Chapter 4: IP Routing Designs

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Chapter 4 IP Routing Designs

• Designs That Include IP Routing
• Essential IP Routing Design Concepts
• Data Protection on Unsecured Segments
• IP Routing Design Optimization

2
An IP Routing Example
3
IP Routing Design Review

• Amount and confidentiality of data
• Network growth plans
• Existing routers, connections, and protocols
• Application response times
• Reliability

4
IP Routing Design Decisions

• Types of connections
• Connection technologies
• Dynamic routing vs. static routing table
• Redundant routers and connections
• Packet filters
• Authentication and encryption

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Edge of Network Scenario
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Multiple Location Scenario
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Single Location Scenario
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Design for Multiple Locations
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Integrating Routers

• Router network interfaces
• Router IP addresses
• Router interface connections
• Local area network (LAN)
• Demand-dial
• Router security

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Unicast Routing

• Unicast routing tables
• Static routing
• Dynamic routing

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Static Routing

• Reduces network use
• Hides private network structure
• Requires more administration time
• Does not support frequent network path changes
• Supports demand-dial interfaces
• Does not support redundant route paths

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Default Route Entries

• Reduce routing table entries
• Specify a single route path
• Disadvantage use the default path even for
  invalid paths

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Autostatic Route Entries

• Combine the best features of static and dynamic
  routing
• Exchange entries at intervals
• Can minimize network congestion
• Can be used with many dynamic IP routing
  protocols

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RIP for IP

• A dynamic routing protocol
• Supported by most routers
• Supports network diameters less than 15
• Allows using Routing Information Protocol (RIP)
  for IP version 2 with
• Classless Interdomain Routing (CIDR)
• Variable Length Subnet Mask (VLSM)
• Multicast traffic
• Mutual authentication

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OSPF Routing

• A dynamic routing protocol
• Supported by Routing and Remote Access
• Uses link state database
• Supports diameters larger than 15

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OSPF Routing Design

• Should be arranged in top-down hierarchy
• Includes Open Shortest Path First (OSPF)
  autonomous system
• Includes groups of routers called areas
• Includes a backbone area connecting all other
  areas
• OSPF networks reside within an area

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Multicast Routing

• RIP for IP version 2 can multicast.
• Internet Group Messaging Protocol (IGMP) can be a
  multicast proxy.
• Proxy mode interface
• Router mode interface

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DHCP Relay Agent

• Reasons to use Dynamic Host Configuration
  Protocol (DHCP) Relay Agent
• DHCP traffic forwarding options
• Broadcast traffic
• DHCP/ Boot Protocol (BOOTP) forwarding
• DHCP Relay Agent

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IP Filters

• Included in Routing and Remote Access
• Allow you to specify filters on router interface
• Filter source or destination address
• Filter IP protocol number
• Combine filters

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Router Identification

• Routing protocol methods
• Plain text passwords
• RIP for IP peer security
• RIP for IP neighbors
• Internet Protocol Security (IPSec)
• Demand-dial

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Router Data Protection

• Virtual private network (VPN) tunnels
• Use Point-to-Point Tunneling Protocol (PPTP) or
  Layer 2 Tunneling Protocol (L2TP)/IPSec tunnels
• Use for edge of network designs
• IPSec tunnels
• Use transport mode or tunnel mode
• Can be used alone or with L2TP

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Optimizing IP Routing

• Configure RIP for IP routers to use RIP
  neighbors.
• Use persistent connections.
• Add connections.
• Add router interfaces.
• Add routers.

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Chapter Summary

• Routing and Remote Access in Windows 2000
  provides routing.
• Base designs on a review.
• Determine where to place routers.
• Determine unicast or multicast routing.
• Use DHCP Relay Agent.
• Consider data protection.