Today's modern Wide Area Networks (WANs), such as MPLS networks, provide much more than just a framework for information transport. Many large enterprises use a networking infrastructure provided by a service provider (SP) and employ some or all of its services on the network. In fact, the recent consolidation trend of servers, storage and applications relies more heavily on the WAN to provide an intelligent path for connecting users in remote offices to the core and data center. Using the provided services, the enterprise can:

• Route traffic (routing/VPN)
• Assure and maintain the network's connectivity (resilience/Traffic Engineering)
• Prioritize and shape the traffic (QoS/Traffic Engineering)
• Monitor traffic, applications, sessions and users on the network (monitoring)
• Secure traffic (VPN/encryption)
• Protect the network (Firewall/IDS)
• Pay per type of traffic and usage (billing/accounting)

Deploying WAN optimization devices in a modern enterprise WAN can present integration challenges, especially when advanced services such as the ones listed above are used. Most WAN optimization devices tunnel the compressed traffic between appliances, changing the original packet header and payload. Any WAN service that relies on the original packet header information will not be able to function once the header and payload have been hidden inside the tunnel traffic. Expand Networks' Accelerator was designed to seamlessly integrate into modern WAN's through a combination of features and functions.