Keeping up with emerging start-ups in the software-defined networking (SDN) market is becoming a full-time job.
Most of the SDN buzz centers on Layer 2/3 networking. That’s what is dominating the agenda at this week’s Open Networking Summit. However, a smaller group of start-ups are focusing on SDN at Layer 4-7.
Today network engineers virtualize Layer 4-7 services by deploying software images of leading network appliance vendors on x86 server hardware. These software images, often labeled as virtual appliances, are available from several WAN optimization and application delivery controllers vendors, for instance.
Enterprises achieve scale with this approach by adding more virtual appliance images. However, bottlenecks will remain inevitable.
“The real problem here is the operating system itself,” said Steve Georgis, CEO of LineRate Systems, a new start-up that specializes in virtual Layer 4-7 services. “Linux was designed to be a general purpose OS, not a network OS. The network stack spends a lot of time managing network connections. Every time you add a network connection, the amount of time that stack spends on managing connections grows and it can spend less and less time managing the actual packets. As you scale up to the thousands of simultaneous connections, the operating system is left with very little time to do any real work. You run into pretty dramatic bottlenecks and throughput falls off quickly.”
Some enterprises will eliminate these bottlenecks by attaching a network acceleration module to a server to offload some of the processes that can overwhelm a server’s CPU, like TCP termination on an application delivery controller. Unfortunately, once you add these modules, you are pretty limited in how you deploy Layer 4-7 services. You can ‘t stand-up a new application delivery controller just anywhere. You have to put it on a server with the module.
LineRate Systems emerged from stealth mode today with a new acronym: SDNS (Software-defined network services). Its technology, the LineRate Operating System (LROS), is a re-engineered network stack for a Linux kernel that enables wire-speed throughput on a Linux server. Georgis claims that this can deliver 20 to 40 Gbps of network processing capability on a commodity x86 server with extremely high session scalability (hundreds of thousands of full-proxy Layer 7 connections per second and more than 2 million concurrent active flows).
LineRate has done some additional software engineering under the hood, including some work to eliminate blocking among cores within a multi-core CPU.
On top of this LROS, LineRate is offering LineRate Proxy, a product that operates as a full proxy for Layer 4-7 services on commodity server hardware. It includes several features: load balancing, content switching and filtering, SSL termination/origination, ACL and IP filtering, TCP optimization, DDoS blocking and an IPv4/IPv6 translation gateway.
Georgis said LineRate will develop more functionality in security, network monitoring, and Layer 7 switching in the future. The company is initially targeting cloud providers, but it expects to develop an enterprise market, particularly among companies that are building private clouds.