Reducing WAN traffic
EDC is mostly a Cisco shop, but Post says he was open to various WAN vendors when he began looking at WAN optimization products; Post says the Cisco product he tested didn't work so well with the 200 or so Macs in his shop. In the end, he chose Silver Peak and says "they didn't accelerate my Mac traffic either, but they didn't break it"; Post also says Silver Peak told him more Mac capabilities are on its roadmap.
Damon Ennis, Silver Peak's VP of customer support and product management, says Silver Peak's Mac acceleration was limited at the time to a certain feature. "We were able to accelerate file copies, but we weren't able to accelerate what we call directory browsing specifically for Apple Macs; that has since been remedied," he explains. Cisco's Weiner says the firm has plenty of customers using Cisco's WAAS for Macs; he noted a recent enhancement to Cisco's WAAS, an HTTP adapter that
| aids Mac traffic.
Post chose an out-of-path deployment, and reconfigured his Cisco Catalyst 3750 series switches for policy-based routing so they would send data to the Silver Peak appliances. "We didn't consider doing it in-path," he explains. "We have tried, as much as possible, to not have a single point of failure in our network design. We have two switches in each location handling the routing of the data. I feel the out-of-path deployment offers more flexibility."
Post chose to implement policy-based routing (PBR) redirection so the appliance intercepts only those packets that have been redirected to it. It accelerates traffic flows that match its Access Control Lists (ACLs); all other traffic passes through the appliance unmodified. But Post's policy-based routing rules were too broad at the outset, which posed a problem. "Originally, we said we wanted everything to go over it. Well, if you send everything, you wind up sending a lot of things you never intended to, such as print jobs from remote offices," he says. "Now we just lock down the IP ranges that [print jobs would send to]."
This was first published in September 2008