As networking trends yo-yo between layer-3 and layer-2, different protocols have emerged to address issues with large layer-2 networks. Protocols such as Transparent Interconnection of Lots of Links (TRILL), Shortest Path Bridging (SPB), and Virtual Extensible LAN (VXLAN) have emerged to address the need for scalability at Layer2. Cloud scalability, spanning tree bridging issues, and big broadcast networks start to become a problem in a large data center or cloud environment.
To figure out if things like TRILL is a solution for you, you must understand the problem that is being addressed by TRILL. The same goes for the rest of the mentioned protocols. When it boils down to it the reason for looking at such protocols is you want high switching capacity, low latency, and redundancy. The current de facto standard of Spanning Tree Protocol (STP) simply is unable to meet the needs of modern layer2 networks. TRILL addresses the problem of STP’s ability to only allow one network path between switches or ports. STP prevents loops by managing active layer -2 paths. TRILL applies Intermediate System-to-Intermediate System protocol (IS-IS), which is a layer3 routing protocol translated to Layer 2 devices.
For those who say TRILL is not the answer things like SPB also known as 802.1aq, and VXLAN are the alternatives. A presentation at NANOG 50 in 2010 addressed some of the SPB vs TRILL debate. This presentation goes into great detail on the differences between the two.
The problem, which is one most folks overlook, is that you can only make a layer 2 network so flat. The trend for a while, especially in data centers, is to flatten out the network. Is TRILL better? Is SPB better? The problem isn’t what is the better solution to use. What needs to be addressed is the design philosophy behind why you need to use such things. Having large Layer2 networks is generally a bad idea. Scaling issues can almost always be solved by Layer-3.
So, and this is where the philosophy starts, is TRILL, SPB, or even VXLAN for you? Yes, but with a very big asterisk. TRILL is one of those stop-gap measures or one of those targeted things to use in specific instances. TRILL reduces complexity and makes layer-2 more robust when compared to MLAG. Where would you use such things? One common decision of whether to use TRILL or not comes in a virtualized environment such as VSPHERE.
Many vendors such as Juniper, have developed their own solutions to such things. Juniper and their Virtual Chassis solution do away with spanning tree issues, which is what TRILL addresses. Cisco has FabricPath, which is Cisco’s proprietary TRILL-based solution. Keep in mind, this is still TRILL. If you want to learn some more about Fabric Path this article by Joel Knight gets to the heart of Fabric path.
Many networks see VXLAN as their upgrade path. VXLAN allows layer 2 to be stretched across layer 3 boundaries. If you are a “Microsoft person” you probably hear an awful lot about Network Virtualization using Generic Routing Encapsulation (NVGRE) which can encapsulate a layer two frame into IP.
The last thing to consider in this entire debate is how does Software Defined Networking (SDN) play into this. Many folks think controllers will make ECMP and MLAG easy to create and maintain. If centralized controllers have a complete view of the network there is no longer a need to run protocols such as TRILL. The individual switch no longer makes the decision, the controller does.
Should you use Trill, VXLAN, or any of the others mentioned? If you have a large Layer-2 virtualized environment it might be something to consider. Are you an ISP, there is a very small case for running TRILL in anything other than your data center. Things such as Carrier Ethernet and MPLS are the way to go.
I had a client learn a lesson they should not have had to this evening. The client has had several key servers hosted at a small data center for several years now. These were managed servers the data center took care of. Things like new hard drives were the responsibility of the data center so the client rarely paid attention to these machines. As many of you know a server can spin for years and it is just forgotten about.
Tonight these servers come under a very heavy Denial of Service (DDoS) attack. Fifteen plus Gigs come to bear at client’s servers for an extended time. The client is unable to reach the data center NOC, nor do any of his contacts work. The servers are knocked offline. 4 hours later the client finally receives an e-mail from the data center saying they unplugged the client’s router because it was taking down their (the DC’s) own network. After asking to have a call from a manager client finds out the DC has restructured and dropped many of their co-location and other hosting services. Their multiple 10 gig pipes have been reduced to one, and many clients have left. The manager says they have re-focused their business to focus on things such as OLED screens, and other things totally unrelated to running a data center. The hosting they do have left “pays the bills” so they can have a place to do research.
The client has redundancy so they are not dead in the water. However, this redundancy was only supposed to be for a short term duration due to costs. The lesson learned is to keep in contact with your vital members. Call up your sales person once or twice a year and see how things are going. Keep in contact with key folks at the company. If they are on LinkedIn add the company. If their focus appears to change or they go silent do some leg work to find out what’s going on.
One of the most asked questions which comes up in the xISP world is “How do I learn this stuff?”. Depending on who you ask this could be a lengthy answer or a simple one sentence answer. Before we answer the question, let’s dive into why the answer is complicated.
In many enterprise environments, there is usually pretty standard deployment of networking hardware. Typically this is from a certain vendor. There are many factors involved. in why this is. The first is total Cost of Ownership (TCO). It almost always costs less to support one product than to support multiples. Things like staff training are usually a big factor. If you are running Cisco it’s cheaper to train and keep updated on just Cisco rather than Cisco and another vendor.
Another factor involved is economies of scale. Buying all your gear from a certain vendor allows you to leverage buying power. Quantity discounts in other words. You can commit to buying product over time or all at once.
So, to answer this question in simple terms. If your network runs Mikrotik, go to a Mikrotik training course. If you run Ubiquiti go to a Ubiquiti training class.
Now that the simple question has been answered, let’s move on to the complicated, and typically the real world answer and scenario. Many of our xISP clients have gear from several vendors deployed. They may have several different kinds of Wireless systems, a switch solution, a router solution, and different pieces in-between. So where does a person start?
We recommend the following path. You can tweak this a little based on your learning style, skill level, and the gear you want to learn.
1.Start with the Cisco Certified Network Associate (CCNA) certification in Routing and Switching (R&S). There are a ton of ways to study for this certification. There are Bootcamps (not a huge fan of these for learning), iPhone and Android Apps (again these are more focused on getting the cert), online, books, and even youtube videos. Through the process of studying for this certification, you will learn many things which will carry over to any vendor. Things like subnetting, differences between broadcast and collision domains, and even some IPV6 in the newest tracks. During the course of studying you will learn, and then reinforce that through practice tests and such. Don’t necessarily focus on the goal of passing the test, focus on the content of the material. I used to work with a guy who went into every test with the goal of passing at 100%. This meant he had to know the material. CompTIA is a side path to the Cisco CCNA. For reasons explained later, COMPTIA Network+ doesn’t necessarily work into my plan, especially when it comes to #3. I would recommend COMPTIA if you have never taken a certification test before.
2.Once you have the CCNA under your belt, take a course in a vendor you will be working the most with. At the end of this article, I am going to add links to some of the popular vendor certifications and then 3rd party folks who teach classes. One of the advantages of a 3rd party teacher is they are able to apply this to your real world needs. If you are running Mikrotik, take a class in that. Let the certification be a by-product of that class.
3.Once you have completed #1 and #2 under your belt go back to Cisco for their Cisco Certifed Design Associate (CCDA). This is a very crucial step those on a learning path overlook. Think of your networking knowledge as your end goal is to be able to build a house. Steps one and two have given you general knowledge, you can now use tools, do some basic configuration. But you can’t build a house without knowing what is involved in designing foundations, what materials you need to use, how to compact the soil, etc. Network design is no different. These are not things you can read in a manual on how to use the tool. They also are not tool specific. Some of the things in the Cisco CCDA will be specific to Cisco, but overall it is a general learning track. Just follow my philosophy in relationship to #1. Focus on the material.
Once you have all of this under your belt look into pulling in pieces of other knowledge. Understanding what is going on is a key to your success. If you understand what goes on with an IP packet, learning tools like Wireshark will be easier. As you progress let things grow organically from this point. Adding equipment in from a Vendor? Update your knowledge or press the new vendor for training options. Branch out into some other areas ,such as security, to add to your overall understanding.
Never stop learning! Visit our online store for links to recommend books and products.
WISP Based Traning Folks.
These companies and individuals provide WISP based training. Some of it is vendor focused. Some are not. My advice is to ask questions. See if they are a fit for what your goals are.
If you provide training let me know and I will add you to this list.
Direct from their web-site.
How to Report
when reporting for a service outage. Once verified we will plot it on tracker.
For e.g. #outage #loc (street, city – location name) #start (time), followed by #back (time)#planned or #unplanned (if its a planned or unexpected outage).
Send comments/feedback/feature requests tovirendra[dot]rode[at]outages.org
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So Mikrotik has a very cheap hAP Lite coming out. This is a 4 port, 2.4 b/g/n router/access point which retails for $21.95. Baltic networks has pre-orders for $18.95.
Why should you deploy this little gem and how? We have found over the years routers account for more than half of the support issues. In some networks this number is closer to 80-90%. Whether it be a substandard router, one with out of date firmware, or poor placement by the customer.
Deployment of the hAP lite can be approached in one of two ways. Both ways accomplish the same goal for the ISP. That goal is to have a device to test from that closely duplicates what the customer would see. Sure you can run tests from most modern wireless CPE, but it’s not the same as running tests m the customer side of the POE.
Many ISPs are offering a managed router service to their customers. Some charge a nominal monthly fee, while others include it in the service. This is a pretty straightforward thing. The customer DMARC becomes the wireless router. The ISP sets it up, does firmware updates, and generally takes care of it should there be issues. The managed router can be an additional revenue stream in addition to providing a better customer experience. Having a solid router that has been professionally setup by the ISP is a huge benefit to both the provider and the customer. We will get into this a little later.
Second option lends itself better to a product such as the hAP lite. With the relative cheap cost you can install one as a “modem” if the customer chooses their own router option. The actual method of setup can vary depending on your network philosophy. You can simply bridge all the ports together and pass the data through like a switch. The only difference is you add a “management ip” to the bridge interface on your network. This way you can reach it. Another popular method, especially if you are running PPPoE or other radius methods, is to make the “modem” the PPPoE client. This removes some of the burden from the wireless CPE onto something a little more powerful. There are definite design considerations and cons for this setup. We will go into those in a future article. But for now let’s just assume the hAP is just a managed switch you can access.
So what are the benefits of adding one of these cheap devices?
-You can run pings and traceroutes from the device. This is helpful if a customer says they can’t reach a certain web-site.
-Capacity is becoming a larger and larger issue in the connected home. iPads, gaming consoles, tvs, and even appliances are all sharing bandwidth. If you are managing the customer router you can see the number of connected devices and do things like Torch to see what they are doing. If a customer calls and says its slow, being able to tell them that little Billy is downloading 4 megs a second on a device called “Billy’s xbox” can help a customer. It could also lead to an upsell.
-Wireless issues are another huge benefit. If the customer bought their own router and stuck it in the basement and now their internet is slow you have a couple of tricks to troubleshoot without a truck roll. If the hAP is in bridge mode simply enable the wireless, setup an SSID for the customer to test with and away you go. This could uncover issues in the house, issues with their router, or it might even point to a problem on your side.
-Physical issues and ID10T errors can be quickly diagnosed. If you can’t reach your device it’s either off or a cabling issue. If you can reach the hAP and the port has errors it could be cabling or POE.
These are just a few benefits you can gleam from sticking a $20 Mikrotik device on your customer side network. It becomes a troubleshooting tool, which makes it money back if it saves you a single truck roll. The implementation is not as important as having a tool closer to the customer. There several vendoars you can order the hAP lite from. Baltic Networks is close to me so they are my go-to. http://www.balticnetworks.com/mikrotik-hap-lite-tc-2-4ghz-indoor-access-point-tower-case-built-in-1-5dbi-antenna.html .
This isn’t practical for business and Enterprise customers, but you should already be deploying a router which has these features anyway right? 🙂
Are you an ISP with some new space and it’s not being geo-located in the correct spot?
Some notable news for the xISP world.
MTIN would like to announce some exciting new services for ISPs and network operators
The first is Midwest Internet Exchange ( www.midwest-ix.com )
MidWest-IX has created a peering fabric we are expanding to data centers focused on the needs of WISPs and network operators such as yourself. Peering can be a valuable, and cost-effective solution for your ISP. MidWest-IX has created a solution based around those needs.
We are tailoring and providing these services to the WISP community as a way of making everyone stronger. WISP operators need advantages. MidWest-IX can provide lower latency to content providers such as Netflix. MidWest-IX can cut down on transit costs through peering. We are also creating an ever-growing marketplace for members to provide redundancy, market goods and services to each other, and create a WISP peering cloud. We have many more benefits of an exchange listed at: http://www.midwest-ix.com/benefits.html
We have exchange services available at:
350 East Cermak Chicago Illinois
733 West Henry Street Indianapolis Indiana
401 North Shadeland, Indianapolis Indiana
900 Walnut St. Louis Missouri
535 Scherers Court Columbus, Ohio
If you are a WISP in Indiana, Ohio, Illinois, Kentucky, Michigan, or Missouri contact us on how we can leverage the exchange to help your business. Other locations planned for 2015.
Our next announcement includes services in several Data Centers.
MTIN in cooperation with Midwest Internet Exchange (M-IX) offers co-Location, bandwidth, peering, transport, and managed services.
Do you have a need for circuit termination, server/router space, or peering in any of the above locations? Let us put together a managed solution for you. MTIN can handle the ins and outs of cross-connects, facilitating ports to the exchange fabric, and other data center needs. A data center can be an intimidating thing. Let us take the guesswork out of it for you.
-Bandwidth (let our experts provide unique and out-of-the-box solutions)
-Cross connects and cable landings
-Off-site backup and DR
-Co-location (TierIV and basic Co-location)
-Connections to 3rd Party networks such as Internet2
MTIN provides xISP consulting and backend solutions. BGP, OSPF, routing, DNS, network engineering, and other services. Talk to us how we can put together a complete solution to optimize your network. Our Engineers can design a cost-efficte solution that fits you and your needs.