Cisco Discovery 4 Module 6 Picture Descriptions 6.0 Chapter Introduction 6.01 Introduction Slide 1 text An organized, hierarchical IP addressing structure creates a flexible network that can easily scale to meet new demands. Slide 2 text Planning for route summarization ensures that network resources are utilized efficiently. Slide 3 text Assigning logical device names assists in the management and control of the network. Slide 3 text As IPv4 address blocks become scarce, being prepared to implement IPv6 is critical. 6.1.0 - Creating an Appropriate IP Addressing Design 6.1.1 - Using Hierarchical Routing and Addressing Schemes 4 Diagrams Diagram 1, Image Routers: Current stadium addressing scheme Ticket office/ ISP2 192.168.4.1/24 Connects to the Internet via VPN over DSL Vendor network/ISP3 192.168.5.1/24 Connects to the Internet via VPN over DSL ISP1 192.168.2.254 connects to the following switches Stadium management 192.168.2.4 Team 192.168.2.2 Edge router 192.168.2.1 Vendor 192.168.2.5 Luxury suites 192.168.2.3 Stadium management, team services, vendor services and luxury suite devices are also connected to this network range - 192.168.2.0/23 Diagram 2, Image Diagram depicts both a non-hierarchical and hierarchical addressing scheme. The non hierarchical scheme uses various unrelated network addresses (eg 192.168.1.0 and 10.22.5.0) The hierarchical scheme uses a single IP block (172.16.0.0/16 in this case) and breaks it into logical blocks (eg 172.16.4.0/22) Diagram 3, Image No useful information contained, examples of devices that require an IP address Diagram 4, Packet Tracer Exploration 6.1.2 - Classful Subnets and Summarization 2 Diagrams Diagram 1 Animation Animation depicts route summarisation. Topology shown is as follows: Network 172.16.1.0/24 connects to router A, Router A connects to router B on 192.168.7.0/30, router B connects to router C on 192.168.7.4/30 and router C has network 172.16.2.0/24 attached. Routers in this network are running auto-summarization. As a result, Router A and Router C both advertise the summary route 172.16.0.0/16. Router B receives both updates and installs both equal cost routes into the routing table. This causes reachability issues for both the 172.16.1.0 and 172.16.2.0 networks. Router A says ?I know about network 172.16.0.0? router C says I know about network 172.16.0.0? Routing updates are sent to router B from A and C. B says ? I now have 2 equal costs to get to 172.16.0.0. B has a packet for 172.16.2.5 and sends it to both A and C Diagram 2, Packet Tracer Exploration 6.1.3 - Using VLSM when Designing IP Addressing 2 Diagrams Diagram 1, Table Classful: All subnets of the same classes network are equal size and the same subnet mask and prefix length. Classless using VLSM: Subnets can be of various sizes and prefix lengths, as long as there are no overlapping address ranges. Classful Subnet Parent Network = 172.16.0.0/16 172.16.0.0/22 172.16.4.0/22 172.16.8.0/22 172.16.12.0/22 Classful Subnet Parent Network = 172.17.0.0/16 172.17.0.0/24 172.17.1.0/24 172.17.2.0/24 172.17.3.0/24 Classless subnetting using VLSM Parent Network = 172.17.0.0/16 172.16.0.0/16 172.16.0.0/22 172.16.4.0/24 172.16.5.0/24 172.16.6.0/24 172.16.7.0/24 172.16.8.0/22 172.16.12.0/22 Classless subnetting using VLSM Parent Network = 172.17.0.0/16 172.17.0.0/24 172.17.1.0/24 172.17.2.0/24 172.17.3.0/27 172.17.3.32/27 172.17.3.64/27 172.17.3.96/27 172.17.3.128/27 Diagram 2, Packet Tracer Exploration 6.1.4 ? Using CIDR Routing and Summarization 3 Diagrams Diagram 1, Image The picture depicts the use of Route Summarization in a Network. There are two examples, one which shows individual Class B addresses with a default /16 subnet mask, and one which shows a Summarized supernet mask using the same Class B addresses but with a /14 subnet mask to summarize the addresses. Diagram 2, Table R1 Routing Table Route ? 172.18.0.0/16 Source ? Connected Route ? 172.19.0.0/16 Source ? Connected Route ? 172.17.0.0/16 Source ? R2 Route ? 172.16.0.0/16 Source ? R2 Route ? 192.168.1.0/24 Source ? Connected R2 Routing Table Route ? 172.18.0.0/16 Source ? R1 Route ? 172.19.0.0/16 Source ? R1 Route ? 172.17.0.0/16 Source ? Connected Route ? 172.16.0.0/16 Source ? Connected Route ? 192.168.1.0/24 Source ? Connected Route ? 10.1.0.0/16 Source ? Connected R3 Routing Table Route ? 172.16.0.0/14 Source ? R2 Route ? 192.168.1.0/24 Source ? Connected Route ? 10.1.0.0/16 Source - Connected Diagram 3, Hands On Lab Module 6.2 ? Creating the IP address and Naming Scheme 6.2.1 ? Designing the Logical LAN IP Address Scheme 4 Diagrams Diagram 1, Table The picture shows a technician working on an IP addressing scheme for the stadium, there is a caption, which says ?I need to consider the entire campus and all of the remote sites before I begin assigning any addresses.? There is a set of steps as follows: 1. The stadium/Company is expecting significant growth, especially in the wireless area. 2. The five areas I need to group into contiguous blocks that can be summarized include the Stadium Company devices, Team devices, Luxury Suites devices, Data Center Devices, and the four remote sites 3. All of the end user PCs will use DHCP for addressing. I need to statically address the infrastructure devices, including the two core switches, six distribution switches and all of the access switches. I will also need static addresses for the servers and the wireless LAN controllers. 4. I will put my campus DHCP server in the Data Center. I will use the Cisco ISRs at the remote sites for DHCP. I think I can use the DHCP on the wireless controller to assign addresses to the wireless end devices. I will have to figure out what ranges to assign to each DHCP server. Diagram 2, Table The picture depicts a map of the Stadium, and outlines all of the various rooms that will require network equipment. Diagram 3, Image The picture depicts the Stadium Networks Topology. The picture shows that all of the Servers that are accessible to the Internet have had a Static IP address assigned. There is a table at the top of the diagram, which indicates the static NAT redirects for the Servers. Diagram 4, Hands On Lab 6.2.2 ? Determining the Addressing Blocks 2 Diagrams Diagram 1, Image The picture depicts the equipment, which is attached to Wiring closet A The equipment is located in the Team Office A area, and includes 40 computer, 60 IP Phones, 3 Switches, 1 AP, 1 Camera. The picture also show s the Network Requirements Chart, which indicates The Number of Networks, Number of Hosts, and room for growth for each of the four subnets (Data, Voice, Management, Video Surveillance). Diagram 2, Hands On Lab 6.2.3 ? Designing the Routing Strategy 4 Diagrams Diagram 1, Image The picture depicts some of the factors EIGRP incorporates. Routing Protocol EIGRP Classless Routing Small routing updates Updates only when necessary Fast convergence Easy to implement Diagram 2, Image The picture depicts the use of Load Balancing with EIGRP. The network is as follows: Network Four Routers (B, C, D, E) B is connected to E with a metric of 20 E is connected to D with a metric of 20 E is connected to C with a metric of 10 There is a cloud (Network M) B is connected to cloud with a metric of 10 C is connected to cloud with a metric of 10 D is connected to cloud with a metric of 25 Network ? M Neighbor ? B Metric ? 30 Network Neighbor ? C Metric ? 20 Network Neighbor ? D Metric 45 Router E uses the route through Router C to get to the Network M, because it has the lowest reported metric of 20 (10 + 10). To determine which other routes can be used for load balancing traffic to Network M, the EIGRP process on Router E takes the best metric multiplied by the configured variance value. In this case, the best metric is the route through Router C, which has a reported metric of 20. Any route with a metric less than 40 (20 x 2) is installed in the routing table to be used for load balancing. Traffic to Network M, because the metric of 30 is less than 40. EIGRP does not install the route that uses Router D because its metric of 45 is greater than the acceptable value of 40. Diagram 3, Animation There are two scenarios in this Animation Network Two Routers (A, B, C) RouterA is connected to RouterC RouterB is connected to RouterC RouterA has one Host (HostA: 192.168.10.10/24) RouterB has one Host (HostB: 192.168.30.10/24) Attack The picture depicts a Routing loop due to an attack on a network, There is a hacker who manipulates RouterA?s Routing table to redirect packets destined for HostA through RouterB, when the packet reaches RouterB its table states that information destined for HostA should be sent through RouterA, and passes the information back to RouterA. Operation The picture depicts data encryption. HostB sends HostA a packet, the picture identifies how when the packet reaches each Router on the path from HostB to HostA, it is checked using a Key and passed onto the next Router. Diagram 4, Packet Tracer Lab 6.2.4 ? Plan for Summarization and Route Distribution 3 Diagrams Diagram 1, Image The picture depicts an example of Both Classful and Classless Route summarization. Two Switches (S1, S2) Two Multilayer Switches (S3, S4) All four switches are interconnected. Classless Summarization The picture identifies a two summarized routes of 172.16.32.0/121, 172.16.4.0/22 for the following Routes: S1 VLAN1-172.16.34.0/24 VLAN2-172.16.35.0/24 VLAN3-172.16.36.0/24 VLAN4-172.16.37.0/24 S2 VLAN5-172.16.4.0/24 VLAN6-172.16.5.0/24 VLAN7-172.16.6.0/24 VLAN8-172.16.7.0/24 Classlful The picture identifies a single summarized route of 172.16.0.0/16 for the following Routes: S1 VLAN1-172.16.34.0/24 VLAN2-172.16.35.0/24 VLAN3-172.16.36.0/24 VLAN4-172.16.37.0/24 S2 VLAN5-172.16.4.0/24 VLAN6-172.16.5.0/24 VLAN7-172.16.6.0/24 VLAN8-172.16.7.0/24 Diagram 2, Table The picture depicts three steps, which can be used for determining a Route Summary. Step 1: Convert the networks to summarize to binary. Route ? 172.16.1.0 Binary ? 10101100.00010000.00000001.00000000 Route ? 172.16.2.0 Binary ? 10101100.00010000.00000010.00000000 Route ? 172.16.3.0 Binary ? 10101100.00010000.00000011.00000000 Step 2: To find the subnet mask for summarization. Start with the left-most bit. Count the umber of matching bits. Route ? 172.16.1.0 Binary ? 10101100.00010000.00000001.00000000 Route ? 172.16.2.0 Binary ? 10101100.00010000.00000010.00000000 Route ? 172.16.3.0 Binary ? 10101100.00010000.00000011.00000000 The Route boundary has been determined, As the first 22nd bit is the same on all routes and the 23rd bit differs, the boundary is placed between the 22nd and 23rd bit. Step 3: Determine the network address for the summary route. Route ? 172.16.0.0 Binary ? 10101100.00010000.00000000.00000000 Subnet Mask ? 255.25.252.0 Binary ? 11111111.11111111.11111100.00000000 The route boundary is shown between the 22nd and 23rd bit of the binary. Diagram 3, Activity Determine the appropriate route(s) for the following scenarios: Routes 172.16.32.0/24 172.16.32.0/25 172.16.0.0/22 172.16.0.0/20 172.16.100.0/23 172.16.96.0/20 Network (for all scenarios) Two Switches (S1, S2) Two Multilayer Switches (S3, S4) S1 is connected to S3 S1 is connected to S4 S2 is connected to S3 S2 is connected to S4 Scenario 1 S1 Routes VLAN1-172.16.8.0/24 VLAN2-172.16.9.0/24 VALN3-172.16.10.0/24 VLAN4-172.16.11.0/24 S2 Routes VLAN5-172.16.4.0/24 VLAN6-172.16.5.0/24 VLAN7-172.16.6.0/24 VLAN8-172.16.7.0/24 Scenario 2 S1 Routes VLAN22-172.16.101.0/24 VLAN23-172.16.102.0/24 VLAN24-172.16.103.0/24 VLAN25-172.16.104.0/24 VLAN26-172.17.105.0/24 S2 Routes VLAN30-172.16.30.32/27 VLAN31-172.16.32.64/27 VLAN33-172.16.32.96-27 6.2.5 ? Designing the Addressing Scheme 4 Diagrams Diagram 1, Table The picture depicts five steps, which are used to determine network blocks for the Stadium scenario. Step 1: The designer creates a spreadsheet with columns for each of the network addressing requirements. Using a spreadsheet like this one can make the allocation of addresses easier to plan. The spreadsheet can also be used to record where each block of addresses is implemented in the network. There is a table as follows: Stadium Network ? 172.18.0.0/16 Distribution blocks Wiring Closet Blocks Individual VLANs Point-to-Point Links Step 2: Divide the Class B address into eight separate networks using a /19 mask. These networks are assigned to each block of distribution layer switches to be allocated to the wiring closets. There are only four distribution switch blocks in the current stadium network, so this scheme enables significant growth. The last block, which includes the all ones subnet, is reserved for the wireless users, to allow for roaming. Stadium Network ? 172.18.0.0/16 Distribution blocks ? 172.18.0.0/19 172.18.32.0/19 172.18.64.0/19 172.18.96.0/19 172.18.128.0/19 172.18.160.0/19 172.18.192.0/19 172.18.224.0/19 Wiring Closet Blocks Individual VLANs Point-to-Point Links Step 3: Divide the Distribution Block /19 addresses into eight /22 networks. Depending on the potential for expansion, one or two /22 blocks can be assigned to each closet. None of the wiring closets or WAN sites currently needs this many addresses, but the designer wants to allow for significant expansion in the number of hosts without renumbering the network. Using two /22 blocks instead /21 blocks permits more flexibility in address allocation Stadium Network ? 172.18.0.0/16 Distribution blocks ? 172.18.0.0/19 Wiring Closet Blocks ? 172.18.0.0/22 172.18.4.0/22 172.18.8.0/22 172.18.12.0/22 172.18.16.0/22 172.18.20.0/22 172.18.24.0/22 172.18.28.0/22 Individual VLANs Point-to-Point Links Stadium Network ? 172.18.0.0/16 Distribution blocks ? 172.18.0.0/19 172.18.32.0/19 172.18.64.0/19 172.18.96.0/19 172.18.128.0/19 172.18.160.0/19 172.18.192.0/19 172.18.224.0/19 Wiring Closet Blocks Individual VLANs Point-to-Point Links Step 4: Divide the two /22 blocks into individual /24 blocks so that eight networks can be created. Even though no wiring closet currently needs eight separate networks of 254 hosts, the designer allows for expansion and growth. Stadium Network ? 172.18.0.0/16 Distribution blocks ? 172.18.0.0/19 Wiring Closet Blocks ? 172.18.0.0/22 172.18.4.0/22 172.18.8.0/22 172.18.12.0/22 172.18.16.0/22 172.18.20.0/22 172.18.24.0/22 172.18.28.0/22 Individual VLANs Point-to-Point Links Stadium Network ? 172.18.0.0/16 Distribution blocks ? 172.18.0.0/19 Wiring Closet Blocks ? 172.18.0.0/22 Individual VLANs ? Individual VLANs ? 172.18.0.0/24 172.18.1.0/24 172.18.2.0/24 172.18.3.0/24 Point-to-Point Links Stadium Network ? 172.18.0.0/16 Distribution blocks ? 172.18.0.0/19 Wiring Closet Blocks ? 172.18.4.0/22 Individual VLANs ? 172.18.4.0/24 172.18.5.0/24 172.18.6.0/24 172.18.7.0/24 Point-to-Point Links Step 5: Subdivide the first block in each wiring closet to reserve for further subnetting, for example, to support point-to-point links or cameras. Because using subnet zero may not be supported on older network devices, the designer chooses not to use it in the stadium network. Stadium Network ? 172.18.0.0/16 Distribution blocks ? 172.18.0.0/19 Wiring Closet Blocks ? 172.18.0.0/22 Individual VLANs ? Individual VLANs ? 172.18.0.0/24 Point-to-Point Links ? 172.18.0.0/30 172.18.0.4/30 172.18.0.8/30 Thru 172.18.0.252/30 Diagram 2, Table Subnet Mask ? 255.255.128.0 Effective Subnets ? 2 Maximum Hosts - 32766 Subnet Mask Bits - /17 Subnet Mask ? 255.255.192.0 Effective Subnets ? 4 Maximum Hosts - 16382 Subnet Mask Bits - /18 Subnet Mask ? 255.255.224.0 Effective Subnets ? 8 Maximum Hosts - 8190 Subnet Mask Bits - /19 Subnet Mask ? 255.255.240.0 Effective Subnets ? 16 Maximum Hosts - 4094 Subnet Mask Bits - /20 Subnet Mask ? 255.255.248.0 Effective Subnets ? 32 Maximum Hosts - 2046 Subnet Mask Bits - /21 Subnet Mask ? 255.255.252.0 Effective Subnets ? 64 Maximum Hosts - 1022 Subnet Mask Bits - /22 Subnet Mask ? 255.255.254.0 Effective Subnets ? 128 Maximum Hosts - 510 Subnet Mask Bits - /23 Subnet Mask ? 255.255.255.0 Effective Subnets ? 256 Maximum Hosts - 254 Subnet Mask Bits - /24 Subnet Mask ? 255.255.255.128 Effective Subnets ? 512 Maximum Hosts - 126 Subnet Mask Bits - /25 Subnet Mask ? 255.255.255.192 Effective Subnets ? 1024 Maximum Hosts - 62 Subnet Mask Bits - /26 Subnet Mask ? 255.255.255.224 Effective Subnets ? 2048 Maximum Hosts - 30 Subnet Mask Bits - /27 Subnet Mask ? 255.255.255.240 Effective Subnets ? 4096 Maximum Hosts - 14 Subnet Mask Bits - /28 Subnet Mask ? 255.255.255.248 Effective Subnets ? 8192 Maximum Hosts - 6 Subnet Mask Bits - /29 Subnet Mask ? 255.255.255.252 Effective Subnets ? 16384 Maximum Hosts - 2 Subnet Mask Bits - /30 Diagram 3, Packet Tracer Lab Diagram 4, Hands On Lab 6.2.6 ? Designing a Naming Scheme 2 Diagrams Diagram 1, Image The picture depicts good and bad Internal and External device names given the stadium scenario as follows: Internal device name: W150S-1 - The first switch in the wiring closet in room 150< DC200MD-3R1 - A Multilayer Distribution Switch in the Data Center room 200 on rack 1 DC200WFS-R4 - A windows file server in rack 4 in the Data Center room 200 External device names RM10-LJ1500C - Color Laser Printer in Room 10 DC200-T1-PS - The Team1 Payroll Server in the Data Center room 200 DC200-INT-DS - The Internal DNS server Bad internal names: Cisco2600-FirewallRouter Main NAT Router Bad external names: Win2003-PayrollServer RedHatLinux-CreditCardServer BindDNS-server Diagram 2, Hands On Lab Module 6.3 ? Describing IPv4 and IPv6 6.3.1 ? Contrasting IPv4 and IPv6 Addressing 4 Diagrams Diagram 1, Image The picture depicts the size and availability of addresses for IPv4 and IPv6 addressing as follows: IPv4 32 bits, 4 bytes long 4,200,000,000 possible addressable nodes IPv6 128 bits, 16 bytes: 4 time IPv4 340,282,366,920,938,463,374,607,432,768,211,456 possible addressable nodes Diagram 2, Table The picture depicts the fields that are associated with both an IPv4 and IPv6 frame header, and highlight if the fields are Retained or not Retained in IPv6, have changed position in IPv6, or are a new field in IPv6. IPv4 Version ? Retained IHL ? Not Retained Type of Service ? Name/Position Changed Total Length ? Name/Position Changed Identification ? Not Retained Flags ? Not Retained Fragment Offset ? Not Retained Time to Live ? Name/Position Changed Protocol ? Name/Position Changed Header Checksum ? Not Retained Source Address - Retained Designation Address - Retained Options ? Not Retained Padding ? Not Retained IPv6 Version ? Retained Traffic Class ? Name/Position changed Flow Label ? New Payload Length ? Name/Position changed Next Header ? Name/Position changed Hop Limit ? Name/Position changed Source Address ? Retained Destination Address ? Retained Diagram 3, Table IPv6 Address Representation Format X:X:X:X:X:X:X:X, Where X is a 16-bit hexidecimal field case-insensitive for hexidecimal A,B,C,D,E and F Leading zeros in a field are optional Successive fields of zeros can be represented as :: only once per address Examples 2031:0000:130F:0000:0000:09C0:876A:130B Can be represented as 2031:0:130f::9c0:876a:130b Cannot be represented as 2031::130f::9c0:876a:130b FF01:0:0:0:0:0:0:1 ? FF01::1 0:0:0:0:0:0:0:1 - ::1 0:0:0:0:0:0:0:0 - :: Diagram 4, Image The picture depicts an IPv6 Global Unicast, Multicast, and Anycast Address. Refer to http://www.networksorcery.com/enp/protocol/ipv6.htm for a reasonably accessible description. 6.3.2 ? Migrating from IPv4 to IPv6 1 Diagram Diagram 1, Image Diagram depicts IPv4 packets being ?Tunneled? in IPv6 packets. The IPv4 header is embedded into part of the IPv6 extension header fields 6.3.3 ? Implementing IPv6 on a Cisco Device 5 Diagrams Diagram 1, Image The picture depicts a screen capture of a Routers command prompt, showing an example of a configuration using IPv6 Example 1 Router#config terminal Router(config)#ipv6 unicast-routing Router(coonfig)#int fa0/0 Router(config-if)#ipv6 address 2001:db8:c18:1::/64eui-64 The eui-64 is pointing MAC Address : 260:3EFF:FE47:1530 Example 2 Router#show ipv6 interface fa0/0 FastEthernet0/0 is up, line protocol is up IPv6 is enabled, link-local address is FE80::260:3EFF:FE47:1530 Global unicast address(es): 2001:DB8:C18:1:260:3EFF:FE47:1530 subnet is 2001:DB8:C18:1::/64 [EUI] Joined group address(es): FF02::1 FF02::2 FF02::1:FFDO:FA78 MTU is 1500 bytes ? Router# Diagram 2, Image The picture depicts a screen capture of a Routers command prompt, showing tan example of Cisco IOS IPv6 Name Resolution Options Define a static name for IPv6 addresses Router#config terminal Router(config)#ipv6 host router1 3ffe:b00:ffff:b::1 Router(config)# Configure a DNS server or servers to query Router#config terminal Router(config)#ipv6 name-server 3ffe:b00:ffff:1::10 Router(config)# Diagram 3, Image The picture depicts a screen capture of a Routers command prompt, showing an example of configuring and verifying RIPng for IPv6 Router(config)#ipv6 router rip v6process Router(config-rtr)# ? Router(config-if)#ipv6 rip v6process enable Router(config-if)# Router#show ipv6 rip ? Router#show ipv6 route rip Diagram 4, Image The picture depicts a screen capture of a Routers command prompt, showing an example of RIPng configuration. RouterY RIPng configuration: Ipv6 unicast-routing Ipv6 router rip RT0 Interface Ethernet0 Ipv6 address 2001:db8:1:1::/64 eui-64 Ipv6 rip RT0 enable RouterX RIPng configuration: Ipv6 unicast-routing Ipv6 router rip RT0 Interface Ethernet0 Ipv6 address 2001:db8:1:1::/64 eui-64 Ipv6 rip RT0 enable Interface Ethernet1 Ipv6 address 2001:db8:1:1::/64 eui-64 Ipv6 rip RT0 enable Diagram 5, Activity Module 6.4 ? Chapter Summary 6.4.1 ? Summary 1 Diagram Diagram 1, Slideshow Slide 1 The allocation of IP addresses must be planned and documented in order to: Prevent duplication of addresses Provide and control access Monitor security and performance Support a modular design Support a scalable solution that uses route aggregation A properly designed hierarchical IP addressing scheme also makes it easier to perform route summarization. To support summarization, a network must be designed to have contiguous subnets. If a network is contiguous, all the subnets of the network are adjacent to all other subnets of the same network. Using VLSM eliminates the requirement that all subnets of the same parent network have the same number of host addresses and the same prefix length. Slide 2 Classless routing protocols send the prefix length along with the route information in routing updates. These protocols enable routers to determine the network portion of the address without using the default masks. Because CIDR ignores the limitation of classful boundaries, it enables summarization with Variable Length Subnet Masks (VLSMs) that are shorter than the default classful mask. A complex hierarchy of variable-sized networks and subnetworks can be summarized at various points using a prefix address. To design a flexible, scalable IP addressing scheme, the designer follows a five-step process: Step 1: Plan the entire addressing scheme before assigning any addresses. Step 2: Allow for significant growth. Step 3: Begin with the core network summary addresses and work out to the edge. Step 4: Identify which machines and device require statically assigned addresses. Step 5: Determine where and how dynamic addressing is implemented. Slide 3 The choice of routing protocol must support the VLSM addressing and summarization strategy. EIGRP enables classless summarization with masks that are different from the default classful mask. This type of summarization helps reduce the number of entries in routing updates and lowers the number of entries in local routing tables. The designer follows a step-by-step process to allocate the subnets, beginning with the largest block and working to the smallest. A good network naming scheme makes the network easier to manage and easier for users to navigate. The RFC 1878 states that the practice of excluding all-0s and all-1s subnets is obsolete. Modern software is capable of using all definable networks. Slide 4 Because of its generous 128-bit address space, IPv6 generates a virtually unlimited stock of addresses. IPv6 addresses are written as a series of eight 16-bit hexadecimal digits, separated by colons. The IPv6 host is the equivalent of a registered IPv4 host address. Registered IPv6 host addresses are referred to as global unicast addresses. The transition from IPv4 to IPv6 does not have to be done all at once. The three most common transition methods are: Dual stack Tunneling Proxying and translation 6.4.2 ? Critical Thinking 1 Diagram Diagram 1, Activity Refer to the exhibit. Use the information contained in the diagram to answer the questions. Exhibit Network Two Routers (LAN1, LAN2) LAN1 is connected to LAN2 via Serial link (LAN1: S2/0, LAN2: S0/0) LAN1 is connected to S1 (LAN1: Fa0/0, S1: Wgroup1 IP: 10.10.3.17/28) and has three hosts attached LAN1 is connected to S2 (LAN1: Fa0/1, S1: Wgroup2 IP: 10.10.3.33/28) and has three hosts attached LAN1 is connected to S3 (LAN1: Fa1/0, S1: Wgroup3) and has two hosts attached Router LAN1 IP Addresses Interface ? S2/0 Address ? 10.10.2.1/30 Interface ? Fa0/0 Address ? 10.10.3.16/28 Interface ? Fa0/1 Address ? 10.10.3.34/28 Interface ? Fa1/0 1. The diagram represents the internetwork of the ABC Corporation. The ABC Corporation has decided to add a new workgroup. If the subnetting scheme for the network uses contiguous blocks of addresses, what subnet is assigned to the WGROUP3? 10.10.3.48/28 10.10.3.50/28 10.10.3.56/28 10.10.3.64/28 10.10.3.96/28 2. What is the broadcast address for WGROUP1? 10.10.3.31/28 10.10.3.32/28 10.10.3.48/28 10.10.3.255/28 3. With the new subnet assigned for WGROUP3, what is the first usable IP address that can be assigned to he switch? 10.10.3.48/28 10.10.3.49/28 10.10.3.50/28 10.10.3.63/28 10.10.3.64/29 10.10.3.65/28 4. The IT management has determined that the new subnet for WGROUP3 needs to be broken down into four more subnets. What would the subnet mask be for the four newly created subnets within WGROUP3? 255.255.255.240 255.255.255.248 255.255.255.252 255.255.255.254 255.255.255.255 5. Router LAN1 is advertising a summary route to router LAN2. Which summary address range is used? 10.10.3.0/18 10.10.3.0/19 10.10.3.0/26 10.10.3.16/26