Other Applications of Policy Routing

One practical application of policy routing is its use with firewalls. Firewalls are devices that apply security requirements to traffic. Firewall implementations include packet filtering, authentication, and encryption. Depending on the network setup, administrators might want to direct some or all incoming (or outgoing) traffic toward a firewall device, as shown in Figure 8-9. Figure 8-9. Incoming or Outgoing Traffic Can Be Routed to a Firewall   An applicable situati..

Determining All Subnets of a Network—Binary

Another common question, typically simply a portion of a more challenging question on the CCIE written exam, relates to finding all subnets of a network. The base underlying question might be as follows: Given a particular class A, B, or C network, and a mask/prefix length used on all subnets of that network, what are the actual subnet numbers? The answers can be found using binary or using a simple decimal algorithm. This section first shows how to answer the question using..

Basic Foundation Identity Concepts

Almost all network-connected applications support some basic form of identity. Most often this takes the form of a username and a password. By proactively checking for bad passwords, educating users about choosing good passwords, and giving preference to applications with some form of secure transport (for example, Secure Shell [SSH]), you can achieve reasonable security for most systems. This chapter discusses more advanced identity systems that usually benefit very specific..

Associate Secondary VLANs to a Primary VLAN SVI

On switched virtual interfaces, or VLAN interfaces configured with Layer 3 addresses, you must configure some additional private VLAN mapping. Consider a different example, where the SVI for the primary VLAN, VLAN 200, has an IP address and participates in routing traffic. Secondary VLANs 40 (an isolated VLAN) and 50 (a community VLAN) are associated at Layer 2 with primary VLAN 200 using the configuration in Example 17-3. Primary VLAN 200 can forward traffic at Layer 3, b..

Defining DHCP Configuration Options

You can configure a wide variety of DHCP parameters for configuring client workstations: Router1#configure terminal Enter configuration commands, one per line.  End with CNTL/Z. Router1(config)#ip dhcp pool ORAserver Router1(dhcp-config)#host 172.25.1.34 255.255.255.0 Router1(dhcp-config)#client-name bigserver Router1(dhcp-config)#default-router 172.25.1.1 172.25.1.3 Router1(dhcp-config)#domain-name oreilly.com Router1(dhcp-config)#dns-server 172.25.1.1 10.1.2.3..