The BIG-IP® WAN Optimization Manager™ systems work in pairs on opposite sides of the WAN to optimize the traffic that flows between them. A simple point-to-point configuration might include WAN Optimization Manager (WOM®) running on a BIG-IP system in one data center, and a second BIG-IP WOM running in another data center on the other side of the WAN. Other configuration possibilities include point-to-multipoint (also called hub and spoke) and mesh deployments.
The following illustration shows an example of the flow of traffic across the WAN through a pair of BIG-IP WOM devices. In this example, traffic can be initiated on both sides of the WAN.
The BIG-IP WOM as an endpoint. From the standpoint of each BIG-IP WOM, it is the local endpoint. Any BIG-IP WOM with which the local endpoint interacts is a remote endpoint. After you identify the endpoints, communication between the WOM pair takes place in an iSession™ connection between the two devices. When you configure the local WOM, you also identify any advertised routes, which are subnets that can be reached through the local endpoint. When viewed on a remote system, these subnets appear as remote advertised routes.
To optimize traffic, you select the applications you want to optimize, and BIG-IP WOM sets up the necessary virtual servers and associated profiles. The system creates a virtual server on the initiating side of the WAN, with which it associates a profile that listens for TCP traffic of a particular type (HTTP, CIFS, MAPI, FTP). The local BIG-IP WOM also creates a virtual server, called an iSession listener, to receive traffic from the other side of the WAN, and it associates a profile that terminates the iSession connection and forwards the traffic to its destination. For some applications, the system creates an additional virtual server to further process the application traffic.
The default iSession profile, which the system applies to application optimization, includes symmetric adaptive compression. Also by default, symmetric data deduplication is enabled.
The Quick Start screen for WAN optimization provides all the settings you need to configure WAN Optimization Manager™ (WOM®) on one side of the WAN. After you have set up the BIG-IP® WOM® systems on both sides of the WAN, you can begin optimizing the application traffic you specify. An important advantage of configuring WOM using the Quick Start screen is that the system automatically selects TCP parameter settings based on the hardware. If you do not use the Quick Start screen, the system uses the generalized default TCP settings, which might not be optimal for your hardware.
The Quick Start screen is for the initial BIG-IP WOM setup. To change the settings for any WOM objects after you have completed the initial configuration on the Quick Start screen, use the screen that pertains to that object. For example, to change the settings for the local endpoint, use the Local Endpoint screen.
|LAN VLANs||Select the VLANs that receive incoming LAN traffic destined for the WAN.|
|WAN VLANs||Select the VLANs that receive traffic from the WAN through an iSession™ connection.|
The system creates the necessary virtual servers and associated profiles to optimize the selected application traffic, as indicated by the green check marks in the Optimizations Enabled column on the Quick Start screen. If your network supports IPv6, the BIG-IP WOM automatically creates virtual servers for both IPv6 and IPv4 networks, and uses the appropriate virtual server based on the IP addressing in your network.
For some applications, such as HTTP and MAPI, the system creates a virtual server only for initiating traffic. For other applications, such as CIFS and FTP, the system creates two virtual servers: one to initiate traffic destined for the other side of the WAN and another to receive traffic from the other side of the WAN, after the traffic is terminated by the iSession terminating virtual server.
When you configure WAN Optimization Manager™ (WOM®) using the Quick Start screen, you can specify IPsec encapsulation for outbound iSession™ traffic. The BIG-IP® WOM system automatically creates the necessary virtual servers for optimizing TCP traffic. If you also want to send secured and encrypted non-TCP traffic, you can create a forwarding virtual server and associate an iSession profile to send non-TCP traffic through the iSession over IPsec tunnel.
You can use the rate shaping feature of the BIG-IP® system to enforce a throughput policy on incoming traffic. Throughput policies are useful for prioritizing and restricting bandwidth on selected traffic patterns.
The rate shaping feature works by first queuing selected packets under a rate class, and then dequeuing the packets at the indicated rate and in the indicated order specified by the rate class. A rate class is a rate-shaping policy that defines throughput limitations, and a packet scheduling method to be applied to all traffic handled by the rate class.
You configure rate shaping by creating one or more rate classes and then assigning the rate class to a packet filter or to a virtual server. The BIG-IP system packet filters are based on the Berkeley Software Design Packet Filter (BPF) architecture. Alternatively, you can use the iRules® feature to instruct the BIG-IP systems to apply a rate class to a particular connection.