Is SPB the Betamax of Layer 2?

Posted on October 2, 2012 by networkingnerd

While I was at Brocade Tech Day, I had the wonderful opportunity to sit down with Jon Hudson (@the_solutioneer) and just talk for about half an hour. While the rest of the day was a whirlwind of presentations and interviews, Jon and I talked about all manner of things not related to VDX or VCS. Instead, we had a very fascinating discussion about TRILL and SPB.

For those not familiar, TRILL is the IETF standard for the issue of layer 2 multipath. It’s a very elegant solution for the spanning tree problem. Our data centers today are running at half capacity. That’s not because we don’t have enough bandwidth, though. It’s because half our links are shut down, waiting for a link failure. Thanks to 802.1d spanning tree, we can’t run two links at the same time unless they are bundled into a link aggregation (LAG) solution. And heaven forbid we want to terminate that LAG bundle on two different switches to prevent single-switch failure from affecting our traffic. Transparent Interconnection of Lots of Links (TRILL) fixes this by creating a layer 2 network with link state. It accomplishes this by running a form of IS-IS, which allows the layer 2 nodes to create an SPF table and determine not only the best path to a node, but other paths that could be equally as good. This means that we have a real fabric of interconnections with no blocked links.

802.1aq Shortest Path Bridging, or SPB informally, is the IEEE version of a layer 2 multipathing replacement for spanning tree. It looks a lot like TRILL and even uses IS-IS for the layer 2 protocol as well. It does differ in some respects, such as using MAC-in-MAC encapsulation for frames as opposed to rewriting the header like TRILL does. This makes it very attractive to the service provider market, as they don’t have to buy a bunch of new gear to get everything up and running quickly on SPB. Looking at the proponents of SPB, such as Avaya and Alcatel-Lucent that really comes as no surprise. Those companies are heavily invested in the service provider space and would really love to see SPB adoption take off as it would protect their initial investments.

The showdown between TRILL and SPB isn’t that far removed from the old showdown between VHS and Betamax. For those not entirely familiar, this was a case of two competing standards that was eventually settled in the court of the consumer. While many regard the early Betamax units as technologically superior, there was an issue of tape length (1 hour vs the VHS 2 hour limit). As time wore on, there was significant development done on both sides that stretched the formats to their absolute limits. However, by the end, VHS had won due to simple popularity. Since VHS had become the most popular format for consumers, even the supposed superiority of Betamax couldn’t save it from being relegated to the junk pile of history. Another more recent case is the battle between HD-DVD and Blu-ray. Similarly to the analog format wars decades earlier, the digital disc war erupted from two alliances thinking they had the best solution to the problem. Blu-ray eventually won out in much the same way that VHS – by becoming the format that most people wanted to use. The irony that Sony actually won a format war isn’t lost on a lot of people either.

I believe that we’re going to see something like these showdowns in TRILL vs. SPB. Right now, the battle lines seem drawn between the data center vendors supporting TRILL and the service provider vendors getting ready to implement SPB. Whether or not one of the solutions is technically superior to the other is inconsequential at this point. It’s all going to come down to popularity. Brocade and Cisco have non-standard TRILL implementations in VCS and FabricPath. The assumption is that they will be compatible with TRILL when a working solution is finally released. I’m also guessing that we’re going to see more support for TRILL in the cloud providers to maximize their revenue potential by offering non-blocking paths to increase throughput for those hungry cloud applications. Brocade showcased some providers moving to VCS at Brocade Tech Day. If that’s the case, we’re going to see TRILL at the enterprise level and the cloud provider level connected by an SP core running SPB. Just like Betamax being the favorite of the professional video industry, SPB will be the go-to protocol for providers, as they can put of yet one more round of equipment upgrades. I think by that point, however, TRILL will have obtained enough critical mass to drive adoption to the point where TRILL silicon will be a very inexpensive option on most new equipment in a few years, perhaps even becoming the default configuration. If that is indeed the case, then TRILL will indeed become the VHS or Blu-ray of this protocol war.

Tom’s Take

I can still remember going into the video store and seeing the great divide. On one side, Betamax. On the other, VHS. Slowly, the Betamax side of the house shrank away to nothing. It happened again with HD DVD and Blu-ray. In the end, both format wars came down to popularity. VHS was in more households and offered the ability to record two hours worth of programming instead of one. Blu-ray got the popular movie studios on board quickly, like Disney. Once the top selling movies were on Blu-ray, the outcome was all but guaranteed. In the big debate of TRILL against SPB, it’s going to come down to popularity. I think we’re already seeing the beginning of TRILL winning this fight. Sure, the service providers are going to use SPB as long as they can to avoid upgrading to TRILL-compatible hardware. I could even make a pretty compelling case the neither of these two layer 2 protocols would make a bunch of sense for a service provider. At the end of the day, though, I’m pretty sure that we’ll eventually be speaking about SPB in the same hushed nostalgia we reserve for the losers of the format wars so many years ago.

Here are a few posts about TRILL and SPB that generated some ideas for me. You should check them out too:

Does TRILL Stand A Chance At Wide Adoption – Ethan Banks

Why SPB Doesn’t Get Any Attention – Greg Ferro

TRILL and 802.1aq (SPB) Are Like Apples and Oranges – Ivan Pepelnjak

NANOG 50 TRILL vs. SPB Great Debate – PDF of a huge discussion presentation

Network Field Day 4

Posted on September 27, 2012 by networkingnerd

I am once again humbled and honored to accept an invitation to my favorite industry event – Network Field Day (now in its fourth iteration). Network Field Day 4 (NFD4) will be coming to you from San Jose October 10-12th. The delegate lineup has a bunch of new faces that I’m excited to catch up with and/or meet for the first time:

	Anthony Burke	@Pandom_
	Bob Plankers	@Plankers
	Brad Casemore	@BradCasemore
	Brent Salisbury	@NetworkStatic
	Colin McNamara	@ColinMcNamara
	Greg Ferro	@EtherealMind
	Michael McNamara	@mfMcNamara
	Paul Stewart	@PacketU

This is a great crew with a lot to say and I’m anxious to see them unleashed on our assembled sponsors:

Brocade – I’m betting that VCS is going to be up on the block this time around. We got a chance to play with it a while back and we had a blast. With the annoucements that you’ve made around Brocade Tech Day, I’d like to hear more about the VCS strategy and how it will dovetail into your other product lines. I’d also like to hear more about the ADX and how you plan on terminating VXLAN tunnels in hardware. Please be sure that you can talk about these in decent depth. Being told over and over again that something is NDA when it shouldn’t be a huge mystery is a bit disconcerting. Also, if Jon Hudson isn’t presenting, at least have him show up for a few minutes to say hello. We love that guy.During Wireless Field Day 3, Gregor Vučajnk (@GregorVucajnk) had a great blog post about attending that had something that I’m going to borrow for this NFD outing. He called out each of the participating sponsors and gave them a short overview of what he wanted to see from each of them. I loved the idea, as it gives a bit more direction to the people making the decisions about presentation content.

Cisco Borderless – Please, please, oh please tell me what Borderless really means. Even if it’s just “everything but data center and collaboration”. I really want to know how you’re pulling all these product lines together to create synergy. Otherwise, it’s still just going to be the routing BU, switching BU, and so on. We had a great time listening to the last presentation about ASA CX and Wireshark on the Cat 4500. More of that good stuff, even if it means you have to shave your presentation down a bit to accommodate. Remember, we ask lots of questions.

Juniper – Firstly, I want a bit of talk about Ivan’s post exploring all the gooey details around QFabric. I understand that in this case it may be a bit like the magician telling how the trick is done, but this is the kind of thing that fascinates me. I’m also sure there’s going to be discussion around SDN and the Juniper approach to it. The presentation at NFD2 was so great I want to see you keeping up the good work.

OpenGear – Hello there. I know nothing about you beyond the cursory Google search. It looks like you’ve got some interesting technology that could be of great use to network professionals. Case studies and anecdotes about using a 3G console failover to prevent global chaos would be awesome. Also, allowing us the opportunity to poke around on a box for a few minutes would rock. I want to think about how I can use your product to make my life less miserable when it comes to offline console access.

Spirent – Hello again to you. I didn’t know anything about Spirent last time, but now I see them everywhere I look. Spirent is like the Good Housekeeping seal for network gear. Lets dive deeper into things. I know you’re squeamish about showing off GUIs and things like that, but we nerd out on those things. Also, I want to talk about how you plan on building testing rigs to handle all the coming 100GigE traffic. Show me how Spirent is going to keep up the Ginger Rogers mystique that I’ve associated with it.

Statseeker – Network Performance Management and monitoring can be a bit of a dry subject, but doing it with an accent from the Land Down Under could be a bit of a treat. After your recent Packet Pushers episode, I want to drill down more into how you go about keeping all the monitoring data. I’ve seen what overwhelming an NMS with data can do, and while it was a pretty light show, I want to prevent it from happening again. I don’t expect you to bring one of your famous Minis to give away to the delegates, but don’t underestimate the power of bribery via Tim Tam.

Tech Field Day – Audience Participation

For those of you that like to follow along with the Tech Field Day delegates from the comfort of your office chair or recliner, you are more than welcome. I’ve even seen people talking about taking the day off from work or making sure they aren’t on a remote site. We will be streaming each of the presentations live at http://techfieldday.com. Note that this stream does use uStream, so we aren’t optimized for mobile devices just yet. We’re working on it, though. We will also be spending a lot of time on Twitter discussing the presentations and questions about them. Just make sure to use the hashtag #NFD4 and you can be a part of the discussion. I love seeing discussion and commentary from all the people watching online. I always make sure to keep my Twitter client at the forefront so I can ask questions from the home audience when they arise. That way, I’m truly a delegate representing people and giving them a say in what shapes the events.

If you’d like to learn a little more about Tech Field Day, you can head over to http://techfieldday.com and read up on things. You can also apply to be a delegate at this link. I look forward to seeing you online and hearing from you at this Tech Field Day event.

Standard Tech Field Day Sponsor Disclaimer

Tech Field Day is a massive undertaking that involves the coordination of many moving parts. It’s not unlike trying to herd cats with a helicopter. One of the most important pieces is the sponsors. Each of the presenting companies is responsible for paying a portion of the travel and lodging costs for the delegates. This means they have some skin in the game. What this does NOT mean is that they get to have a say in what we do. No Tech Field Day delegate is every forced to write about the event due to sponsor demands. If a delegate chooses to write about anything they see at Tech Field Day, there are no restrictions about what can be said. Sometimes this does lead to negative discussion. That is entirely up to the delegate. Independence means no restrictions. At times, some Tech Field Day sponsors have provided no-cost evaluation equipment to the delegates. This is provided solely at the discretion of the sponsor and is never a requirement. This evaluation equipment is also not a contingency of writing a review, be it positive or negative.

Reality As A Service

Posted on September 24, 2012 by networkingnerd

If you are a fan of Tech Field Day or a frequent viewer of my blog posts, you know that I’m somewhat skeptical of the majority of analyst firms out there. At best, many of them function solely as a mouthpiece regurgitating old information to remind CxOs that the decisions they made 2-3 years ago were the right ones. At worst, they are the paid shills for companies looking for market share and attention. Thanks to a convenient vendor event, I got to spend some time picking the brains of many of my colleagues about topics like this, and I find I’m not alone. Independence and objectivity are always important, and as I’ve said in the past when talking about an independent testing company idea, it can be hard to maintain in an environment where you are so reliant on the vendors to provide support and funding for the things you want to do. After all, not everyone can be as rich as Richard Branson. I think, however, that I might have finally hit on an idea that could work for me.

The movie Patton holds a clue to my devious intentions. Within, the general describes a scene from ancient Rome. Conquering generals were awarded a triumph, a giant parade through the heart of Rome where the population would shower the hero with adulation and praise. For those very successful generals, this could soon become a source of feelings of superiority. After all, here are all these people telling you how great you are. Sooner or later, you’re going to start believing your own press. According to Patton, however, it was common practice for a slave to stand behind the general and whisper in his ear every so often, “Remember, fame is fleeting…” This is the “what have you done for me lately” mentality so prevalent today. People quick to forget your successes but take a very long time to forgive your failures. No where is this more apparent to me that in the audition process for the TV show American Idol. For the five of you that might not be familiar with this particular program, it’s essentially a serialized talent competition/reality show. The real interesting part for most people isn’t the competition itself. It’s the auditions for the first two to three weeks of each season. This is where you get to see the people that turn up and try out. Many of these people have absolutely no business singing. At all. For whatever reason, whether it be believing their own press or the false praise of others, these people truly think they have amazing talent where none actually exists. These “trainwrecks” drive a lot of the views for the first few episodes because people take some kind of perverse delight in watching failure. Once the trainwrecks are finished, the real competition can start.

I’ve always said to myself that what these trainwrecks need is a harsh dose of reality. I’ve been gifted in my life that I’ve been able to have people tell me that maybe I wasn’t best suited to be a singer or a baseball player. They encouraged me to work toward realistic goals, like being a snarky network rock star. However, some of these American Idol contestants don’t have that. They go right on believing they can sing like a real rock star until they get in front of the cameras and Simon Cowell hammers them with reality in front of the whole nation. What I had originally proposed was a service that did much the same thing, only not so public. For those people that care enough to tell these contestants that maybe singing isn’t what they were cut out for but can’t bring themselves to do it for whatever reason, I would gladly offer my services in their stead. I can call people up and let them know that the prevailing opinion is that while they might sound good in the shower, they really shouldn’t try to make a living singing old show tunes in front of a harsh judging panel.

My conversations as of late have finally made the lightbulb go off and join these two disparate ideas together. That’s what bothers me to a degree about the analyst firms. They never really have anything bad to say. The praise is heaped on by the ladle full in many cases. Everyone has a positive place in the mystical polygon. There is no “suck” quadrant. Yet, when we expose these technologies to real deployments and real workloads, they start breaking and causing all manner of problems. What we really need is a Reality As A Service offering. Myself, along with a group of talented individuals, will pour over your product offering and tear it to shreds. These reports are going to be decidedly negative. We’re going to tell you all the things that are wrong with your widget. Just like the slave in the chariot in Rome, we’re going to remind the vendors that all the praise being offered by the crowd is fleeting. Instead, in three months time the only thing people will care about is how broken your product is. By contracting with Reality As A Service, we will tell you up front all the things you don’t want to hear and the regular analysts don’t want to tell you. You may not want to hear it. You may not like us very much after we’re finished. But, you won’t be able to tell us we’re absolutely wrong. And you will then have a list of things to work on to make your product better.

It’s not unlike submitting an article or a book to an editor for proofreading. It think I have a fairly decent grasp of the English language. However, watching a professional editor slice-and-dice my work reminds me how far I still have to go. I don’t hate the editor for pointing out my mistakes. I make myself better by recognizing those problems and correcting them. That’s what Reality As A Service can help fix. Bad GUI interfaces, horrible design decisions, and academic delusion with the way things operate outside of an incubation vacuum. Does your interface still rely on Java or Flash? We’ll tell you. How about requiring a $50,000 license for a feature that should really be free at this point? We’re going to bring that up too. And why on earth doesn’t this use the same standard protocol that the rest of the world has used for the last five years?!? That’ll be in the report as well. In the end, rather than hear how great you are, you’ll be reminded of all the things you should be concentrating on. Reality As A Service won’t let you lose sight of all the important things because others are too busy telling you how great the unimportant things are.

Does this idea have a future? Not likely. People that create things don’t take kindly to being told their widgets aren’t up to snuff. Just like the American Idol contestants that come out of the audition after being smacked in the face with reality and say, “I don’t know what the professional talent judge was thinking. My mom tells me that I’m the best singer she’s heard in the general store in the last fifty years!” They can’t accept criticism when they are absolutely convinced they are right. But for a small portion of the people, the ones that can accept constructive feedback and use it as a tool to better themselves and the products they make, there might just be some hope.

Brocade Tech Day – Data Centers Made Simple

Posted on September 19, 2012 by networkingnerd

When I was just a wee lad, my mom decided one year that she’d had enough of the mass produced Halloween costumes available at the local department store. I wanted to be a ninja (surprise, I know) and she was determined to make me the best ninja costume around. My mother knows how to sew, but she isn’t a seamstress by any stretch of the imagination. What she did do was go to the fabric store and pick up a package of Simplicity patterns. These are wonderful. They enable those of us without the gift of textile assembly to create something from fabric that can be astounding. Simplicity takes all the guesswork out of making a costume by giving you easy-to-follow directions. You don’t have to think about the process beyond a few cuts and some stitches. Instead, you can think about the applications of the final product, from ninja to Jedi to superhero.

You may be asking yourself…what does this have to do with Brocade and networking? At Brocade Tech Day, myself and other analysts sat down to hear about the new story from Brocade in the data center. At the heart of the message was the work “simplicity”. Simplicity Through Innovation. The need to radically simplify things in order to achieve the scale and efficiency we need to create huge data centers. And at the center of it all is Brocade’s VCS Ethernet fabric. I got a chance to kick the tires on VCS back at Network Field Day 2, but the announcements at Brocade Tech Day were a bit more ambitious. That’s because the face of VCS is now the Brocade VDX 8770. This switch is a monster. It has the capability of learning up to 384,000 MAC addresses in those little CAM tables. It has the capacity for 384 10GigE and 96 40GigE ports, as well as expandability to 100GigE. Though I’m a bit unsure of how they arrived at the numbers, they claim it can support up to 320,000 virtual machines on those ports. Ivan Pepelnjak did a great breakdown of the capabilities of the switch on launch day. I’m especially keen on the idea that you can create a four-way virtual gateway that shares the same IP and MAC address. This overcomes the limitations of HSRP/VRRP, as well as some of the quirkiness of GLBP. That shows that Brocade is at least thinking beyond layer 2, unlike a lot of data center vendors that believe the world is flat (networking wise). After speaking with Lisa Caywood (@TheRealLisaC), I found that this huge iron switch is being used by customers not at the core of the network but instead at the edge of the data center, where all those hungry hypervisors and servers live. All the numbers that I’m seeing from the VDX 8770 point to it as a way to aggregate a huge amount of packets coming from a data center server farm and feed it through the rest of the network via VCS. That makes total sense when coupled with some of Brocade’s prognostications, such as 80% of server traffic becoming east-west (server-to-server) in the next year or so.

Brocade also had some other interesting pieces on display. One of them was a new capability for the ADX application delivery controller, or load balancer as 90% of the rest of the world calls it. The ADX is slated to begin using Field Programmable Gate Arrays (FPGAs) to terminate VXLAN tunnels before they head into the VCS fabric. I find it very interesting that they chose FPGAs to do this, having seen something similar from Arista just a few months ago. I also get to chuckle a little bit to myself when one of the cornerstones of the software defined networking (SDN) world is terminated in a hardware construct. I suppose it brings a bit of order back to my world. Another interesting thing that came up during the presentations is that Brocade is making all their own silicon in the VDX 8770 and moving forward. In a day and age where moving to merchant silicon seems to be the flavor of the month, I’m curious as to where Brocade is headed with this. Obviously, the ability to create your own chips gives you an advantage over other competitors when it comes to designing the chip the way you want it to function, such as putting 38MB of TCAM on it or producing something with a ridiculously low port-to-port latency. However, the agility afforded from merchant silicon gives other vendors the ability to innovate in the software arena. That, I believe, is where the battleground is really going to be in the coming months. On the one side, you’ll have vendors invested in custom silicon that will be doing amazing things with hardware. On the other side, you’ll have the merchant silicon vendors that are all using very similar reference designs but are really concentrating on innovation in software. It’s an exciting time to be in networking for sure.

Brocade Tech Day Disclaimer

I was invited to attend Brocade Tech Day by Brocade. They paid for my airfare and lodging. I also attended an executive dinner that evening that was provided by Brocade. At no time during this process was any requirement made of me in regards to posting information about Brocade Tech Day. Brocade did not ask for nor were they promised any consideration in this post. The conclusions and analysis herein are mine and mine alone.

Death to 2.4GHz!

Posted on September 14, 2012 by networkingnerd

This week was the annual announcement of the Apple iPhone refresh. There were a lot of interesting technologies discussed around the newest entry in the Cupertino Fruit and Mobile Company but one of the most exciting came in the form of the wireless chip. The original iPhone and the iPhone 3G were 802.11b/g devices only. Starting with the iPhone 3GS, Apple upgraded that chip to 802.11b/g/n. With the announcement of the new iPhone 5, Apple has finally provided an 802.11a/n radio as well, matching the 5GHz capability as the iPad. This means that all Apple devices can now support 5GHz wireless access points. Along with the latest Android devices that offer similar support, I think the time has come to make a radical, yet needed, design decision in our wireless networks.

It’s time to abandon 2.4GHz and concentrate on 5GHz.

Matthew Gast from Aerohive had a great blog post along these same lines. As Matthew explains, the 2.4GHz spectrum is awash with interference sources from every angle. Microwave ovens, cordless telephones, and wireless video cameras are only part of the problem. There are only three non-overlapping channels in 2.4GHz. That means you’ve got a 33% chance of interfering with surrounding devices. If you’ve got one of those fancy consumer devices that can do channel aggregation at 2.4GHz, the available channels decrease even further. Add in the fact that most people are carrying devices now that are capable of acting as access point, such as MiFi hotspots or the built-in hotspot features in tablets and smartphones and you can see how the 2.4GHz spectrum is a crowded place indeed. On the other hand, 5GHz has twenty three non-overlapping channels available. That’s more than enough to satisfy the more dense AP deployments required to provide similar coverage patterns while at the same time providing for high speed throughput with channel aggregation.

There are a number of devices that are 2.4GHz only and will continue to be that way. Low-power devices are one of the biggest categories, as Matthew pointed out. 2.4GHz radios just draw less power. Older legacy devices are also not going to be upgraded anytime soon. That means that we can’t just go around shutting off our 2.4GHz SSIDs and leaving all those devices out in the cold. What it does mean is that we need to start focusing on the future of wireless. I’m going to treat my 2.4GHz SSIDs just like a guest access VLAN. It’s there, but it’s not going to get much support. I’m going to enable band steering to push the 5GHz-capable clients to the better access method. For everyone else that can only get on at 2.4GHz, you get what you get. With more room to grow, I can enable wide channels and let my clients pull all the data they can stand from 5GHz. When the rest of the world gets ready to deploy 802.11ac devices and APs, I’ll already have experience designing for that band. My 2.4GHz network will live on much the same way my 802.11b clients lived on and my Novell clients persisted. They’ll keep churning until they are forced to move, either by failure or total obsolescence.

Tom’s Take

Yes, it’s a hard choice to make right this moment to say that I’m leaving 2.4GHz to the wolves and moving to 5GHz. It’s a lot like making the decision between ripping the band-aid off or pulling it slowly. Either way, there will be pain. The question becomes whether you want the pain all up front or spread out over time. By making a conscious decision to start focusing your efforts of 5GHz, you get the pain out of the way. Fighting for spectrum and positioning around kitchens and water pipes all fall away. Coverage takes care of itself. Neat new technology like 40MHz channels is simple, relatively speaking. Let the 2.4GHz clients have their network. I’m going to concentrate my efforts on where we’re headed, not where we’ve been.

Do They Give Out Numbers For The CCIE Written?

Posted on September 11, 2012 by networkingnerd

I’ve seen a bit of lively discussion recently about a topic that has vexed many an engineer for years. It revolves around a select few that put “CCIE Written” as their title on their resume or their LinkedIn account. While they have gone to great lengths to study and take the 100-question multiple choice written qualification exam for the CCIE lab, there is some notion that this test in and of itself grants a title of some sort. While I have yet to interview someone that has this title, others that I talk to said they have. I have been in a situation where some of my co-workers wanted to use that particular designation for me during the period of time when I passed the written but hadn’t yet made it through the lab. I flat out told them “no.”

I understand the the CCIE is a huge undertaking. Even the written qualification exam is a huge commitment of time and energy. The test exists because the CCIE has no formal prerequisite. Back before the CCNA or the CCNP, anyone could go out and attempt the CCIE. However, since lab spots are a finite resource, some method of pre qualification had to be in place to ensure that people wouldn’t just book spot after spot in the hope of passing the lab. The written serves as a barrier to entry that prevents just anyone from grabbing the nearest credit card and booking a lab slot they may have no hope of passing. The written exam is just that, though – a qualification exam. It doesn’t confer a number or a title of any kind. It’s not the end of the journey. It’s the beginning. I think the rise of the number of people trying to use the CCIE written as a certification level comes from the fact that the exam can now be used to recertify any of a number of lower level certifications, including CCxA, CCxP, and almost all the Cisco Qualified Specialist designations. That’s the reason I passed my first CCIE written. At first, I had no real desire to try and get my brains hammered in by the infamous lab. I merely wanted to keep my professional level certifications and my specialist tags without needing to go out and take all those exams over again. However, once I passed the written and saw that I indeed knew more about routing and switching than I anticipated, I started analyzing the possibility of passing the lab. I passed the written twice more before I got my number, both to keep my eligibility for the lab and to keep my other certifications from expiring. Yet, every time someone asked me what my new title was after passing that test I reminded them that it meant nothing more beyond giving me the chance at a lab date.

I’m not mad at people that put “CCIE Written” as their title on a resume. It’s not anger that makes me question their decision. It’s disappointment. I almost feel sorry that people see this as just another milestone that should provide some reward. The reward of the CCIE Written is proving you know enough to go to San Jose or Brussels and not get your teeth kicked in. It doesn’t confer a number or a title or anything other than a date taken and a score that you’ll need to log into the CCIE site every time you want to access your data (yes, even after you pass you still need it). Rather than resting your laurels after you get through it, look at it as a license to accelerate your studies. When someone asks you what your new title is, tell them your lab date. It shows commitment and foresight. Simply telling someone that you’re a CCIE written is most likely going to draw a stare of disdain followed by a very pointed discussion about the difference between a multiple choice exam and a practical lab. Worst case scenario? The person interviewing you has a CCIE and just dismisses you on the spot. Don’t take that chance. The only time the letters “CCIE” should be on your resume is if they are followed by a number.

A Talk in the Park – Using Call Park and Directed Call Park

Posted on September 7, 2012 by networkingnerd

Anyone that has ever used a phone is familiar with being placed on hold. Most of the time, you get to hear nice, soothing music while the person on the other end of the line tries to figure out something without either shouting into the phone or having a long period of uncomfortable silence. The hold button is usually the most worn-out button on the key systems that I replace. However, on the newer PBXs that I install, the hold button is quickly losing its usefulness. Hold work well when every line on your phone system is on every phone, like it is in a key system. Placing Line 1 on hold at the reception desk phone allows Line 1 to be picked up by the CEO at their phone. However, what happens in a PBX environment when the incoming lines don’t appear on every phone? The hold button will still place the caller on hold, but only on the phone where the call was initially held. In order to move that caller to another phone, you’ll need to transfer the caller or have the CEO come up to the reception desk. These may not be the most effective solutions for most people. What if there was another way?

My first experience with a “modern” PBX was with the call park feature. Rather than relying on the hold button and tying up the lines coming into the building, the park button takes a different approach. When a caller wants to speak to someone other than the person that they called, the receiver of the call can “park” the caller. Parking a call is like placing the call on hold, but on a phantom extension that can be accessed system-wide. Now, rather than having the CEO go to the reception desk to retrieve the call, the CEO can dial an extension and retrieve the parked call whenever it’s convenient. Call park is a great solution for places where not everyone has a phone or usually isn’t near their extension. Think of a warehouse or a retail sales floor. These users may not have ready access to a phone to take a call. It’s better for them to find an extension and take the call when possible. That’s where the genius of call park comes into play. Without a doubt, call park is the number one feature on my office phone system. If it stopped working for some reason, there might just be a riot. For users that don’t use it already, telling them about the feature when I’m doing the installation is like a ray of sunshine for them.

Configuring Call Park

I’m going to show you how to configure Call Park on Cisco equipment, seeing as that’s the one that I work on most of the time. Your mileage may vary on your flavor of system. If you’re using Cisco Unified Call Manager:

1. After logging into the system, head to Call Routing -> Call Park.

2. You’ll see a screen that looks like this:

The Call Park Number/Range field can accept either a single park number or a range (using the same X wildcard as a route pattern). I’d recommend a range to give yourself some flexibility. Be aware, though, that the limit for a single range of park slots is 100. If you need more than that, you’ll need to create a different pattern. I usually set aside 10 or so. The description field is pretty self-evident. The partition should be one that’s dialable from the phones that you want to access the park feature. I usually just put it in my cluster resources or internal DNs partition. The CUCM field gives you a bit of control over which cluster you assign the park slots.

3. Once you’ve created the park slots, be sure to check the Phone Button Template that the phones are using to ensure there is a Park softkey available for use by the users. I tend to move the key to the first row of softkeys to ensure that it gets used instead of the hold button. Just be aware that changing the softkey template will require you to restart the phones to make the settings take effect. When your users press the Park softkey, the system will pick the first open park slot ascending in the park pattern created and leave the call there. The screen will display the park slot that is holding the call for about ten seconds. You can tweak this timer under System -> Service Parameters -> Cisco CallManager

If you find yourself on a CUCME system, configuring a park slot is as easy as this:

ephone-dn  40 
 number 601 secondary 600 
 park-slot timeout 60 limit 10 
 no huntstop 
! 
! 
ephone-dn  41 
 number 602 secondary 600 
 park-slot timeout 60 limit 10 
 no huntstop 
! 
! 
ephone-dn  42 
 number 603 secondary 600 
 park-slot timeout 60 limit 10 
 no huntstop 
! 
! 
ephone-dn  43 
 number 604 secondary 600 
 park-slot timeout 60 limit 10 
 no huntstop

This will setup four park slots with their own number and a shortcut. One other quick note here. If you accidentally configure an ephone-dn as a park slot and later need to use it for a phone DN, you’re going to need to remove the whole DN and add it back in with the right configuration. For whatever reason, marking a DN as a park slot is one-way job until it’s been deleted.

Directed Call Park

As much as I love call park, it does have one downside. Once a call has been parked in a call park slot, there’s no real way to monitor it. The call park slot is basically a phantom extension with no way to watch what’s going on. While that may be fine for a small office with five or six slots, what happens when an enterprise with thirty slots needs a little more control? What if you want to ensure that you always park an executive’s calls on the same slot? You can’t do that with a regular call park slot. That’s where directed call park comes into play. Directed Call Park allows you to designate a range of park extensions that can be monitored via Busy Lamp Field (BLF) buttons. You can also use those same BLF buttons as a speed dial to rapidly park calls in the same slots every time. This makes a lot more sense for a large enterprise switchboard. The configuration is very similar, with only a couple of extra fields:

Most of it looks the same. The new fields include the reversion number and CSS. This is where the call will be sent if no one picks it up in a certain period of time. Normal call park sends the call back to the extension that parked it. With directed call park, you will usually want the call to go to a central switchboard or receptionist. If you leave these optional fields blank, it will behave just like the normal call park slot. You’ll also notice that the Retrieval Prefix is a required field. Directed Call Park requires you to prefix the park slot with a code for access. If you don’t include the prefix, the system does nothing, as it thinks you’re trying to park a non-existant call in an occupied park slot. If your call is parked on 601 and the retrieval prefix is 55, you will need to dial 55601 to pick up the call. When you want to park a call in a directed call park slot, you need to do a consultative transfer to that slot. In the above case, transfer the call to 601, then hit transfer again to send the caller to the park slot. The Park softkey doesn’t do anything here for directed call park and in fact will send the caller to a regular park slot if they are configured.

Tom’s Take

Call park is a make-or-break feature for me. I always talk about it in the phone system training that I give to people when first setting up their systems. I caution them against using hold any longer. The only time I use hold on my own phone is when I’m looking something up or I need to step away from the phone for a few seconds. I treat the hold button like a mute button with music. Call park is the new hold. Call park gives you everything that the hold button ever could and more. You can move calls where you need them to be without worrying about which phone has the call. When you add in directed call park to give your switchboard the flexibility to monitor calls and control where calls are parked people will being to wonder how they ever lived without it. You may even find that you can remove the Hold softkey from your phone button templates. And then your job really will be a walk in the park.

SDN and the IT Toolbox

Posted on September 4, 2012 by networkingnerd

There’s been a *lot* of talk about software-defined networking (SDN) being the next great thing to change networking. Article after article has been coming out recently talking about how things like the VMware acquistion of Nicira is going to put network engineers out of work. To anyone that’s been around networking for a while, this isn’t much different than the talk that’s been coming out about any one of a number of different technologies over the last decade.

I’m an IT nerd. I can work on a computer with my eyes closed. However, not everything in my house is a computer. Sometimes I have work on other things, like hanging mini-blinds or fixing a closet door. For those cases, I have to rely on my toobox. I’ve been building it up over the years to include all the things one might need to do odd jobs around the house. I have a hammer and a big set of screwdrivers. I have sockets and wrenches. I have drills and tape measures. The funny thing about these tools is the “new tool mentality”. Every time I get a new tool, I think of all the new things that I can do with it. When I first got my power drill, I was drilling holes in everything. I hung blinds with ease. I moved door knobs. I looked for anything and everything I could find to use my drill for. The problem with that mentality is that after a while, you find that your new tool can’t be used for every little job. I can’t drive a nail with a drill. I can’t measure a board with a drill. In fact, besides drilling holes and driving screws, drills aren’t good for a whole lot of work. With experience, you learn that a drill is a great tool for a range of uses.

This same type of “new tool mentality” is pervasive in IT as well. Once we develop a new tool for a purpose, we tend to use that tool to solve almost every problem. In my time in IT, I have seen protocols being used to solve every imaginable problem. Remember ATM? How about LANE? If we can make everything ATM, we can solve every problem. How about QoS? I was told at the beginning of my networking career that QoS is the answer to every problem. You just have to know how to ask the right question. Even MPLS has fallen into the category at one point in the past. MPLS-ing the entire world just makes it run better, right? Much like my drill analogy above, once the “newness” wore off of these protocols and solutions, we found out that they are really well suited for a much more narrow purpose. MPLS and QoS tend to be used for the things that they are very good at doing and maybe for a few corner cases outside of that focus. That’s why we still need to rely on many other protocols and technologies to have a complete toolbox.

SDN has had the “new tool mentality” for the past few months. There’s no denying at this point that it’s a disruptive technology and ripe to change the way that people like me looking at networking. However, to say that it will eventually become the de facto standard for everything out there and the only way to accomplish networking in the next three years may be stretching things just a bit. I’m pretty sure that SDN is going to have a big impact on my work as an integrator. I know that many of the higher education institutions that I talk to regularly are not only looking at it, but in the case of things like Internet2, they’re required to have support for SDN (the OpenFlow flavor) in order to continue forward with high speed connections. I’ve purposely avoided launching myself into the SDN fray for the time being because I want to be sure I know what I’m talking about. There’s quite a few people out there talking about SDN. Some know what they’re talking about. Others see it as a way to jump into the discussion with a loud voice just to be heard. The latter are usually the ones talking about SDN as a destuctive force that will cause us all to be flipping burgers in two years. Rather than giving credence to their outlook on things, I would say to wait a bit. The new shinyness of SDN will eventually give way to a more realistic way of looking at its application in the networking world. Then, it will be the best tool for the jobs that it’s suited for. Of course, by then we’ll have some other new tool to proclaim as the end-all, be-all of networking, but that’s just the way things are.

No Bridge Too Far – A Quick Wireless Bridge Configuration

Posted on August 31, 2012 by networkingnerd

I constantly find myself configuring wireless bridges between sites. It’s a cheaper alternative to using a fiber or copper connection, even if it is a bit problematic at times. However, I never seem to have the right configuration, either because it was barely working in the first place or I delete it from my email before saving it. Now, thanks to the magic of my blog, I’m putting this here as much for my edification as everyone else’s. Feel free to use it if you’d like.

dot11 ssid BRIDGE-NATIVE
 vlan1
 authentication open
 authentication key-management wpa
 wpa-psk ascii 0 security
!
dot11 ssid BRIDGE44
 vlan 44
 authentication open
 authentication key-management wpa
 wpa-psk ascii 0 security
 !
 interface Dot11Radio0
 encryption vlan 1 mode ciphers tkip
 encryption vlan 44 mode ciphers tkip
 ssid BRIDGE-NATIVE
 !
 interface Dot11Radio0.1
 encapsulation dot1Q 1 native
 no ip route-cache
 bridge-group 1
 bridge-group 1 spanning-disabled
 !
 interface Dot11Radio0.44
 encapsulation dot1Q 44
 no ip route-cache
 bridge-group 44
 bridge-group 44 spanning-disabled
 !
 interface FastEthernet0.1
 encapsulation dot1Q 1 native
 no ip route-cache
 bridge-group 1
 bridge-group 1 spanning-disabled
 !
 interface FastEthernet0.44
 encapsulation dot1Q 44
 no ip route-cache
 bridge-group 44
 bridge-group 44 spanning-disabled

This allows you to pass traffic on multiple VLANs in case you want to put a phone or other device on the other side of the link. Just make sure to turn the switch port connected to the bridge into a trunk so all the information will pass correctly. As always, if you see an issue with my configuration or you have a cleaner, better way of doing things, don’t hesitate to leave a comment. I’m always open to a better way of getting things done.

The Knights Who Say “Um…”

Posted on August 27, 2012 by networkingnerd

The other day, Ethan Banks (@ecbanks) tweeted a rather amusing thought while editing an episode of the Packet Pushers:

https://twitter.com/ecbanks/status/229235835449516032

It’s rather easy to sympathize with Ethan on this. I find myself very conscious of saying “um” when I’m speaking. We’re all guilty of it. “Um” is a buffering word, a form of speech disfluency. People use it as a filler while buying time to think of a more complete thought. Most modern languages have some form of it, whether it be “err” or “ehhh”. Most public speakers have gone to great lengths to analyze their speaking methods to eliminate these pause words. The results, however, seem to point to substitution instead of reconfiguration.

Listen to any presentation involving technical content and you are likely to hear the word “so” more frequently than you’d like. I’m as bad as anyone. Since that presentation, I’ve gone to great lengths to eliminate “so” from my speaking vocabulary as a pause word. Sometimes, I do a pretty good job. Other times, I don’t do as great of a job. There are a few people that work in my office that are constantly looking for my uses of “so” and pointing them out when they happen. It seems that no matter how hard I try, rather than eliminating pause words, I just replace them. Even in my second presentation, I used “hallmark” a lot more than I should. Even with a lot of rehearsal, going off the cuff on some things tends to introduce the moments of indecision and thought processes that end in “um”s and “err”s.

I would much prefer that non-verbal cues be given instead of these pause words. Rather than filling the conversation with unnecessary words, you should use silence as a time to reflect and collect your thoughts. Provided you aren’t speaking over the phone or via a VoIP conversation, silence shouldn’t be regarded as a negative thing. By taking a little extra time to analyze your thoughts before you start speaking, you negate the need to fill dead speaking space with unneeded syllables. An old saying goes, “A pipe gives the wise man time to reflect and the unwise man something to put in his mouth.” You should treat silence just like the pipe. Rather than spending time filling the conversation, really think about what you want to say before you say it. There’s no shame in taking an extra second or two before saying something really insightful or interesting.

I like to record my presentations because it gives me a chance to analyze them at length afterward to see what I was doing wrong. I don’t listen for content the second or third or fourth time. Instead, I try to pick out all the verbal garbage and make mental notes to myself to remove it for the next time. After my IPv6 presentation, I did my best to eliminate “so” from my presenting vocabulary. Now that I’m conscious of saying it, I can concentrate more on avoiding it. The same goes for other pause words and comfort sayings, like “basically” or “interestingly”. Only by repeated viewings of my prior work can I see what needs to be improved. I would encourage those out there reading this to do the same. Have a friend record your presentation or do it yourself with a simple tripod setup. When you’re finished, take the time to analyze yourself. Be honest. Don’t give yourself any quarter when it comes to your speaking strategy. It may be hard to watch yourself on film the first few time you do it, but after a while you begin to realize all the good that it can do for you. You also learn to start tuning out the sound of your own voice, but that’s a different matter entirely.

Tom’s Take

There’s nothing wrong with speech disfluency. In moderation, that is. Words like “um” and “err” should be treated like salt – some is good, but too much ruins the dish. Instead, focus on being conscious of the pause words and eliminating them from your speaking habits. Instead, use silence as the best way to fill the void. You’ll look smarter spending your time thinking about questions and not worrying about what words to fill into the conversation.

The Networking Nerd

Networking With A Side of Snark

Is SPB the Betamax of Layer 2?

Network Field Day 4

Reality As A Service

Brocade Tech Day – Data Centers Made Simple

Death to 2.4GHz!

Do They Give Out Numbers For The CCIE Written?

A Talk in the Park – Using Call Park and Directed Call Park

SDN and the IT Toolbox

No Bridge Too Far – A Quick Wireless Bridge Configuration

The Knights Who Say “Um…”

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