As recently as a year and a half ago we both regarded cloud computing as more of a media event than anything that was real and that would impact mainstream IT organizations. That is no longer the case. As we head into 2011 we see the majority of IT organizations adopting one or more forms of cloud computing. Because of this broad interest in cloud computing, we are going to use the next few newsletters to discuss cloud networking.
We use the phrase cloud networking to refer to the functionality that has to be in the network and in the management of the network in order to support cloud computing. One thing that has always been true about networking is that LAN design is fundamentally different than WAN design. If anything, the requirement to support cloud computing increases the differences between LAN and WAN design.
For example, LANs have historically been designed around blazing speed while WANs have traditionally been designed around money. LANs are designed around speed in large part because LAN speeds increase at a dramatic rate. For example, in the late 1990s it was common for Fortune 500 companies to connect servers to their network using a 10Mbps connection. Today it is becoming common to attach servers to the network using 10Gbps connections. That is a factor of 1,000 increase in speed in just over a decade. In contrast, in the late 1990s it was common for Fortune 500 companies to use a 56Kbps WAN link to connect to their typical branch office. Today those companies often use two or three T-1 links to connect to their typical branch office. That means that over the last 10 to 15 years the speed of the WAN links that connect to the typical branch office has increased by a factor that is less than 75.
If we look to the future we see the disparity in LAN and WAN speeds increasing. For example, earlier this year 40Gbps and 100Gbps Ethernet standards were approved. Given the increase in the number of cores per server and the ongoing virtualization of servers, it is reasonable to believe that within the next five years it will be somewhat common for Fortune 500 companies to attach servers to the network using 100Gbps connections. This represents another factor of 10 increase in the speed of server connections. In that same timeframe, it is doubtful if many Fortune 500 companies will increase the capacity of their branch office WAN links by more than a factor of two or three.
Jim recently completed an in-depth report on cloud networking. Given its length, we will publish the report over the next several weeks in five installments. We will also publish a complete copy of the report in mid-December. The first two documents have already been published.
