Calling ethernet a success story is the understatement of the year. Ethernet is about as ubiquitous as you can get. Whatever happened to ARCnet, AppleTalk, Token Ring, MAP, FDDI, and the many other local-area networks (LANs)? Not only has Ethernet replaced them all, but now it's moving into every other area of networking, including metropolitan-area networks (MANs or metros), storage-area networks (SANs), and wide-area networks (WANs). But it doesn't stop there. Ethernet also owns the wireless networking space, big time.
Talk about a dominant technology. When they were inventing Ethernet, Bob Metcalfe and his colleagues didn't realize they were creating the ultimate networking solution (see "What Is This Thing They Call Ethernet?," p. 48). It has changed some over nearly 30 years, but so has the technology, and it's still evolving as you read this article.
Whenever we think of Ethernet, most of us picture the typical enterprise LAN running 100 Mbits/s over CAT5 twisted-pair switched stars. Almost everyone has one now. A few Token Ring LANs still exist, yet even these are slowly giving way to Ethernet's relentless onslaught. But if you haven't been paying close attention, you may not know that Ethernet has worked its way into almost every other niche of networking. Consider these applications:
- MANs: The newer 1-Gbit Ethernet (1GE), fiber-optics version of Ethernet can carry more traffic over longer distances than those typical even for large campus LANs. As a result, some companies have used this new technology to open new businesses in the metro network market. An example is Yipes, who is doing a brisk business of connecting remote LANs via MANs. The newer 10-Gbit Ethernet (10GE) is another candidate for this market. Plus, the Resilient Packet Ring (RPR) effort by IEEE working group 802.17 and vendors like Infineon should ultimately provide the manageability, quality of service (QoS), and security necessary for Ethernet to succeed as a carrier-class metro networking technology.
- WANs: The 1GE and, especially, the 10GE capabilities could find applications in the WAN market. This is now dominated by Sonet, which will no doubt hold on to most of that business. But as we move more to the Internet protocol (IP), Ethernet will become even more attractive. It might eventually take some market share from OC-192 Sonet when carriers begin offering services that let companies connect remote LANs at higher speeds with lower-cost Ethernet switches and without protocol translation.
- Home networking: Only now is this market beginning to take off. Some early home networkers have actually wired their homes with CAT5 twisted pair and installed an inexpensive Ethernet network. Today, many newer homes are routinely wired with CAT5 along with ac power, telephone, cable TV, and security wiring.
- Wireless Ethernet: This Ethernet business segment is growing significantly in the enterprise and the home. Wireless' flexibility is now eminently affordable at all levels. Significant devel- opment continues in this arena, so there's more to come.
- Industrial Ethernet: Many different specialty and proprietary networks for devices, sensors, controllers, and the like have always made up the in-dustrial networking market. But today, most of these specialty networks are giving way to Ethernet due to its wide availability, low cost, and compatibility with adjacent business LANs.
Keepers of the standards for widely used industrial networks are finding they can encapsulate their protocols into TCP/IP and transmit them via standard 100-Mbit/s UTP/CAT5 Ethernet. Some industrial standards now possible with Ethernet are DeviceNet/ControlNet/EtherNet/IP, Profibus-DP/Profinet, Modbus, and Foundation Fieldbus H1/HSE. Security and real-time issues not solved by Ethernet are being handled. But plants and factories are enjoying the high speed, low cost, wide availability, and compatibility with office LANs Ethernet offers.
- SANs: As storage needs increase in all business sectors because of massive e-mail files, more multimedia data, and the need to have faster, easier access to data, SANs are growing in number. SCSI is still the most widely used SAN interface, but the popular Fibre Channel (FC) standard has grown dramatically over the years. FC's 1-Gbit and now 2-Gbit rates make high-speed access possible, but it is expensive.
Ethernet is slowly working its way into this sector. A forthcoming ITEF standard called Internet SCSI (iSCSI) encapsulates the SCSI protocol into IP packets and transmits them via Ethernet. This provides higher speeds than FC and eliminates FC's distance limitations (10 km at 1 Gbit/s). Data access with iSCSI can be to a nearby data center or to storage anywhere worldwide via the Internet. While FC is fighting back with the development of a 10-Gbit/s version and its own FC-over-Internet solution, most expect FC to eventually fade away as 10GE and iSCSI make SANs faster, cheaper, and fully compatible with existing LANs.
Ethernet is a hot market. With over 1 billion ports already in place and the growth continuing, it's no wonder that we keep seeing even more new product activity. With so many new Ethernet products appearing almost daily, it's hard to keep track.
1GE Standards: Back in 1998, the 1GE standard was approved. It offers both copper and fiber media options (Table 1). The copper option has become the "sweet spot" in the market simply because users can implement 1GE on existing CAT5 unshielded twisted pairs (UTP) now used for 100-Mbit/s Ethernet. 1GE employs four twisted pairs to get the 1-Gbit/s rate up to 65 m. This offers a fast, inexpensive, and easy upgrade path to 1 Gbit/s for enterprise LANs. High speed is the draw, but 1GE also permits the LAN to handle more users and lets network-attached storage (NAS) systems be accessed at a reasonable speed.
Semiconductor vendors now provide chips that make it possible to include affordable 1GE ports on PCs. These chip sets implement the 10/100 Ethernet ports common on most PCs today but also include the 1-Gbit/s capability. Soon, 10/100/1000 ports will be standard on most PCs and laptops. Just as 100-Mbit/s Fast Ethernet eventually became the standard when its pricing fell into the $100 per port range, 1GE is expected to become the desktop standard as its cost continues to drop.
An example of a 1GE chip set is Massana's Everest series introduced earlier this year. The MA1110 is a single-port device while the MA1140 and MA1141A are quad-port devices. Made with 0.18-µm CMOS, these chips fully comply with the IEEE-802.3, -802.3u, and -802.3ab standards, letting them handle 10BaseT/100BaseTX/1000BaseT connections.
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