON is enabled on the switch show snmp 5 Using a troubleshooting model, what step is generally taken after ascertaining all the facts 6 What is the...

Answers to Chapter 2 QA Section

1 Where is the most appropriate place to connect a block of enterprise servers Why A block of enterprise servers should be connected into the core, just as switch blocks are. This maximizes connectivity from the servers to all other devices in the network. In effect, all users will see the same number of switch hops to access a server. Connecting into the core also provides maximum scalability as more server blocks can be added in the future. 2 Describe the differences between Layer 2, Layer 3,...

Answers to Chapter 3 Do I Know This Already Quiz

1 What are the different Ethernet technologies and their associated IEEE standards Ethernet (10 Mbps, IEEE 802.3), Fast Ethernet (100 Mbps, IEEE 802.3u), and Gigabit Ethernet (1000 Mbps, IEEE 802.3z) 2 What benefits result with switched Ethernet over shared Ethernet Switched Ethernet ports receive dedicated bandwidth, have a reduced collision domain, and have increased performance due to segmentation or fewer users per port. 3 At what layer are traditional 10 Mbps Ethernet, Fast Ethernet, and...

Answers to Chapter 3 QA Section

1 What are the different Ethernet technologies and their associated IEEE standards Ethernet (10 Mbps, IEEE 802.3), Fast Ethernet (100 Mbps, IEEE 802.3u), and Gigabit Ethernet (1000 Mbps, IEEE 802.3z) 2 What benefits result with switched Ethernet over shared Ethernet Switched Ethernet ports receive dedicated bandwidth, have a reduced collision domain, and have an increased performance due to segmentation or fewer users per port. 3 When a 10 100 Ethernet link is autonegotiating, which will be...

Answers to Chapter 4 Do I Know This Already Quiz

1 What is a VLAN When is it used A VLAN is a group of devices on the same broadcast domain, as a logical subnet or segment. VLANs can span switch ports, switches within a switch block, or closets and buildings. VLANs are used to group users and devices into common workgroups across geographical areas. VLANs help provide segmentation, security, and problem isolation. 2 What are two types of VLANs, in terms of spanning areas of the campus network End-to-end (spans entire campus network) and local...

Answers to Chapter 4 QA Section

1 What is a VLAN When is it used A VLAN is a group of devices on the same broadcast domain, as a logical subnet or segment. VLANs can span switch ports, switches within a switch block, or closets and buildings. VLANs are used to group users and devices into common workgroups across geographical areas. VLANs help provide segmentation, security, and problem isolation. 2 When a VLAN is configured on a Catalyst switch port, in how much of the campus network will the VLAN number be unique and...

Answers to Chapter 5 Do I Know This Already Quiz

1 What is EtherChannel What types of switch links can it be used with EtherChannel is a method for aggregating multiple physical Ethernet ports into a single logical link. EtherChannel can be used with full-duplex Fast Ethernet or Gigabit Ethernet links. 2 How is traffic distributed over an EtherChannel Traffic is distributed according to addresses contained in frames passing through the switch not according to port loads or equal distribution across the individual ports in a bundle. Switches...

Answers to Chapter 6 Do I Know This Already Quiz

1 What is the basic unit of ATM data What is its basic format (header, payload, and so forth) The basic ATM data unit is the cell. An ATM cell consists of a 5-byte header and a 48-byte payload. 2 What is an ATM edge device What Cisco devices can be used An ATM edge device interfaces native ATM to other media. For example, Cisco Catalyst switches (5000 and 6000) can be used to bridge between LAN ports and an ATM LANE module. Also, Cisco routers (4500 4700, 7500, for example) can bridge between...

Answers to Chapter 9 Do I Know This Already Quiz

1 What is the name of the protocol that allows a set of routers that are working together to form one virtual-router Hot Standby Router Protocol or HSRP. 2 What is the minimum number of routers needed to perform HSRP The minimum number of routers needed is at least two. One functions as an active router and one as a standby. 3 In a properly functioning virtual router, what happens when the active router fails In a properly functioning HSRP environment, packets will still be routed in the event...

Answers to Chapter 9 QA Section

1 What is the name of the protocol that allows a set of routers that are working together to form one virtual router Hot Standby router Protocol or HSRP. 2 What problem makes HSRP necessary The fact that there isn't a dynamic protocol to discover new default gateways for hosts in the event of failure. 3 What is the minimum number of routers needed to perform HSRP The minimum number of routers needed is at least two. One functions as an active router and one as a standby. 4 What is the RFC that...

Backbone Fast Redundant Backbone Paths

In the network backbone, or Core layer, a different method is used to shorten STP convergence. BackboneFast works by having a switch actively determine if alternate paths exist to the root bridge in the event that the switch detects an indirect link failure. Indirect link failures occur when a link not directly connected to a switch fails. A switch detects an indirect link failure when it receives inferior BPDUs from its Designated Bridge on either its root port or a blocked port. (Inferior...

Bridging Loops

Recall that a Layer 2 switch mimics the function of a transparent bridge. A transparent bridge must offer segmentation between two networks, while remaining transparent to all the end devices connected to it. For the purpose of this discussion, consider a two-port Ethernet switch and its similarities to a two-port transparent bridge. A transparent bridge (and the Ethernet switch) must operate as follows The bridge has no initial knowledge of the location of any end device therefore, the bridge...

Broadcast Traffic

In a broadcast design, an application sends only one copy of each packet using a broadcast address. If this technique is used, however, broadcasts either must be stopped at the broadcast domain boundary with a Layer 3 device or transmitted to all devices in the campus network. Broadcasting a packet to all devices can be inefficient if only a small group in the network actually needs to see the packet as demonstrated in Figure 10-3. Broadcast multimedia is dispersed throughout the network just...

Cisco Discovery Protocol CDP

Cisco Discovery Protocol (CDP) is media- and protocol-independent and runs on all Cisco-manufactured equipment including routers, bridges, access and communication servers, and switches. With CDP, network management applications can retrieve the device type and the SNMP-agent address of neighboring devices (see Figure 13-5). Applications are now enabled to send SNMP queries to neighboring devices. Figure 13-5 A Typical Cisco Network Environment with CDP Enabled Figure 13-5 A Typical Cisco...

Configure Routing Processes

Once connectivity has been configured between the switch and a route processor, you must also configure routing. Routes are paths to distant networks known on the local route processor, along with metrics for path costs and the addresses of next-hop route processors. In this fashion, a router hands off packets destined for a remote network to a neighboring router who is closer to the destination. Routers are used by end-user devices when the destination is not attached to the local network...

Configuring a Rendezvous Point

One of the features that you have to configure if you use PIM in sparse mode is a Rendezvous Point (RP). The routers learn that they are RPs automatically. RPs are used by multicast senders in a sparse mode environment to announce their existence. Through the destination, receivers learn about new senders. Multi-RP environments can be configured for any given multicast group. One term used in the description of RPs is leaf routers. Leaf routers are either directly connected to a multicast group...

Configuring IP Multicast

IP multicast and the task configuring it are somewhat advanced topics. Fortunately, the material on the CCNP Switching exam covers only the basics of configuring IP multicast. We will do the same here, but will list as optional a few of the advanced tasks. The two basic tasks in enabling multicast are Enabling IP multicast routing Enabling PIM on an interface Advanced tasks are optional and include the following Configuring a rendezvous point Configuring the Time To Live (TTL) threshold...

Configuring Multilayer Switching

The basic tasks for configuring multilayer switching include the following 2 Assigning a VLAN ID to a route processor interface. 3 Adding the interfaces to the same VLAN Trunking Protocol (VTP) domain as the switch. 4 Enabling MLS on every interface. 5 Configuring the MLS Management interface. Before you can configure MLS for a specific VLAN or interface, you must globally enable the MLSP that operates between the route processor and the switch. To enable MLSP on the route processor, enter the...

Contents at a Glance

Chapter 1 All About the Cisco Certified Network Professional and Design Professional Certification 3 Chapter 2 Campus Network Design Models 15 Chapter 3 Basic Switch and Port Configuration 65 Chapter 4 VLANs and Trunking 97 Chapter 5 Redundant Switch Links 145 Chapter 6 Trunking with ATM LANE 203 Chapter 7 InterVLAN Routing 241 Chapter 8 Multilayer Switching 265 Chapter 9 Overview of Hot Standby Routing Protocol 301 Chapter 11 Configuring Multicast Networks 369 Chapter 12 Controlling Access in...

Debugging Multicast

Many potential commands can be used when debugging multicast. We will go over a couple of the most important here. You can find documentation on other debugging commands at CCO (www.cisco.com). The first command of significance, show ip pim neighbor, displays the PIM neighbor table as demonstrated earlier in Example 11-1. Another relevant command, show ip mroute, shows the entries in the multicast routing table. The general syntax for this command is as follows DallasR1> show ip mroute...

Displaying MLS Cache Entries

To display the MLS cache entries, enter the following command in privilege EXEC mode This command might be used as a troubleshooting tool or just to check the status of a particular flow that you're interested in. This command can be further defined to show MLS cache entries for the parameters defined in Table 8-2. To remove entries from the MLS cache, enter the clear mls entry command in privilege EXEC mode. Table 8-3 lists how to remove MLS cache entries based on given criteria. Table 8-2...

Distribution Layer Switches

Switches used in the distribution layer should offer these features Aggregation of access layer devices High Layer 3 throughput InterVLAN routing Robust Layer 3 functionality In the distribution layer, uplinks from all access layer devices are aggregated, or come together. Therefore, the distribution layer switches must be capable of processing the total volume of traffic from all the connected devices. These switches should have a port density of high-speed links to support the collection of...

Distribution Trees

For efficient transmission of multicast traffic, designated routers construct a tree that connects all members of an IP multicast group. A distribution tree specifies a unique forwarding path between the subnet of the source and each subnet containing members of the multicast group. A distribution tree has just enough connectivity so that there is only one loop-free path between every pair of routers. Because each router knows which of its lines belong to the tree, the router can copy an...

Do I Know This Already Quiz

The purpose of the Do I Know This Already quiz is to help you decide which parts of this chapter to use. If you already intend to read the entire chapter, you do not necessarily need to answer these questions now. The quiz helps you make good choices of how to spend your limited study time. The quiz is sectioned into five smaller quizlets, which correspond to the five major headings in the Foundation Topics section of the chapter. Although your answer may differ somewhat from the answers given,...

Electing a Root Bridge

For all switches in a network to agree on a loop-free topology, a common frame of reference must exist to use as a guide. This reference point is called the Root Bridge. (The term bridge continues to be used even in a switched environment because STP was developed for use in bridges. Therefore, when you see bridge, think switch.) The Root Bridge is chosen by an election process among all connected switches. Each switch has a unique Bridge ID that it uses to identify itself to other switches....

Electing Designated Ports

By now, you should begin to see the process unfolding a starting or reference point has been identified, and each switch connects itself toward the reference point with the closest single link. A tree structure is beginning to emerge, but links have only been identified at this point. All links are still connected and could be active, leaving bridging loops. To remove the possibility of bridging loops, STP makes a final computation to identify one Designated Port on each network segment....

Electing Root Ports

Now that a reference point has been nominated and elected for the entire switched network, each non-root switch must figure out where it is in relation to the Root Bridge. This action can be performed by selecting only one Root Port on each non-root switch. STP uses the concept of cost to determine many things. Selecting a Root Port involves evaluating the Root Path Cost. This value is the cumulative cost of all the links leading to the Root Bridge. A particular switch link has a cost...

Enabling and Verifying Port Security Using the set CLI on set Command Based Switches

Use the following commands to enable and verify port security on a set command-based switch Switch (enable) set port security mod_num port_num enable mac address Switch (enable) show port mod_num port_num For example, consider the setup in Figure 12-5. Figure 12-5 Enabling and Verifying Port Security Example 12-8 demonstrates how to enable and then verify port security for the set command-based switch in Figure 12-5. Example 12-8 Enabling Verifying Port Security on a set Command-Based Switch...

Enabling PIM on an Interface

When you enable multicast routing on a route processor or router, it is processed on an individual interface basis. Enabling each individual interface used with a specific multicast routing protocol is necessary. The command to enable PIM on an interface is DallasR1> (config-if) ip pim dense-mode sparse-mode sparse-dense-mode The options for this command are defined as follows. dense-mode Enables dense mode of operation. Dense mode is used when all routers in the network will need to...

Enabling VTP Pruning on a CLIBased Switch

VTP pruning is enabled using the set vtp pruning enable command. If this command is used on a VTP server, pruning is enabled for the entire management domain. By default, VTP pruning is disabled. When pruning is enabled with this command, all VLANs become eligible for pruning on all trunk links, if needed. The default list of pruning eligibility can be modified. Like VLAN trunking, you can first clear VLANs from the eligibility list using the clear vtp pruneeligible vlan-range command. Then,...

Extent of VLANs

To implement VLANs, you must give some consideration to the number of VLANs you'll need and how best to place them. As usual, the number of VLANs will be dependent on traffic patterns, application types, segmenting common workgroups, and network management requirements. However, an important factor to consider is the relationship between VLANs and the IP addressing schemes used. Cisco recommends a one-to-one correspondence between VLANs and IP subnets. This recommendation means that if a Class...

Foundation Summary

The Foundation Summary is a collection of tables and figures that provides a convenient review of many key concepts in this chapter. For those of you already comfortable with the topics in this chapter, this summary could help you recall a few details. For those of you who just read this chapter, this review should help solidify some key facts. For any of you doing your final prep before the exam, the following tables and figures will hopefully be a convenient way to review the day before the...

Foundation Topics ATM Review

This section presents a brief review of ATM concepts and operation. Although it is not necessary to know the intimate details of ATM, how to configure an ATM switch, or how the underlying ATM protocols work, you should understand ATM well enough to effectively design and configure LANE. ATM is designed to provide multiple service types (voice, video, and data) over single pipelines very efficiently. All traffic is transported as small fixed-size cells. As well, traffic is not moved based on...

Hierarchical Network Design

The campus network can be structured so that each of the three types of traffic flows or services outlined in Table 2-3 can be best supported. Cisco has devised a hierarchical approach to network design that enables network designers to logically create a network by defining and using layers of devices. The resulting network is efficient, intelligent, scalable, and easily managed. The hierarchical model breaks a campus network down into three distinct layers, as illustrated in Figure 2-6....

How to Best Use This Chapter

By taking the following steps, you can make better use of your study time Keep your notes and the answers for all your work with this book in one place for easy reference. Take the Do I Know This Already quiz and write down facts and concepts, even if you never look at the information again. Use the diagram in Figure 5-1 to guide you to the next step.

How to Use This Book to Pass the Exam

One way to use this book is to start at the beginning and read it cover to cover. Although that would help you prepare, most people would not take that much time, particularly if you already knew a lot about some of the topics in the book. The rest of you might want to consider a different strategy on how to best use this book, depending on what training you have had. This book is designed to help you get the most out of the time you take to study. At the beginning of each chapter, you are...

InterVLAN Routing Configuration

This section presents a more detailed look at configuring interVLAN routing using both external and integrated Cisco route processors. Routing, in itself, is a complex and extensive topic. Only the basic routing protocol configuration is presented here, to provide simple but functional routing between VLANs. If you need further information on the various routing protocols, refer to the Interconnecting Cisco Network Devices (ICND) and Building Scalable Cisco Networks (BSCN) courses or course...

Issues with Traditional Methods

This section deals with various traditional methods that have been used, but for one reason or another are ineffective in some failure modes. These methods include default gateways, proxy ARP, RIP, and IRDP. In Figure 9-2, Router A is responsible for routing packets for Subnet A, and Router B is responsible for handling packets on Subnet B. If Router A goes down or otherwise becomes unavailable to the PC, the routing protocols used between the rest of the routers will converge at some point and...

LAN Segmentation Model

Referred to as network segmentation, localizing the traffic and effectively reducing the number of stations on a segment is necessary to prevent collisions and broadcasts from reducing a network segment's performance. By reducing the number of stations, the probability of a collision decreases because fewer stations can be transmitting at a given time. For broadcast containment, the idea is to provide a barrier at the edge of a LAN segment so that broadcasts cannot pass or be forwarded on...

LANE Configuration

This section discusses the procedures for configuring the various LANE components on Cisco Catalyst switches. The order that the components are configured is important because each component is dependent upon another. On Cisco ATM devices, ELANs are configured on ATM subinterfaces. This configuration makes it possible to support many ELANs over a single ATM link. As well, the LANE components necessary for a specific ELAN must be configured on the respective subinterface for that ELAN (ATM 0.1,...

Managing Multicast Traffic

In the world of multicasting, the concept of sending a multicast within a single broadcast domain is a somewhat trivial process. However, when we extend this into multiple segments within a campus environment over multiple switches and routers, we complicate matters significantly. The sending process specifies a destination address defined as a multicast address. The device driver in the sending server converts this address to the corresponding Ethernet address and sends the packet out on the...

MLS Caching

MLS caching is a process that occurs based on individual flows. In this section, we will walk through the process, step by step, in order to gain an intimate knowledge of just what occurs. The Switching Engine (SE) is involved in the process to maintain the cache for MLS flows. Packets in a flow are compared to the cache. Cache entries are based on one-way flows. In other words, a flow from Host A to Host B would be one flow and a flow in the reverse direction would be another flow. This action...

Multicast Address Structure

IP multicasting is the transmission of an IP data frame to a multicast group, identified by a single IP address. Because the multicast group is identified by a single IP address rule, the IP multicast datagram contains a specific combination of the destination MAC address and a destination IP address. The range of IP addresses is divided into classes based on the high order bits of a 32-bit IP address. IP multicast uses Class D addresses. A Class D address consists of 1110 as the higher order...

Multicast Traffic

The most efficient solution for transmitting multimedia is one in which a multimedia server sends one copy of each packet, addressing each packet to a special multicast address. Unlike the unicast environment, a multicast server sends out a single data stream to multiple clients. Unlike the broadcast environment, the client device decides whether to listen to the multicast address. Multicasting saves bandwidth and controls network traffic by forcing the network to replicate packets only when...

Multilayer Switching

Switching technologies have matured over the years and now are a standard part of the campus network. Switching has solved a couple of problems, namely a lack of bandwidth and the inability to have disparate physical groups logically connected. Recently we've taken switching to a higher level, incorporating a routing function within the switch itself. Add some new software that allows true Layer 3 switching, and you have a recipe for success in the campus network. The performance levels are...

Output Lists

Figure 8-5 illustrates an output access list applied to the interface. In this case, the MLS-SE learns of this change through the MLSP process and then enforces security for the flow. Enforcement of the access list would purge any entries for flows on that interface from the MLS cache. Any new flows would then be created based on the restrictions imposed by the access list. The next packet in the flow becomes a candidate packet and the process of establishing a MLS cache entry is initiated. New...

Overview of Hot Standby Router Protocol

Hot Standby Router Protocol (HSRP) was conceived as a method of providing a level of fault tolerance in the network. HSRP is a Cisco proprietary protocol that is outlined in RFC 2281 (www.isi.edu in-notes rfc2281.txt). The HSRP protocol protects against a failure of the first-hop router. HSRP picks up where the default router left off. You can have a routing protocol capable of discovering dynamic routes, but when it comes to the default route on hosts, there isn't a means to change this in the...

Overview of Multilayer Switching

Catalyst switches are the basis for Layer 3 switching in the Cisco environment. Multilayer Switching (MLS) performs IP data (also IPX and IP multicast) packet flows at a much higher level of performance than traditional routing. This preserves the CPU of an upstream router without compromising functionality. Figure 8-2 shows that the first packet through enters and exits the router illustrated. Subsequent packets would be switched. Figure 8-2 Multilayer Switching Flow First Packet Through...

Passwords and User Access

Normally, a network device should be configured to secure it from unauthorized access. Catalyst switches offer a simple form of security by setting passwords to restrict who can log in to the user interface. Two levels of user access are available regular login, or EXEC mode, and enable login, or privileged mode. EXEC mode is the first level of access, which gives access to the basic user interface through any line or the console port. The privileged mode requires a second password and gives...

Physical Layer Troubleshooting

The most common network problems can be traced to cable problems. The following questions will help determine whether there is a UTP cable problem. Are the cables the correct type for this installation Category 3 cabling can only support 10BaseT. Was a Category 3 cable installed instead of a category 5 For Category 5 cabling, was the cable installed correctly Severe bends in a Category 5 cable can cause a 10 100-Mbps interface to run at 10 Mbps. Some devices do not handle auto negotiation...

Routing over Trunk Links

A more robust and cost effective approach uses trunk links between the switches and routers, instead of multiple physical links. Because trunk links transport multiple VLANs over a single link, only one link to an external router is required. A router connected to a switch by a single trunk link is usually referred to as a router on a stick, or a one-armed router. However, a router can also connect to several switches using trunk links. This connection provides end-to-end Layer 3 connectivity...

Scenario 111 Answers

1 To configure IP multicast on the router, enter the following command at the global configuration prompt 2 To configure PIM in sparse mode, enter the following command at the interface prompt Router (config-if) ip pim sparse-mode 3 To display PIM information about interface VLAN10, enter the following command at the prompt 4 To display the PIM neighbor tables, enter the following command at the prompt 5 To configure an RP, enter the following command while in global configuration mode...

Scenario 122 Answers

1 The correct answer is as follows Switchl(enable)set banner motd Unauthorized access will be prosecuted 2 The correct configuration is as follows interface VLAN100 access-group 101 out access list 101 permit tcp any any eq smtp 3 The correct configuration is as follows router eigrp 225 network 172.16.0.0 distribute-list 5 out VLAN200 access-list 5 permit 172.16.100.0 0.0.0.255 4 The configuration that accomplishes the goal for this exercise is as follows privilege configure level 3 username...

Scenario 23 Answers Large Enterprise Campus Network Design

1 This network could be improved by moving toward a hierarchical campus design. A Layer 2 backbone is being used with two switches, though they are not redundant. The distribution layer uses traditional routers, causing a potential bottleneck for all traffic passing into the core. All other enterprise resources connect into the distribution layer routers, probably because the routers inherently support WAN connections and Layer 3 routing. 2 See Figure 2-15 for a new network design drawing....

Scenario 51 Answers Spanning Tree Protocol Operation

1 The Spanning-Tree topology should look like the diagram in Figure 5-11. Catalyst A is the Root Bridge and only the 1000-Mbps link is Forwarding. The Root Ports (RP) and Designated Ports (DP) are labeled on the diagram. 2 Because the 100-Mbps link is in the Blocking state on Catalyst B, no major change in the topology will occur. Effectively, this link was already disconnected. However, after the physical link status goes down, both Catalyst A and Catalyst B will sense the change and begin...

Scenario 61 Answers

1 The LECS could be placed on either Catalyst A, B, or C. The LES BUS for ELAN 101 could be placed on either A or B, and the LES BUS for ELAN 102 could be placed on either A, B, or C. A LEC for ELAN 101 must be placed on Catalyst A and B. A LEC for ELAN 102 must be placed on all three Catalysts. 2 The commands needed are as follows interface atm 0.1 multipoint lane client Ethernet 101 ELAN101 3 A host on Catalyst A VLAN 101 can indeed communicate with a host on Catalyst B VLAN 101. Because VLAN...

Scenario 82 Answers

1 Example 8-16 shows the correct configuration for Scenario 8-2. Example 8-16 Scenario 8-2 Configuration Switch (enable)show config (Text Deleted) mls 2 There are three VLANs and they are VLAN 1, VLAN 4, and VLAN5. 4 Because there is an included router, this is the sign that the RP is an external router, rather than an RSM. This chapter covers the following topics that you will need to master for the CCNP Switching Exam HSRP Overview This section outlines an overview of Hot Standby Router...

Scenario 91 Answers

1 To activate HSRP on an interface, you must use the standby command as follows ip address 192.168.1.1 255.255.255.0 2 Configuring Router B to be the active router involves the use of the priority command as shown in the following sample configuration interface Vlan10 ip address 192.168.1.3 255.255.255.0 no ip redirects standby 99 ip 192.168.1.2 standby 99 priority 150 3 Building on the configuration as we go forward, we add the preempt command to allow Router B to recover as the active router...

Scenario Answers

1 The link is still an access link, with no trunking established. The two switches would have negotiated trunking, but the switches are configured for different VTP management domains. Neighboring switches must be in the same domain for trunking to be negotiated. 2 Catalyst A can ping Catalyst B. The SCO ports on both switches are configured for the same VLAN. Because trunking has not been established between Catalyst A and Catalyst B (due to domain name conflicts), the link is still an access...

Shared Network Model

Campus networks have traditionally been constructed of a single LAN for all users to connect to and use. All devices on the LAN were forced to share the available bandwidth. LAN media such as Ethernet and Token Ring both have distance limitations, as well as limitations on the number of devices that could be connected to a single LAN. Network availability and performance both declined as the number of connected devices increased. For example, an Ethernet LAN required all devices to share the...

Sizing a Switch Block

Containing access and distribution layer devices, the switch block is simple in concept. You should consider several factors, however, to determine an appropriate size for the switch block. The range of switch devices available makes the size of the switch block very flexible. At the access layer, switch selection is usually based on port density or the number of connected users. The distribution layer must be sized according to the number of access layer switches that are collapsed or brought...

Spanning Tree Communication Bridge Protocol Data Units

STP operates as switches communicate with one another. Data messages are exchanged in the form of Bridge Protocol Data Units (BPDUs). A switch sends a BPDU frame out a port, using the unique MAC address of the port itself as a source address. The switch is unaware of the other switches around it. Therefore, the BPDU frame has a destination address of the well-known STP multicast address 01-80-c2-00-00-00 to reach all listening switches. There are two types of BPDU the Configuration BPDU, used...

TDRs and OTDRs

At the top end of the cable-testing spectrum are time domain reflectometers (TDRs). These devices can quickly locate open and short circuits, crimps, kinks, sharp bends, impedance mismatches, and other defects in metallic cables. A TDR works by bouncing a signal off the end of the cable. Opens, shorts, and other problems reflect the signal back at different amplitudes depending on the problem. A TDR measures how much time it takes for the signal to reflect and calculates the distance to a fault...

Telnet Client Access

Remote, in-band SNMP management is possible through any LAN or ATM interface assigned to the same VLAN as the Supervisor module's NMP IP address. In-band connections can be used to establish Telnet sessions to the Cisco switch CLI or SNMP management sessions on an SNMP-based management platform, such as CiscoWorks 2000. Cisco switches provide outgoing Telnet functionality from the CLI this feature allows a network manager to use Telnet from the CLI of the switch to other devices on the network....

The set snmp Command Options

The syntax for the set snmp community command, used to configure SNMP community strings, is as follows set snmp community read-only read-write read-write-all community_string The keywords for the set snmp community command are as follows read-only Keyword to assign read-only access to the specified SNMP community. read-write Keyword to assign read-write access to the specified SNMP community. read-write-all Keyword to assign read-write access to the specified SNMP community. The read-write-all...

Token Ring Bridging

To form larger networks, Token Rings are interconnected with bridges. Although a transparent bridge (or one that forwards frames based solely on MAC addresses) can be used, IBM designed and introduced Token Ring differently. Source-route bridges are used to forward frames between rings, based on a predetermined path. The source station includes the exact ring-and-bridge path within the frame so that specific bridges will forward the frame to the appropriate rings. Rings must be uniquely...

TrCRF Redundancy

Catalyst switches also offer a form of redundancy for Token Ring switching. When two switches are connected by a common TrBRF and ISL trunking is enabled, connectivity between the TrCRFs in the switches could be disrupted if the ISL trunk link fails. A backup TrCRF can be used to provide a backup path in this case. For each TrBRF, a single backup TrCRF can be defined with a single port from each connected switch. Only one of the TrCRF ports will be active at all times, while the other ports...

Troubleshooting with show Commands

Enter the show system command to display the power supply, fan, temperature alarm, system, and modem status the number of days, hours, minutes, and seconds since the last system restart the baud rate the MAC address range and the system name, location, and contact. Example 13-13 demonstrates typical information displayed by entering the show system command. Example 13-13 show system Command Output Console> show system PS-Status Fan-Status Temp-Alarm Sys-Status Uptime d,h m s disabled 9600...

Understanding HSRP Interface Tracking

In some situations, the status of an interface directly affects which router needs to become the active router. This is particularly true when each of the routers in an HSRP group has a different path to resources within the campus network. In the campus LAN example in Figure 9-6, Router A and Router B reside in a branch office. These two routers each support a serial link to headquarters. Router A has the higher priority and is the active forwarding router for standby group 47. Router B is the...

VLAN Membership

When a VLAN is provided at an access layer switch, an end user must have some means to gain membership to it. Two membership methods exist on Cisco Catalyst switches static VLANs and dynamic VLANs. Static VLANs offer port-based membership, where switch ports are assigned to specific VLANs. End user devices become members in a VLAN based on which physical switch port they are connected to. No handshaking or unique VLAN membership protocol is needed for the end devices they automatically assume...

VLAN Trunk Configuration on a CLIBased Switch

To create a VLAN trunk link, use the set trunk CLI-based command. This command sets the trunking mode and any mode negotiation. The set trunk command also identifies the VLANs that will be transported over the trunk link. Trunk configuration uses the following command syntax Switch(enable) set trunk module port on off desirable auto nonegotiate vlan-range isl dot1q dot10 lane negotiate Here, the trunk link is identified by its physical location as the switch module number and port number. The...

VTP and Token Ring VLANs

Using VTP in a Token Ring network domain will simplify VLAN administration, just as it does for Ethernet. TrCRF information will be propagated to all switches in a management domain. As well, VTP pruning can also be performed on Token Ring VLANs. Both the default TrBRF (VLAN 1005) and the default TrCRF (VLAN 1003) are always pruning ineligible. VTP pruning is configured on a per-TrBRF basis. When a TrBRF is made pruning-eligible, all TrCRFs connected to it are also made pruning-eligible.

Overview of Cisco Certifications

Cisco's main motivation behind the current certification program is to provide a means of measuring the skills of people working for Cisco Resellers and Certified Partners. Cisco fulfills only a small portion of its orders via direct sale from Cisco most times, a Cisco reseller is involved. Cisco has not attempted to become the only source for consulting and implementation services for network deployment using Cisco products. In 1996-97 Cisco embarked on a channel program whereby business...

Topics on the Exam

The following list outlines the various topics that you will likely encounter on the exam. The topics represent a detailed list for areas of focus but are not intended as a list of test question topics. Each listed item may have subitems that will be tested on. Table 1-3 lists the exam topics in the order that they are found within this book. Table 1-3 CCNP CCDP Switching Exam Topics Table 1-3 lists the exam topics in the order that they are found within this book. Table 1-3 CCNP CCDP Switching...

Whats on the Switching Exam

As with other Cisco exams, the exact exam content is not publicly known. In fact, Cisco makes fairly general Switching Exam content available to the public at www.cisco.com warp public In addition to the general content listed, this book is structured to cover the content of the Building Cisco Multilayer Switched Networks (BCMSN) course. This content provides full coverage of switching topics that might be encountered in either the Switching Exam or real-world CCNP CCDP workplace.

S

SAID (Security Association Identifier), 104 SAP (Service Advertisement Protocol), 24 SAR (Segmentation and Reassembly), 209 scaling core blocks, 47 Layer 2 switching, 21 link bandwidth, 150-155 scenarios 14-1, 464, 469-470 14-2, 465-466, 471-472 14-3, 467-468, 472-474 scope of delivery, TTL fields, 357 access policies, 398-407 core layer policy, 415 distribution layer policy, 408- 415 passwords, 81 Security Association Identifier (SAID), 104 segmentation, 22-26 Segmentation and Reassembly...

VLAN Frame Identification

Because a trunk link can be used to transport many VLANs, a switch must identify frames with their VLANs as they are sent and received over a trunk link. Frame identification, or tagging, assigns a unique user-defined ID to each frame transported on a trunk link. This ID can be thought of as the VLAN number or VLAN color, as if each VLAN was drawn on a network diagram in a unique color. VLAN frame identification was developed for switched networks. As each frame is transmitted over a trunk...

Configuring the VTP Version

Two versions of VTP are available for use in a management domain. Catalyst switches are capable of running either VTP version 1 or VTP version 2. Within a management domain, the two versions are not interoperable. Therefore, the same VTP version must be configured on each switch in a domain. VTP version 1 is the default protocol on a switch. If a switch is capable of running VTP version 2, however, a switch may coexist with other version 1 switches, as long as its VTP version 2 is not enabled....

Contents

Strategies for Exam Preparation xxiv Chapter 1 All About the Cisco Certified Network Professional and Design Professional Certification 3 Overview of Cisco Certifications 4 Exams Required for Certification 5 Other Cisco Certifications 6 Recommended Training Path for CCNP and CCDP 8 How to Use This Book to Pass the Exam 9 I've Taken BCMSN Now What 11 I've Taken CLSC Now What 11 I've Learned Switching From Experience, But I Will Not Be Taking the BCMSN Course Now What 12 Chapter 2 Campus Network...

Privilege Levels

The two default levels of access are user and privileged. The user level allows the user to perform certain commands but does not give them the ability to modify the configuration or perform a debug. At the other end of the spectrum, the privileged level allows the user to issue all commands, including configuration and debug commands. Cisco IOS provides different levels of privileges for users with the use of the privilege level command. This command allows network administrators to provide a...

Token Ring VLANs

This section discusses VLANs as they are applied to Token Ring networks. Only the Catalyst 5000 and the Catalyst 3900 switches support Token Ring both using CLI-based commands. Recall from the discussion in Chapter 3, Basic Switch and Port Configuration, the basic topology of Token Ring networks. End stations are connected to multistation access units (MSAUs), which interconnect with other MSAUs to form a ring. Multiple rings can be interconnected by bridges for segmentation and frame...

CCIE Professional Development

Kennedy Clark, CCIE Kevin Hamilton, CCIE 1-57870-094-9 AVAILABLE NOW This volume provides an in-depth analysis of Cisco LAN switching technologies, architectures, and deployments, including unique coverage of Catalyst network design essentials. Network designs and configuration examples are incorporated throughout to demonstrate the principles and enable easy translation of the material into practice in production networks. Alvaro Retana, CCIE Don Slice, CCIE and Russ White, CCIE 1-57870-097-3...

All About the Cisco Certified Network Professional and Design Professional Certification

The Cisco Certified Network Professional (CCNP) and Cisco Certified Design Professional (CCDP) certifications are the second level of Cisco certifications and are becoming popular as more incentives become available to both certification holders and their employers. Cisco has designed both the CCNP and CCDP certifications as evidence that an individual has completed a rigorous path of testing in the network arena. The CCNP and CCDP tracks require the candidate to be comfortable in advanced...

Hot Standby Router Protocol

So what problem are we trying to solve We've looked at solutions that try to solve the problem of a network failure, but for various reasons don't necessarily fix the problem. Enter Hot Standby Router Protocol. HSRP addresses the problem caused by first-hop failures generally having static default gateway addresses on hosts. Previously, a failure at the default gateway address would leave the host unable to communicate outside of its own subnet. Now with HSRP, the default gateway is a...

Conclusion

The CCNP Switching Exam Certification Guide is designed to help you attain CCNP certification by successfully preparing you to pass the Switching Exam. This book is the Switching Exam certification book from the only Cisco-authorized publisher. We at Cisco Press believe that this book certainly can help you prepare for and pass the Switching Exam but the real work is up to you We trust that your time will be well spent. This chapter covers the following topics that you will need to master for...

Distributing Traffic in Ether Channel

Traffic in an EtherChannel is statistically load-balanced across the individual links bundled together. However, the load is not necessarily balanced equally across all of the links. Instead, frames are forwarded on a specific link as a function of the addresses present in the frame. Some combination of source and destination addresses (either MAC or IP addresses) is used to form a binary pattern used to select a link number in the bundle. Switches perform an exclusive-OR (XOR) operation on one...

Root Bridge Placement

While STP is wonderfully automatic with its default values and election processes, the resulting tree structure may perform quite differently than expected. The Root Bridge election is based on the idea that one switch is chosen as a common reference point, and all other switches choose ports that are closest to the Root. The Root Bridge election is also based on the idea that the Root Bridge can become a central hub that interconnects other legs of the network. Therefore, the Root Bridge can...

Answers to Chapter 6 QA Section

1 What is the basic unit of ATM data What is its basic format (header, payload, etc.) The basic ATM data unit is the cell. An ATM cell consists of a 5-byte header and a 48-byte payload. 2 What process allows an IP packet to be transported within ATM cells Segmentation and Reassembly (SAR) provided by the ATM Adaptation Layer (AAL). 3 What is an ATM edge device What Cisco devices can be used An ATM edge device interfaces native ATM to another media. For example, Cisco Catalyst switches (5000 and...

Full Duplex Fast Ethernet

As with traditional Ethernet, the natural progression to improve performance is to use full-duplex operation. Fast Ethernet can provide 100 Mbps in each direction on a switched connection, for 200 Mbps total throughput. This throughput is only possible when a workstation or server is directly connected to a switch port, or when two switches directly connect to each other. The Fast Ethernet specification also offers backward compatibility to support traditional 10 Mbps Ethernet. To provide this...

Answers to Chapter 5 QA Section

1 What is EtherChannel What types of switch links can it be used with EtherChannel is a method for aggregating multiple physical Ethernet ports into a single logical link. EtherChannel can be used with full-duplex Fast Ethernet or Gigabit Ethernet links. 2 How does an EtherChannel distribute broadcasts and multicasts Broadcasts and multicasts are sent across only one port of the bundle and are not distributed across the EtherChannel. 3 How is traffic distributed over an EtherChannel Traffic is...

Establishing VLAN Connectivity

Next, the route processor will need to have its interfaces configured to support connectivity to the necessary VLANs. This is accomplished using interfaces and commands that are unique to the route processor hardware. The following sections present this information for each type of link between the route processor and switches. Establishing VLAN Connectivity with Physical Interfaces External routers are connected to switches using traditional LAN media links. For example, Ethernet, Fast...

MLS Management Interface

When a RSM or router is configured to participate in MLS, the device uses the MLSP to send Hello messages, advertise routing changes, and announce the VLANs or MAC addresses of those interfaces on the devices participating in MLS. One interface on the MLS-RP must be identified as the management interface through which MLSP packets are sent and received. The MLSP management interface can be any MLS interface connected to the switch. Only one management interface needs to be specified. If no...

About the Authors

Tim Boyles is the Director of Network Architecture for Link Networks, a national CLEC which specializes in broadband data and communications solutions for small- and medium-sized businesses. Prior to that he worked as a Senior Consultant at Lucent Networkcare, formerly known as INS, where he was responsible for the design and implementation of large switch-based networks as well as multiple service provider projects. Tim has been in the networking business for 16 years with multiple vendor...

Exams Required for Certification

To certify for CCNP or CCDP, successful completion of a group of exams is required. The exams generally match the same topics that are covered in one of the official Cisco courses. Table 1-1 outlines the exams and the courses with which they are most closely matched. Course Most Closely Matching Exam Requirements Interconnecting Cisco Network Devices (ICND) Building Scalable Cisco Networks (BSCN) Building Cisco Multilayer Switched Networks (BCMSN) Building Cisco Remote Access Networks (BCRAN)...

Recommended Training Path for CCNP and CCDP

The recommended training path for the Cisco CCNP 2.0 and CCDP 2.0 professional level certifications is as follows Building Scalable Cisco Networks (BSCN) Covers the advanced routing protocols and the scaling issues involved with a large routed network with multiple protocols. Building Cisco Multilayer Switched Networks (BCMSN) Covers the switch infrastructure and the configuration in a large network environment. Building Cisco Remote Access Networks (BCRAN) Covers the dialup and RAS issues...

Cisco CCNP Switching Exam Certification Guide

Tim Boyles and Dave Hucaby, CCIE 4594 Cisco CCNP Switching Exam Certification Guide Copyright 2001 Cisco Systems, Inc. Cisco Press logo is a trademark of Cisco Systems, Inc. All rights reserved. No part of this book may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without written permission from the publisher, except for the inclusion of brief quotations in a review....