Router Vendors Look To Linux
At least two optical equipment vendors think so: they're looking to use it as the operating system in their next-generation routers and switches. There's just one problem: adapting the kernel to handle carrier class capacity may be harder than first thought.
In April of 1999, Nbase-Xyplex Inc. http://www.nbase.com, a company owned by MRV Communications Inc. http://www.mrv.com, announced the OSR8040 Linux switch-router -- a product designed to compete in the Internet core with products from Cisco Systems Inc. http://www.cisco.com and Juniper Networks Inc. http://www.juniper.com
It sounded cool. After all, Linux has the potential to deliver huge benefits to service providers: using an open source router kernel would give them the freedom to develop their own applications -- such as billing, or service provisioning. Moreover, they could swap their apps with other service providers, upgrade the software as and when they wanted to (not when the router vendor chose to release a new version), and reap the benefits of the vast, friendly, free network of Linux support advice available on the Internet.
But a year later the OSR8040 from Nbase-Xyplex is still not commercially available. What's the hold up? It's really quite simple. Linux was built to run on PCs. While it may be great for Web servers, it doesn't scale well for routers.
"Linux can't run with the big Unixes or BSD derivatives," says David Newman, president of Network Test, an independent testing lab http://www.networktest.com. "Linux's IP stack doesn't scale to huge levels for a couple of reasons -- its packet capture code is kind of crude, and the OS itself offers a limited number of file descriptors, which limits the number of things it can do at once."
While the Linux kernel is constantly being improved by developers around the globe, it's still not robust enough today to handle thousands and tens of thousands of connections, adds Newman.