Under the International Standards Organization's Open Systems Interconnection (OSI) model, Ethernet is fundamentally a Layer 2 protocol. 10 Gigabit Ethernet uses the IEEE 802.3 Ethernet Media Access Control (MAC) protocol, the IEEE 802.3 Ethernet frame format, and the minimum and maximum IEEE 802.3 frame size.
Just as 1000BASE-X and 1000BASE-T (Gigabit Ethernet) remained true to the Ethernet model, 10 Gigabit Ethernet continues the natural evolution of Ethernet in speed and distance. Since it is a full-duplex only and fiber-only technology, it does not need the carrier-sensing multiple-access with collision detection (CSMA/CD) protocol that defines slower, half-duplex Ethernet technologies. In every other respect, 10 Gigabit Ethernet remains true to the original Ethernet model.
An Ethernet PHYsical layer device (PHY), which corresponds to Layer 1 of the OSI model, connects the media (optical or copper) to the MAC layer, which corresponds to OSI Layer 2. Ethernet architecture further divides the PHY (Layer 1) into a Physical Media Dependent (PMD) and a Physical Coding Sublayer (PCS). Optical transceivers, for example, are PMDs. The PCS is made up of coding (e.g., 64/66b) and a serializer or multiplexing functions.
The 802.3ae specification defines two PHY types: the LAN PHY and the WAN PHY (discussed below). The WAN PHY has an extended feature set added onto the functions of a LAN PHY. These PHYs are solely distinguished by the PCS. There will also be a number of PMD types.
The accelerating growth of worldwide network traffic is forcing service providers, enterprise network managers and architects to look to ever higher-speed network technologies in order to solve the bandwidth demand crunch. Today, these administrators typically use Ethernet as their backbone technology. Although networks face many different issues, 10 Gigabit Ethernet meets several key criteria for efficient and effective high-speed networks:
One of the keys to Ethernet's success is the widespread interoperability between vendors. In keeping with its mission to provide resources to establish and demonstrate multi-vendor interoperability of 10 Gigabit Ethernet products, the 10 GEA hosted the world's largest 10 Gigabit Ethernet Interoperability Network in May, 2002. The live, multi-vendor network was on display at the NetWorld+Interop trade show in Las Vegas, Nevada. The network will also be on display at SuperComm, June 4-7, 2002 in Atlanta Georgia.
Comprised of products from 23 vendors, the network included a comprehensive range of products: systems, test equipment, components and cabling. The end-to-end 10GbE network was over 200 kilometers long and showcased five of the seven PMD port types specified in the IEEE 802.3ae draft: 10GBASE-LR, 10GBASE-ER, 10GBASE-SR 10GBASE-LW and 10GBASE-LX4. The network boasted 10 network hops, 18 10 GbE links, and represented all aspects of the technology; WAN, MAN and LAN.
As part of the demonstration 12 companies showed chip-to-chip communication over the IEEE 802.3ae XAUI interface. The collection of products and technologies illustrate years of industry collaboration and signal to the market that 10 Gigabit Ethernet is ready to be deployed and implemented into networks around the world.
Vendors and users generally agree that Ethernet is inexpensive, well understood, widely deployed and backwards compatible from Gigabit switched down to 10 Megabit shared. Today a packet can leave a server on a short-haul optic Gigabit Ethernet port, move cross-country via a DWDM (dense wave division multiplexing) network, and find its way down to a PC attached to a “thin coax" BNC (Bayonet Neill Concelman) connector, all without any re-framing or protocol conversion. Ethernet is literally everywhere, and 10 Gigabit Ethernet maintains this seamless migration in functionality.
Gigabit Ethernet is already being deployed as a backbone technology for dark fiber metropolitan networks. 10 Gigabit Ethernet interfaces, optical transceivers and single mode fiber, service providers will be able to build links reaching 40km or more.
With 10 Gigabit backbones installed, companies will have the capability to begin providing Gigabit Ethernet service to workstations and, eventually, to the desktop in order to support applications such as streaming video, medical imaging, centralized applications, and high-end graphics. 10 Gigabit Ethernet will also provide lower network latency due to the speed of the link and over-provisioning bandwidth to compensate for the bursty nature of data in enterprise applications.
10 Gigabit Ethernet in the Storage Area Network Additionally, 10 Gigabit Ethernet will provide infrastructure for both network-attached storage (NAS) and storage area networks (SAN). Prior to the introduction of 10 Gigabit Ethernet, some industry observers maintained that Ethernet lacked sufficient horsepower to get the job done. Ethernet, they said, just doesn't have what it takes to move “dump truck loads worth of data." 10 Gigabit Ethernet, can now offer equivalent or superior data carrying capacity at similar latencies to many other storage networking technologies including 1 or 2 Gigabit Fiber Channel, Ultra160 or 320 SCSI, ATM OC-3, OC-12 & OC-192, and HIPPI (High Performance Parallel Interface). While Gigabit Ethernet storage servers, tape libraries and compute servers are already available, users should look for early availability of 10 Gigabit Ethernet end-point devices in the second half of 2001.
There are numerous applications for Gigabit Ethernet in storage networks today, which will seamlessly extend to 10 Gigabit Ethernet as it becomes available. These include: