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B U I L D I N G T H E I N F R A S T R U C T U R E T O E N A B L E T H E C H A N G I N G F A C E O F I T

LET THE 40 GIGABIT ETHERNET MIGRATION BEGINEarly adopters of 40 GbE share successes … and pitfalls PLUS:

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A FEW YEARS ago, a group of network engineers laughed in my face when I brought up an article I was writ-ing about 10 GbE migration. All of them were still using 1 GbE, and only a few were even testing 10 GbE switches. The transition, they said, would be long and slow. It was the classic gap between a user’s reality and a journalist’s research.

So it may seem even stranger this month that we have produced an entire issue of Network Evolution about 40 and 100 GbE migration (we even have a piece pondering the future of 400 and Terabit GbE). After all, we are only at the very beginning of widespread 10 GbE implementation.

But things are different now than they were a few years ago. The need for capacity and speed is explod-ing as network teams build private and hybrid clouds and deliver video throughout their campuses and branch offices. So even if they don’t need 40 GbE today, they’ll need to build networks that can be transi-tioned in the future. And that won’t be easy, as Shamus McGillicuddy reports in his feature “40 Gigabit Ethernet: The migration begins.”

The transition will mean testing

new equipment as vendors race to release 40 and 100 GbE-ready switching. It will also require consid-eration of new cabling and optics.

But the challenges don’t stop there. Existing monitoring, trouble-shooting and management tools aren’t ready to scale to new ultra-fast Ethernet networks, reports contributor Jim Frey in his feature “The 100 Gigabit Ethernet manage-ment challenge.” The same problem exists in scaling firewalls and intru-sion detection devices for 40 GbE networks. While vendors are work-ing to upgrade monitoring and secu-rity appliances, engineers testing or newly implementing 40 GbE find themselves patching the problem by load balancing traffic across mul-tiple 10 GbE-ready monitoring and security devices.

The purpose of this issue isn’t to urge readers to invest in 40 and 100 GbE. Instead, it’s to be sure that you are aware of the challenges that lie ahead so that when you invest in your current 10 GbE infrastructure, you do so with future migration to 40 and 100 GbE in mind. n

Rivka Gewirtz LittleExecutive Editor

It’s Not Too Early To Worry About 40 and 100 GbE Migration

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COVER STORY

THE NEED FOR more speed and capac-ity never goes away. Most enter-prises are still rolling out 10 Gigabit Ethernet links in their networks, but already network architects and engineers are preparing for the future because data traffic never stops growing. Early adopters are testing and deploying the first generation of 40 Gigabit Ethernet (GbE) switches and routers to get a step ahead of this continuous onslaught of traffic.

“We are seeing incidental peaks of traffic nearing 10 Gbps,” said Jeroen van Ingen, a network engi-neer at the University of Twente in the Dutch city of Enschede. “Given the traffic growth over the years, we expect to need more capacity within 12 to 24 months. That’s why we decided that new core equipment should support 40 GbE.”

University of Twente’s van Ingen is not alone in predicting the need

for 40 GbE and beyond. Research from the Dell’Oro Group forecasts the overall Layer 2 and Layer 3 Eth-ernet switch market will reach $25 billion in 2016, with 40 and 100 GbE technology approaching $3 bil-

lion in sales. Meanwhile, Infonetics Research shows sales of 40 GbE technology sales grew 50% in both Q1 and Q2 of this year. The expan-sion is largely driven by bigger data centers and the move to the cloud, according to researchers.

The university recently upgraded the core of the residential portion

40 GIGABIT ETHERNET: THE MIGRATION BEGINSExperts and early adopters of 40 Gigabit Ethernet share successes and pitfalls. BY SHAMUS MCGILLICUDDY

Infonetics Research shows sales of 40 GbE technology sales grew 50% in both Q1 and Q2 of this year.

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of its campus network with two of Cisco Systems’ new Catalyst 6500-E switches. Today, those core switches are interconnected with multiple 10 GbE links, but traffic is spiking upward and the university will need 40 GbE interconnections soon. Van Ingen is testing a 40 GbE interconnect between the two Cata-lyst 6500s and plans to put two 40 GbE interconnections into produc-tion soon.

The demand for this bandwidth is driven by three factors: The uni-versity is increasing its use of cloud services and cloud storage, video traffic to the student dormitories is growing, and various open source projects that are mirrored on the university’s campus are extremely popular.

“If we don’t keep up with upgrades, the network experience will get worse and worse,” van Ingen said. “If the links actually get saturated before we upgrade, the increased packet loss will lead to error messages in their applications, actions that can’t be completed and lost productivity in general.”

Verisign Inc., the Reston, Va.-based Internet infrastructure pro-vider, which manages two of the Internet’s 13 root servers, will likely transition to 40 GbE within two years, according to Mike Gibbs, Verisign’s network architect. Gibbs and his team beta-tested the 40 GbE capabilities on Cisco’s Catalyst

6500 Supervisor Engine 2T. “The first and most obvious place that I suspect a lot of people will initially install 40 gigabit is in their QA [quality assurance] and lab environ-ments,” he said. “It’s more conve-

nient to have testing tools and load generation tools and interconnects that are single links of large capac-ity, as opposed to many aggregated links.”

Verisign will soon have to replace aggregated 10 GbE links with 40 GbE links, particularly to network service devices like load balancers and firewalls. Today, GbE-capable load balancers and firewall appli-ances are scarce on the market, but the migration will happen. “As capacity for our infrastructure has to grow, as DNS grows, as our denial-of-service product grows, we’re going to need greater capacity between devices,” Gibbs said.

“ If the links actually get saturated before we upgrade, the increased packet loss will lead to error messages in their applications.”

—JEROEN VAN INGEN, network engi neer, University of Twente

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40 GIGABIT ETHERNET: WHEN LINK AGGREGATION IS NO LONGER SUFFICIENT

Link aggregation has been an essen-tial tool for network engineers for years, whether aggregating multiple Gigabit Ethernet links or 10 GbE links. There always comes a time when aggregation is no longer prac-tical, however, and a migration to the next generation of Ethernet is necessary. Enterprises whose busi-nesses are based on network per-formance and reliability will reach a point where link aggregation breaks down, and they will have no choice but to upgrade to 40 GbE.

“There’s a limit to how many single 10-gigabit links we’ll be able to wrap together into an aggregate link,” Gibbs said. “With link aggre-gation, you have a hashing mecha-nism to send traffic across them as equally as possible. Not every ven-dor does that equally well. Because of that, when you start having ven-dors interoperate with each other, you can’t guarantee an equal spread across all those links. So, a single 40-gigabit link ends up being much more preferred.”

Link aggregation is based on the IEEE 802.1ax standard, but the hashing algorithms each vendor uses to load balance traffic across multiple links is unique, according to Dhritiman Dasgupta, senior direc-tor of product marketing at Juniper Networks.

“With 40 Gigabit Ethernet you get guaranteed and dedicated 40-gigabit bandwidth, so hashing algorithms don’t play a part any-more,” Dasgupta said. “[When] predictability is their business, [networking pros] are moving to 40 gigabit. They can’t take a chance on hashing algorithms playing a part in how long transactions take.”

TRANSITIONING TO 40 GIGABIT ETHERNET

As is the case with every next-gen-eration Ethernet standard, the tran-sition from 10 GbE to 40 GbE will not be disruptive, Dasgupta said. From a protocol standpoint, TCP, UDP and Layer 2 and Layer 3 proto-cols remain unchanged.

“The things that need to change are the cabling and the optics at both ends,” he said.

Specifically, enterprises will need to deploy new fiber—OM3 or OM4—for link lengths of up to 100 meters and duplex single-mode fiber (SMF) for links up to 10 kilo-meters. Of course, new transceivers will also become necessary, wheth-er SR4 or LR4.

Many enterprises are already thinking about the path to 40 GbE as they install 10 GbE today, and are rolling out ribbon fiber that can sup-port the higher bandwidth.

While many enterprises install 40 GbE-ready infrastructure dur-

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ing a 10 GbE upgrade to save time and money, those savings will only happen if the networking team maintains the cabling plant prop-erly. Signal loss tolerance for a 40 GbE network is extremely low in comparison to Gigabit Ethernet and 10 GbE, and it can be challenging to achieve an acceptable rate of loss.

“People will connect fiber up and never have cleaned it and never inspected it,” said Ed Gastle, prod-uct line manager for JDS Uniphase Corp. (JDSU), a Milpitas, Calif.-based optical test and measure-ment company. “The [40 GbE] links will come up and they will work, but you’ll be taking errors because your data is getting corrupted.”

Poor fiber maintenance became an issue during Interop Las Vegas in 2011, he added. JDSU provided the testing and measurement for InteropNet that year. That year, the InteropNet network upgraded from Gigabit Ethernet to 10 GbE.

“They had a whole bunch of fiber out, but they hadn’t treated it very well,” he said. “They hadn’t been cleaning and inspecting it. And now they were trying to run 10 giga-bit. Well, guess what? It doesn’t work. Now you have to go through a recovery effort to get your end faces to good enough loss [levels] to support 10 gigabit. We were able to get a few of them back by aggres-sively cleaning them, but it takes a lot of time. And if you have to re-

terminate [the fiber], it takes a lot of money.”

The migration to 40 GbE is even more sensitive to poorly maintained fiber. Enterprises need to inspect and clean the end faces on those fiber links because the next genera-tion of Ethernet will have a much lower loss budget.

“We hear more and more that as these speeds go up, systems are not coming up at all or are coming up and having problems,” Gastle said. “Then we start to troubleshoot and we find that the problem is caused by a poorly maintained end face. They’ve been connected up so many times that dirt and debris has been ground into it and you … have to re-terminate that fiber.”

Connecting dirty fiber to active equipment can also spread damage, he said. Anything short of pristine fiber can pose a risk of damage to the optics, for instance.

SECURING AND MONITORING 40 GIGABIT ETHERNET LINKS

As network engineers deploy 40 GbE switches and routers, eventual-ly they’ll need Layer 4-7 appliances, such as application delivery control-lers, firewalls or WAN optimization controllers, that can handle 40 GbE traffic. They also need evaluate how these devices monitor the network, whether it is for security or perfor-mance.

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“It’s not the link speed that you have to be concerned about,” said Verisign’s Gibbs, who is evaluating 40 Gbps firewalls. “It’s whether or not the systems can actually do the processing of the traffic between them, especially firewalls, where every packet is going to be at least briefly reviewed at a minimum of Layer 3, if not Layer 4, all the way up to Layer 7. That takes a huge amount of computational power.”

Some organizations will want line rate visibility right at the 40 GbE link. The University of Texas at Aus-tin has deployed high-availability (HA) pairs of Cisco Nexus 7000s switches in two data centers, with 40 GbE interlinks between the HA pairs and between the data centers, according to Brent Boggan, regional sales manager at Ixia, a network monitoring vendor based in Cala-basas, Calif., which has helped the school instrument the network for visibility.

Boggan said the university has 40 GbE links in each of two Austin data centers. Ixia put a physical, passive optical 40 Gbps tap on each of those connections. The monitor-ing ports coming out of those taps then flow into a network monitoring switch, the Anue Net Tool Optimiz-er (NTO) 5288, which can process up to 40 Gbps of data at full duplex.

The NTO 5288 then filters, rep-licates and load balances that 40 Gbps flow across multiple 10 Gbps

tools, including multiple intrusion detection appliances like Source-Fire’s Real-time Network Aware-ness tool.

Still, early adopters will have to deal with limitations of existing technology. Many organizations will rely on NetFlow and SNMP for network visibility because line-rate packet analysis will remain a chal-lenge.

The University of Twente will use open source SNMP counters and NetFlow analyzers to maintain vis-ibility on its 40 GbE links, van Ingen said. For packet visibility, he per-forms full packet captures on the 10 GbE links that are aggregated by the Catalyst 6500.

“If we really need to do full packet analysis on a 40 Gbps link, we’ll probably configure a high-end serv-er with a multiport 10 GbE card and see how far that gets us,” he said.

Verisign relies on NetFlow and SNMP to monitor its 10 GbE net-work today and will probably con-tinue that approach as it migrates to

Many organizations will rely on NetFlow and SNMP for network visibility because line-rate packet analysis will remain a chal lenge.

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40 GbE, Gibbs said. But the process is imperfect,

Gibbs acknowledged. Some events will always slip through. These pro-tocols won’t always reveal bursts of traffic going up and down. On the security side, something malicious can slip through very easily.

“You’re looking at patterns to figure things out instead of looking for something inside of a packet,” he said. “It also means any [probing attack] with a single or couple of packets you might miss because it’s outside of your sampling point. It’s a known risk everyone has to deal

with, but it is the side effect of more bandwidth and more speed.”

Mitigating that risk involves a multi-tiered solution for monitoring and security, Gibbs said. Network engineers need to continue watch-ing what’s going on in NetFlow and other sampling technologies, but then have another tier of defense with inspection devices down-stream in the network.

“Don’t just look at these [core] routers,” he said. “If you miss it at the core routers, you should catch it in a net further down in the chain.”n

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DO 100 GBE MANAGEMENT AND MONITORING TOOLS EXIST?

IT MAY BE early days for 100 Gigabit Ethernet, but many service provid-ers have deployed the technology, and now a small but growing num-ber of enterprises are proceeding with it as well. As soon as 100 GbE is in live production, network and security pros will need to manage and monitor these networks. Herein lies the challenge—some manage-ment tools are ready for this next level of ultra-speed, but some clear-ly are not.

Of 15 network management and monitoring vendors contacted for recent research, very few had con-crete products in place or even a near-term roadmap. Yet most are aware of the emerging need for 100 GbE monitoring and management and are exploring how to accommo-date customers.

The difficulty of monitoring 100 GbE networks varies depending on the type of network management tool or strategy. Some network management strategies lend them-selves more easily to adapting to ultra-high speed networks, while others must be heavily transformed. The following is an assessment of existing network management strat-egies and whether they’re ready to handle 100 GbE networks.

n Fault/availability management: Since 100 GbE is delivered via net-work devices, the first objective is to make sure that tools for the network operations center (NOC) are ready to discover and recognize these devices. That will mean recogniz-ing the new interfaces they employ, their topology placement, and their

DO 100 GBE MANAGEMENT AND MONITORING TOOLS EXIST?Vendors are racing to release 100 GbE switching, but network monitoring tools may not be able to keep pace. BY JIM FREY

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ongoing health. These basic capa-bilities are already present in most fault/availability monitoring plat-forms today, particularly among products that have been deployed in service provider environments (i.e. ISPs, mobile operators, hosting providers) where 100G is already in place today. These tools may need to be scaled down for an enterprise network environment.

n Statistics-based performance management: Things get a bit stick-ier when you look at performance management platforms that gather statistics by regular polling of net-work devices. While many metrics will not be directly affected, traffic polling counters may be insufficient for tracking total volume of activity unless those counters are harvested on a much more rapid basis than polling engines are typically con-figured to support. This will not be a problem in the early days of 100 GbE, as total traffic volumes will ini-tially be far less than total capacity, but eventually these tools will need to scale.

n Flow-based security and perfor-mance management: Tools that use technologies such as NetFlow or IPv6 to gather data regarding com-position volume of traffic should be essentially agnostic to 100 GbE, and will be stressed only if traffic volumes rise to a level that results in

flow record volumes beyond a tool’s capacity to collect and analyze. Again, that’s not likely to occur in the near term, as flow-based tools designed for today’s enterprise or service provider environments are already equipped to handle very high volumes of flow record data.

n Packet-based security and perfor-mance management: Here’s where we run into a major problem. Packet inspection tools are the heavy lift-ers of the management tools sector, and they face the greatest technical challenge when trying to accom-modate increased network speeds. There are a few essential parts to this challenge—getting to the pack-ets, distributing the packets for analysis, and analyzing the packets. There are no packet analysis tools available today that can directly support 40 GbE, let alone 100 GbE, at full line rates. Many have certified full 10 GbE support and a few offer 40 GbE interfaces, but none have addressed 100 GbE at this time.

SCALING PACKET INSPECTION TOOLS TO MEET 100 GBE NETWORKS

The only viable approach to 100 GbE network management today is adapt existing tools that are today only rated to 10 GbE. This requires a two-part process.

The first step is gathering packets at 100 GbE. There are currently two

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techniques primarily used for gath-ering packets for analysis – TAP and SPAN (a.k.a. port mirroring.) SPAN is a function of the network device itself, but taps must be upgraded to support 100 GbE. The good news here is that taps are already available for 100 GbE. NetOptics released the 100G Flex Tap back in September, and the company claims deployments are already underway in mobile telco, ISP and hosting provider shops. ONPATH (which is being acquired by NetScout) is also shipping 100G-rated, Layer 1 access devices in the form of Optical Blade for its 3900 switch family, mostly to testing environments. Other L1 vendors have this on their roadmaps, so expect more options coming in 2013.

The second element of deep packet inspection is distributing

packets at 100G. This is the job of network monitoring switches (a.k.a. network packet brokers), which adapt traffic from 100 GbE interfaces over to 10 GbE interfaces to manage the torrent of packets via load balancing, slicing, filtering, etc. The idea is to prevent analy-sis tools from being overwhelmed. While 100 GbE is on the roadmap of some vendors (some say they’ll have product in early 2013), Endace was the first to productize and ship a solution. The EndaceAccess 100 provides L1 adaptation and load balancing so that 10G-rated packet analysis tools can be deployed to monitor 100 GbE links. The solution is deployed and being used in pro-duction by Endace customers today.

Other vendors are working on 100 GbE network monitoring switching as well. For example, on Novem-ber 1, 2012, Gigamon announced it would be demonstrating 100G aggregation and connections later in the month. Expect to see others making announcements late this year and early next.

For many, 100 GbE is far off in the future, so there is no immediate need to worry about how to man-age it. But for those at this bleeding edge, core fault/availability tools are ready now, and recent introduc-tions by companies such as NetOp-tics, ONPATH, and Endace, place packet-based security and perfor-mance monitoring within reach. n

MORE ON NETWORK MONITORING TOOLS

n Deep packet inspection tools: Proxy vs. stream-based

n Cloud monitoring tools: Using Wireshark in the cloud

n Network diagnostics that see through virtualization

n Network performance testing for a 40 GbE upgrade

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WILL WE EVER NEED 400 GIGABIT ETHERNET ENTERPRISE NETWORKS?

THOUGH 10 GIGABIT ETHERNET (GbE) is just at the beginning of widespread uptake, there’s already plenty of talk in the market about the need for 40 and 100 GbE in the enterprise. In the middle of all this, do we need to consider the potential for 400 Giga-bit Ethernet in the WAN and LAN? The answer is, plainly, yes.

The IEEE has just formed a work-ing group to determine whether there will be need for 400 GbE or Terabit Ethernet development. But we are already some looming use cases—even in the enterprise LAN—that will drive the need for 400 Gigabit Ethernet.

In general, high-speed standards like 400 GbE or even Terabit Eth-ernet are applied deeper in the network where traffic has been aggregated. For now, computer and

storage interface standards define transfer rates well below 100 GbE, so that won’t cause demand. But since the edge of the network is getting faster, it would be sensible to assume that this higher edge traffic would force up speeds in the metro/core aggregation network as well.

Modern networks, whether they span the globe or only the data center, are built on a hierarchy of devices, with “deeper” switches or routers networking the edge devices together for full connectivity. This has encouraged the use of succes-sively faster trunks as port speeds have increased. The trend makes it logical to assume that future LAN switches or WAN switch/routers will need 400 GbE or faster. More traffic, more capacity. But traffic

WILL WE EVER NEED 400 GIGABIT ETHERNET ENTER-PRISE NETWORKS?With 40 and 100 Gigabit Ethernet so new, what could possibly drive the need for 400 Gigabit Ethernet in the enterprise? Hint: It’s not just the WAN. BY TOM NOLLE

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doesn’t impact the WAN or LAN uniformly—and therefore the needs may be vastly different in the two network types.

IN THE WAN, THINK FASTER ETHERNET FOR OPTICAL SWITCHING

In the WAN, the largest source of additional traffic in the future net-work will likely be content. That content is increasingly cached in a content delivery networks (CDNs) or in content farms in each metro area. This means that while the growth of access bandwidth is likely to continue, and this increased edge capacity will demand greater capac-ity in the metro area for aggrega-tion, the majority of content traffic will stop in the metro cache and never reach the core at all. In that case, within a metro there’s less traffic to aggregate, which means

there’s less pressure on Ethernet performance.

It’s likely that there will be greater need for faster Ethernet interfaces on optical switches and optical point-to-point paths in metro net-working. Almost all traffic in a metro network goes one place—the metro concentration point, where it’s con-nected to a cache, a data center or the core network. Ethernet routing or switching based on destination address is hardly useful when all the traffic is headed in the same direction.

Even when traffic does reach the core, which would be the case for business traffic and especially video conferencing, that traffic may not drive the kind of changes everyone expects at the equipment level. Operators have been looking for alternatives to adding more lay-ers of switch/router aggregation, including the optical transport net-work (OTN) or the routerless core. In both of these alternative network architectures, metro areas are con-nected to each other in a mesh rather than to deeper-level electri-cal devices like routers (hence the term routerless). Because traffic is limited to each metro area partner, it’s less likely this connection would demand a radical increase in Eth-ernet speeds. However, even when traffic growth does drive faster Eth-ernet interfaces, they’re again more likely to be used on optical devices than on Ethernet switches or routers.

MORE ON NEXT-GENERATION ETHERNET

n IEEE explores new standards for ultra-fast Ethernet

n 40 Gigabit Ethernet in the data center: Migration best practices

n Research institute deploys 100 Gigabit Ethernet from core to closet

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SURPRISE, SURPRISE: 400 GIGABITETHERNET NEEDED FOR THE LAN

In the LAN, it’s harder to discard the notion that uniform connectivity is needed. Cloud computing encour-ages the creation of dense, highly connected, data centers. Cloud applications are often more compo-nentized and horizontally integrated than traditional applications, which makes traditional multi-tiered LAN switching performance more prob-lematic. In a cloud data center, even 10 GbE server/storage interfaces connected in a four- or five-layer structure might drive switch inter-face speeds to 400 GbE or more in the deeper layers.

While intra-data-center con-nectivity seems to be migrating to fabric switching, and away from traditional stacks of LAN switches, that may not preclude the need for faster, 400 GbEd. Fabric switches today either have no internal trunk connections, or base their connec-tions on standards other than Eth-

ernet. But when clouds are created by linking multiple data centers over fiber, a super-Ethernet connection is almost inevitable.

The bottom line is that we need faster Ethernet. Faster Ethernet will connect cloud data centers and will support optical metro aggregation and OTN-based cloud core net-works. While these missions are more limited than that of 1 GbE, for example, they will be of paramount importance to network design in the future, and so it is very likely that the race for faster Ethernet will con-tinue. n

Faster Ethernet will connect cloud data cen-ters and will sup port optical metro aggrega-tion and OTN-based cloud core networks.

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ABOUT THE AUTHORS

Networking Evolution is a SearchNetworking.com e-publication.

Kate Gerwig Editorial Director

Rivka Gewirtz Little Executive Editor

Shamus McGillicuddy Director of News and Features

Kara Gattine Senior Managing Editor

Linda Koury Director of Online Design

Scott Kelly Associate Publisher

skelly@techtarget.com

TechTarget 275 Grove Street, Newton, MA 02466

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Shamus McGillicuddy is the director of news and features for TechTarget Networking Media. He writes about networking, security, data centers, net-work management and other topics for SearchNetworking.com. He also man-ages overall news coverage for TechTar-get’s other networking sites, including SearchUnifiedCommunications.com, SearchEnterpriseWAN.com and Search-CloudProvider.com. Before joining Tech-Target in 2006, Shamus was an award-winning reporter for The Patriot Ledger, a daily newspaper in Massachusetts.

Jim Frey is the managing research direc-tor at Enterprise Management Associ-ates. Frey has 24 years of experience in the computing industry developing, deploying, managing, and market-ing software and hardware products, with the last 18 of those years spent in network management, straddling both enterprise and service provider sectors.

Tom Nolle is a strategic egghead—someone who first wants to know the truth, no matter what it is, and then wants to explain it in a way that reaches everyone who cares to know it. He’s an analyst in telecommunications, media and technology, and a former software architect who now works to blend tech-nology detail and business reality. He has more than 30 years of experience as an author and analyst, covering the most complicated and important develop-ments in the industry. Nolle is president of CIMI Corp., a strategic consulting firm specializing in telecom and data commu-nications since 1982. He is the publisher of Netwatcher, a journal addressing advanced telecom strategy issues.