WAN Acceleration Configuration

Question

Hello all,
We have purchased WAAS WAE 674 WAN Accelerator's, and I have a question on placement in our network.  I've just recently implemented redundant WAN Lines (DS3's), and now would like to move my WAE674's so that they are accelerating traffic across both WAN lines.
Is this configuration possible with the 2 WAE674's (no inline cards), and WCCP forwarding, and my HQ WAAS controller, or do I have to purchase an additional 2 WAE 674's to accelarate both WAN lines.
Attached is a drawing for what our WAN design network looks like, we are using EIGRP as our routing protocol, and using per destination load sharing, and redistributing our static routes out from our HQ 6509E.
Please let me know if there is more information needed.
Thanks,
Jon

Answer 1

Hi Jon,
Here are the details of GRE and L2 WCCP redirection.
GRE allows datagrams to be encapsulated into IP packets at the WCCP-enabled router and then redirected to a WAE (the transparent proxy server). At this intermediate destination, the datagrams are decapsulated and then handled by the WAAS software. If the request cannot be handled locally, the origin server may be contacted by the associated WAE to complete the request. In doing so, the trip to the origin server appears to the inner datagrams as one hop. The redirected traffic using GRE usually is referred to as GRE tunnel traffic. With GRE, all redirection is handled by the router software.
Layer 2 redirection is accomplished when a WCCP-enabled router or switch takes advantage of internal switching hardware that either partially or fully implements the WCCP traffic interception and redirection functions at Layer 2. This type of redirection is currently supported only with the Catalyst 6500 series switches and Cisco 7200 and 7600 series routers. With Layer 2 redirection, the first redirected traffic packet is handled by the router software. The rest of the traffic is handled by the router hardware. The branch WAE instructs the router or switch to apply a bit mask to certain packet fields, which in turn provides a mask result or index mapped to the branch WAE in the service group in the form of a mask index address table. The redirection process is accelerated in the switching hardware, making Layer 2 redirection more efficient than Layer 3 GRE.
More details here:
http://www.cisco.com/en/US/docs/app_ntwk_services/waas/waas/v441/configuration/guide/traffic.html
Cisco WAAS Software Release 4.0.13 introduces flexibility when using WCCPv2 as the redirection method. It allows configuration of egress method that increases Cisco WAAS deployment alternatives in cases using WCCP iterception. From Cisco WAAS 4.0.13 onward, the WCCP negotiated return is also supported as the egress method. This method allows the Cisco WAE to be deployed on the same subnet as users or servers and provides better support for preservation of the routing path chosen by the network, because the optimized traffic is returned to the redirecting router. The negotiated return egress method also helps ensure compatibility with asymmetric routing, equal-cost multipath (ECMP) load-balancing, and Hot Standby Router Protocol (HSRP) environments. The return traffic egress method is negotiated based on the WCCPv2 configuration on the router and the egress method configuration on the Cisco WAE.
You will find more information here:
http://www-europe.cisco.com/en/US/prod/collateral/contnetw/ps5680/ps6870/prod_white_paper0900aecd806d976a_ps6474_Products_White_Paper.html
Regards.