After identifying the remote connectivity requirements and architecture, you are ready to select the individual WAN components.

Hardware Selection

When selecting hardware, use the vendor documentation to evaluate the WAN hardware components. The selection process typically considers the function and features of the particular devices, including their port densities, packet throughput, expandability capabilities, and readiness to provide redundant connections.

Software Selection

The next step is to select the appropriate software features; when using Cisco equipment, the software is the Cisco IOS. As illustrated in Figure below, the Cisco IOS Software has been optimized for different markets, network roles, and platforms. Cisco IOS Software meets the requirements of various markets (enterprise, service provider, and commercial) and places in the network (access, core and distribution, and edge). Suited for access layer devices, Cisco IOS Software T releases support advanced technology business solutions.

Figure: Cisco IOS Software in the Network

Suited for the enterprise core and service provider edge, Cisco IOS Software S releases support voice transport, video, multicast, MPLS VPN, and advanced technologies, such as Layer 2 and Layer 3 VPN and integrated services architecture. Suited for large-scale networks, Cisco IOS Software XR releases provide high availability with in-service software upgrades.

Cisco IOS Software Packaging

Cisco is migrating to using Cisco IOS Packaging to simplify the image-selection process by consolidating the total number of packages and using consistent package names across all hardware products. Figure 4.5 illustrates the various packages available with Cisco IOS packaging.

Figure: Cisco IOS Packaging

Four packages have been designed to satisfy the requirements in base service categories; they are as follows:

■ IP Base: Supports IP data

■ IP Voice: Supports converged voice and data

■ Advanced Security: Provides security and VPN

■ Enterprise Base: Provides enterprise Layer 3 protocols and IBM support.

Three additional premium packages offer new Cisco IOS Software feature combinations that address more complex network requirements:

■ SP Services: Adds SP features, including MPLS, ATM, Secure Shell (SSH) and NetFlow, to the IP Voice package

■ Advanced IP Services: Adds advanced SP services to the Advanced Security package

■ Enterprise Services: Adds advanced SP services to the Enterprise Base package.