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Getting Closer to 99.9999% Network Uptime


Back in May 2002, Cisco Systems announced new software for its 12000 series routers, Globally Resilient IP (GRIP). GRIP is meant to eliminate data loss on the network even if there are circuit failures or human errors. Not a bad trick if they can do it.

Juniper Networks, of course, immediately replied that said they have had “zero packet loss” on their routers since 1998. Without making that boastful claim, Alcatel had announced that its non-stop ACEIS router would be out later this year.

What is going on here? Has information loss become so crucial? Is there a real demand for highly available networks? Or, are the network OEMs, fighting against a horrid economy, simply creating a high-tech version of the washing powder commercials of my early 1970s childhood when Tide or Bold would roll out their “new-improved” products.

Some of it is smoke and mirrors. Sorry Juniper, no one always gets a perfect score in packet exchanging. As for Cisco and Alcatel? They won’t have product out until the 3rd quarter. Other companies, better known for their work with ATM, such as Nortel, and Terabit switching, Avivi, are also moving into the extreme reliability market.

Is there really a market for IP networking that strives to reach, and surpass, 99.9999% reliability and uptime? As a matter of fact there it is, but it’s not the traditional Internet, or even extranet or intranet markets. It’s the carrier market that supplying the demand for previously unheard of uptimes for IP.

In the past, IP has always been a best-effort networking solution. IP would work on anything-even carrier pigeons (RFC-3043)-but while the message more often than not would get through, sometimes your connection would be slow, sometimes it would be fast, and sometimes you’d wonder if the backbone provider really was using carrier pigeons.

Because of its low cost and increase in reliability, IP has become more and more attractive to all carriers though, and not just ISPs and LAN administrators. So it is that, according to David Willis, Meta Group’s VP of Global Networking Strategy, that there really is “clearly a need for more reliable IP network. Carriers are more migrating more and more of their traffic to IP traffic. AT&T carrying more and more voice on their IP backbone.”

In the past, even backbone providers and major ISPs have used the slogan, “every router needs a buddy.” What that meant for those who don’t spend their times in American Network Operations Centers is that every router had a hot spare running beside it. That was fine, if when a failure finally happens your customers could live with minutes or hours as the stand-by routers built up its route tables and took over the network load.

When your customer is Cable & Wireless, Equant, Infonet, or WorldCom, though, minutes don’t cut it and hours are completely unacceptable. An acceptable outage time in SONET for voice, according to Seamus Crehan Senior Analyst, Dell’Oro group, is a sub-15millisecond recovery. Why such a harsh standard? Because breaks in voice traffic directly impact voice-carriers’ bottom line.

Unfortunately, according to Tim Smith, an analyst for Gartner Dataquest, IP that can handle that kind of load isn’t here yet. Willis agrees, “This wave of carrier-grade IP services is new movement. It’s not fully ready yet.

So why are the carriers making this move? Cost. IP, even when running on the highest of high-end routers, looks to be cheaper than SONET and ATM in the long run. As Val Oliva L2/3 Product Marketing Manager for Foundry Networks and a member of the 10 GEA (10-Gigabit Ethernet Alliance) Board of Directors says, “Carriers looking for ways to increase profit, they will need a new set of systems that can lower their system cost and cost of operations to increase returns.”

And, sooner rather than later, IP will provide those new systems. Willis thinks, “Cisco, which always leads in anything related to core routing, will lead. Juniper, which had been taking market share from Cisco, but is now falling back, will also be in the hunt. Alcatel and Nortel, which already have strong carrier relations thanks to their ATM switching background, will also be in the race.” He also adds that any company that’s very active in MultiProtocol Label Switching (MPLS) will have a shot.

Another question in carrier-grade IP will be whether the future will be IP running on top of existing ATM and SONET networks or on Ethernet. “Ethernet,” You ask? Yes, Ethernet.

10-Gigabit Ethernet (GbE) will be emerging as a serious competitor for OC-192 SONET by the end of 2002. If anything, 10-GbE will be in place before high reliability IP routers become commonplace. In the event, both technologies are likely to support each other in advancing IP’s case to carrier-grade customers.

Only time will tell if Oliva is right when she says that, “Ethernet is IP’s best friend, and in the end, IP wants Ethernet.” What is certain is that IP is coming to the carrier world.

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