To what extent will the public Internet be adequate to handle the burdens of Grid traffic? I recently took that question to Johna Till Johnson, President of Nemertes Research, and she was quick to point out that Grid / Networking discussions are likely to raise questions about the role of MPLS (multi-protocol label switching) in carrying Grid traffic. Here’s what she had to say:“As long ago as about four or five years ago – when I was CTO of Greenwich Technology Partners – we were doing a lot of work with financial services firms, who were some of the early adopters of Grid computing. One of the things we realized was that with what they were trying to do across the WAN … the only way they could actually get the quality of service and reliability and availability they needed was to go with a technology like MPLS. Most of the Grid specs assume an IP network. You have to have some technology that translates between IP and whatever the underpinnings are. If you were going to argue that you wanted to do it over frame relay or ATM, you still need a way to get from IP to that. Another thing that MPLS brings to the table is the availability to set up high bandwidth, low latency high QOS connections between point A and point B – and that’s very important. And even on a private network, you have to look at the traffic pattern. Most private network technologies – including ATM and frame relay – have assumed hub-and-spoke traffic patterns. The servers all live at the center, the users all live at the edges of the cloud, it’s one hop between the user and the server—and everybody’s happy. That’s true if all your traffic is client/server. But if you’re doing peer to peer or Grid, it’s getting closer to an any-to-any traffic pattern. The only way that frame can do that is to start introducing hops, which introduces latency. MPLS can actually allow you at the IP layer to make it any-to-any, and that’s key. So there are 3 basic synergies between MPLS and Grid: 1- Grid assumes that you have a high performance IP network. Most of the service providers have elected to implement their high performance networks on top of MPLS. 2- Grid requires extremely low latency, extremely high QOS, extremely high bandwidth links – MPLS is optimized to be able to deliver that. 3- Grid can be expected to generate any-to-any traffic, and again MPLS can be expected to deliver that. AT&T made a big commitment to MPLS a few years ago – some of the other service providers then bit the bullet. MPLS is very mainstream now.” Technology Industry