Summary

This chapter explored changing business climates and their impacts on network architecture, noting that more than ever there is a need and desire for higher productivity from business. IT departments are looking to outsource capabilities that are not core to the company's business.

This chapter also discussed how the trend of convergence is driving new applications onto the IP network and how the requirements and characteristics of the IP network are changing in response. Optimizing the network latency between sites is now very important for collaboration applications including VoIP, videoconferencing, and data collaboration. These applications are also critical in the pursuit of productivity as companies look to create global processes.

Technologies such as Layer 2 and L3 IP/MPLS VPNs allow service providers to develop and scale a single IP network for all services they want to offer (including some legacy services, such as ATM and Frame Relay). Enterprises using these technologies take advantage of the service provider's economy of scale. In addition, choosing L3 IP/MPLS VPN service lets the enterprise effectively outsource the effort required to engineer, operate, and manage capacity in its network core.

Finally, these IP/MPLS VPN services provide a foundation for the convergence of voice, video, and data services. Service providers can now offer services such as remote access, Internet access, hosted IP telephony, IP-based PSTN gateway, content distribution, and storage in a relatively scalable fashion without having to build a custom infrastructure for each customer.

Acme is actively pursuing L3 IP/MPLS VPNs for the following reasons:

• It will not have to invest in a very large engineering effort to redesign its global backbone and regional WAN networks.

• L3 IP/MPLS VPNs will reduce or remove the overhead in managing an interconnecting mesh of circuits in the middle of the network.

• L3 IP/MPLS VPNs will provide a QoS-enabled, latency-optimized foundation for new collaboration applications used on Acme's network.

• Convergence of Acme's Internet connectivity, some extranet connectivity, PSTN voice access, and IP videoconferencing will likely reduce the network access costs associated with individual circuits into each branch office.

Chapters 2 and 3 discuss Acme's key requirements as it evaluates service providers and their services.