Shortest Path Bridging (SPB)

For those of you who have been around long enough to know that “token ring” (not to be confused with Tolkien Ring or something a guy gives a girl when he’s not ready to get married but wants her to stick around), you are going to LOVE SPB! For those of you newer to networking, you’ll love it too, but perhaps not with the same level of appreciation.

And yes, I am almost afraid to admit that I understand that ArcNet is not a type of basketball shot, and that at one time ATM was NOT a machine that you used to withdraw funds from your account.  But maybe that explains why I am so excited about the new era of networking that is known as "Fabric".

Over the years we have seen the number of Data Link and Network Layer protocols whittled down to Ethernet and IP, while the number of routing protocols (RIP, RIPII, OSPF) and Transport Layers (UDP, TCP, RDP) increased to address the advent of new applications emerging.  I stand in awe of the folks on the IETF along with their ingenuity to extend IPV4 well past its expected lifespan through creative methods devised via subnetting, use of private subnets, NAT, spoofing, etc.  You really need to take your hat off to these creative individuals. Talk about making the most of something!

That being said, deploying a network in the era of the "Internet of things", is to say the least quite challenging.  Those of you who are tasked with maintaining the IP Addressing and extending the network to support the vast number of users and devices in a secure fashion are to be commended.  I sympathize with all of you who have to carve out an IP range, negotiate for a maintenance window to deploy a new application, and then have to spend late night hours programming each switch (ingress/egress) with the IP addresses that you manually input. Hoping that you input each of the 32 bits correctly without a fat finger or dyslexic moment.  Some of you are so adept at writing the scripts that are executed at each point that you remind me of those irritating folks in typing class (yes, back then it was typing, not keyboarding) that could type 100 words per minute without a mistake.  Quite unnatural, even freakish I’d say.  Anyway, back to networking.  I almost forgot, multicast.  Great IDEA! But woe to those of you with Cisco or Enterasys networks, should you be asked to deploy.

Welcome SPB!
I can only imagine that some very bright, out of the box thinkers must have been sitting in a room with a really big white board pondering these issues.  Or perhaps they sat in a brew house discussing them over a few beers when they decided to make a list.  This list consisted of all the networking protocols, and in another column all the services these protocols performed and in yet another column the problems the protocols were created to solve. Finally in the last column, all the challenges associated with them.  I can just see them sitting back and asking themselves,  "What if we could create a NEW networking standard that could do all the good things, and eliminate the problems?" …hmmmm – the birth of SPB!

SPB is a scalable (it can grow really big!), extensible (it can support new devices, applications, etc.), secure (you can’t hack what you can’t see), fast (lots of high speed links), resilient (it can have a link or two or three…go down and your packets still get around), and simple (zero touch cores, endpoint only provisioning, no more scripts, maintenance windows, or all-nighters!).  For those of you who want to take a deep dive you can see Paul Unbehagen (Co-Author) giving an overview of the protocol in a 30-minute YouTube video:

Avaya Fabric Connect SPB Deep Dive

For the rest of us, here are the common denominators of networking today:

Layer 1:  Cabling standards:
Copper Twisted Pair (Cat 6e).  Yes, we still run into Cat 5e and via the use of ingenuous designs we can also ride over Cat 3 but….
- Fiber:  Single Mode / Multi-Mode with SC or LC connectors
- Air Waves:  802.11ac is the current flavor of WiFi.  In a very short time, everyone will be using ac. Since the standard is relatively new, you will see a lot of legacy WiFi with 802.11n, but manufactures are now offering APs that have software upgradeable options.

Layer 2:  Ethernet  10/100/1000 
There were a number of competing standards in the early days but Ethernet was declared the winner a long time ago (at least in networking years).

Layer 3:  IP Won in the Enterprise
There were also a number of competing standards in the early days but IP was declared the winner in that arena. Anyone shedding a tear over IPX or AppleTalk?

However, in the carrier space there have been protocols that we mere mortals rarely encounter. One of these protocols is IS-IS that is renowned for scalability.  (This is a hint)

A new standard has emerged that blends the best of L2, L3 and the concept of virtualization, that standard is ….SPB.  It takes the best of all the rest and combines them to create a virtualized network with ease of configuration and inherent scalability through the use of IS-IS in the core of the Fabric.  Ethernet endpoints can now be added to the Fabric by simply configuring the ingress (Entry point) port and Egress (Exit Point).  The Fabric will automatically determine the best and shortest path through the network automatically.

How?  The intermediate devices (switches with Fabric and SDN) communicate and negotiate to provide the Shortest Path with the best available service to Bridge the two Points together = SPB.

How?  Well, the devices talk amongst themselves and exchange information about who knows about what and they maintain tables of the paths, their speed and link states.

SPB uses the concept of VLANs but at a whole new level.  While VLANs imposed a limit of 4096 VLANs, SPB allows over 16 Million VRFs (Virtual Route Fabric) to be created and SPB devices are provided VID (Virtual InDentifiers).  Those of you who are familiar with Routing protocols and the concept of Link States will be right at home with SPB, because as I previously stated, SPB took the best of the rest, eliminated the negative components, and combined them to create a scalable (you can grow it really, really big across large geographic areas), secure (you can’t hack what you can’t see),  extensible (add any protocol or application you need to your network – event ones that haven’t been written yet), and simple (a few technicians can configure and run an enormous, extremely complex network all by themselves, easily).  One of the most gratifying aspects of the protocol is that it gives the technical staff back their life!  

Yes, their life.

How you ask?  Because they don’t have to spend their holiday weekends rolling out new applications or adding another site. The Management tools provide an easy to use interface that enables the users to become involved as much or as little as they want.

Avaya Fabric - Simplifying Networking

In Summary SPB is:
• Plug and Play
• Ethernet attached
• Has a Symbiotic relationship with IP and Ethernet
• Scalable
• Uses VRF offering (16 Million)
• Creates a seamless, consistent, contextually relevant experience
• Offers One protocol that does all the routing and switching at once
• With no complexity
• Edge Only Configuration
• Protection for applications

All with major:
• Cost reduction to build and maintain network – 20-30% savings in hardware, Rackspace,
• Reduction in time to deploy. – reduce provisioning 80%
• Operational expense saving of 87% through reduction in time to service and time to deploy
• 37% of all network outage is a result of human error at the core
• 5 9’s reliability (less than 4 minutes downtime annually)
• Usage of ISID 802.1ah protocol for simplicity

SPB Offers support that includes:
• 16 million services
• A Network that becomes invisible/No IP Visibility
• 1 Hop through the Fabric to the Internet for low latency
• Integrated Routing & Switching
• A Fabric that is a single state machine
• Isolation of services
• Simple endpoint provisioning
• Flexible – Multiple Services
• Secure – Separation of Networks
• Zero Touch Core
• Fabric Attach
• Zero Touch Edge
• No Clients
• The Endpoint/Client connections trigger auto configuration of ISID, VLANs, port membership, etc.
• Automatically, authenticated, authorized, and provisioned to automatically connect the client to the required services.

SPB is the foundation for:
• SDN
• Automation
• A network that does not require tuning every day.

And as such, it is going to be one of the key elements that will enable your organization to keep up with the pressures being exerted on your team.  The pressure to provide new services by your customers, employees, business initiatives, applications, compliance regulations, security initiatives, etc.  So, strap in and get ready for a fun ride with a driving force in the next wave of the "Internet of Things".

Stay tuned for the next article on SDN:  The deployment tool that makes network provisioning a 15 minute task rather than a maintenance window.

Fabric

The term Fabric and Fabric Networking is used a lot these days by almost all vendors, the question is:  What does that actually mean?

The industry came up with the term “Fabric” to describe networking technologies that allow networking gear (Switches & L3 Switches) to connect in a way to achieve a mesh topology.  If you think of a real piece of cloth (fabric) the threads create a mesh. Mesh topology has always been identified as the ideal for resiliency; however, in the past, due to cost and protocol limitations this has been difficult, if not impossible to achieve. Traditional networking connectivity had only a few connections between devices.  Resiliency typically meant two trunks, maybe three, especially in the WAN.  Recent advancements in technology now permit intelligent switches to be hyper-connected and thus the term “Fabric” emerged to describe this new intelligent network.  When you hear the term “Fabric” think more than “lots of links”.   This new fabric is intelligent and scaleable. 

What does it mean to have an intelligent network?  It means that the devices that comprise the network fabric are managed and seen as an integrated whole rather than a series of interconnected devices.  The network administrator has the ability to define policies for any device, application, job classification, individual, etc.  These policies can intersect and the fabric will automatically adjust to provide that object the level of service that the policies dictate.  There is no longer a need to provision each switch and port whenever a new user, device, or application is added to the organization.  An administrator will create the policy, provision the endpoints and the fabric will auto learn and provision itself to meet the requirements. 

This capability is enabled via new technologies and protocols that have been defined and ratified by the IEEE (Institute of Electrical and Electronics Engineers) and IETF (Internet Engineering Task Force).   To achieve end to end fabric, the network will need to have intelligent devices capable of SPB (Shortest Path Bridging), and SDN (Software Defined Networks).  TRILL ("Transparent Interconnection of Lots of Links") is another standard that was developed in an attempt to achieve full fabric networking.  While it does meet some of the requirement for fabric, it is intended only for the core and does not reach to the edge so that the promise of full fabric and SDN can never be realized.

This article is the first in a series of the new state of the network. The next article will be on the topic of Shortened Path Bridging (SPB).