Inventor of OpenFlow SDN Admits Most SDN Today Is Hype 62
darthcamaro writes "Every networking vendor today is talking about Software Defined Networking (SDN). The basic idea is that the control of the underlying networking hardware is abstracted by software. Martin Casado helped to come up with the whole topic with his 2005 Stanford thesis (PDF). Eight years later after selling his startup Nicira to VMware for $1.2 Billion, Casado sees the term SDN meaning everything and nothing to all people. From the article: '"I actually don't know what SDN means anymore, to be honest," Casado said. Casado noted that the term SDN was coined in 2009 and at the time it did mean something fairly specific. "Now it is just being used as a general term for networking, like all networking is SDN," Casado said. "SDN is now just an umbrella term for, cool stuff in networking."'"
Riding the hype train (Score:4, Informative)
pffffFFF FPGA HA HA HA! (Score:4, Informative)
I'm glad he's laughing all the way to the bank. Gives me room for my new buzz-word compliant technology: Hardware Optimized for Software Systems (HOSS)
Shhhh, it's just ASIC in sheep's clothing.
Re:Software Defined Networking (Score:2, Informative)
You have zero idea what you are talking about. OpenFlow is a wipe of 25 years of networking crap. It does not hand over control to the government anymore then running BGP on your network does. The idea is that within your network, lets say you are a datacenter operator, you can impose policy over a group of switches and routers. They become a dumb packet forwarding engine. Why would you want to do this? Lets say you are an operator selling VMs. You offer an up-sell option of providing a FW or SLB to the customer. Now lets look at this from the point of view of the network. Server - ToR - Core - Services (FW/SLB) - Router. All networks are a variation on that design for the most part. Notice how the FW and SLB are in the path - even if you do not want them to be? With an OpenFlow network you could move those services to the side, in a rack of their own. The controller could then be told that packets from VM X must go thru the FW 1st before going out. Switch sees a flow, ask the controller, hey what should I do? Controller installs a flow_mod, go to firewall - the packet SA/DA is the router but who cares? Shows up at the firewall, stuff happens then gets sent to the router. Someone buys the FW option - order page tells the controller and it just happens. 4096 VLANs limit? Whats that? Build a full L2 10/8 network. You can enforce the rules that host 1 at 10.0.0.20 and host 2 at 10.0.0.21 cannot talk at the controller level. No ACLs. Broadcast packets? What are those? You send an ARP for something and the controller answers, no need to flood.
Check out www.bigswitch.com.
Re:Software Defined Networking (Score:2, Informative)
congratulations. you've just substantially raised the complexity of the installation and gained absolutely nothing
in terms of performance, or policy expression, or security.
have fun masturbating
Re:Software Defined Networking (Score:2, Informative)
oh yes, and drastically reduced the fault tolerance
Virtual circuit network (Score:5, Informative)
OpenFlow is basically a way to turn a packet network into a rather dumb virtual circuit network. It works something like Tymnet, circa 1971. In Tymnet, all the virtual circuits were set up by a "supervisor" computer, which told each node where each flow was supposed to be forwarded. The supervisor also handled authentication, but data packets didn't have to pass through the supervisor once the connection was set up. That's what OpenFlow does, mostly. The first packet of each new "flow" (IP/port/IP/port set, usually) is sent to Master Control, which decides whether that flow will be allowed. Master Control can also choose to monitor the flow. The implications are obvious.
DOCSIS 3, the cable modem traffic control architecture, can potentially do most of the same things, and offers better control over bandwidth. DOCSIS 3 tends to be run more to control users than to maximize throughput, but that's a marketing issue. (If your cable connection is throttling something, the commands to do it were probably sent to a DOCSIS node.) There's good QoS and fair queuing stuff in DOCSIS 3, but it's not always used intelligently. DOCSIS is less intrusive than OpenFlow; the nodes are sent rules to enforce, but there's no need to get permission of Master Control for every new flow.
The rest of "software defined networking" seems to involve adding another layer of indirection to Ethernet addresses so they can be moved around within the data center. ("There is no problem in computer science that cannot be solved by adding another layer of indirection.") That's a reasonable network management tool, but it's not exactly a profound concept.
Re:dunno (Score:4, Informative)
Re:So we aren't going to be able to replace... (Score:5, Informative)
SDN in practise just means, networking things (private networks, VPNs, loadbalancers, etc.) have an API so they can be automated.
So when you need to scale out, because your website has more visitors during the day then you don't just get new VMs but those VMs also get connected to the right networks or extra load balancers gets added as well.
The software in software defined networking, is the application specific software. That application can be that website as mentioned above or something completely different.
For example Google uses their self-developed software to reserve bandwidth for their different applications and data-replication jobs and handle link failover on the WAN-links between their datacenters.
Because they used OpenFlow their were able to save money on their WAN-links because they get better utilization than traditional methods. They have normal Google servers that 'directly' configure the forwarding tables.