Jumbo frame

Abstract: With 100G technologies standardized, in the context of both Ethernet and the optical transport network (OTN), 100G router ports and 100G optical transport interfaces are commercially available. At the same time, heavily data-centric users are starting to ask for higher-rate interfaces. First speculations include 400G as well as 1T as the next possible Ethernet standards. In this article we discuss interface technology options for Ethernet and OTN beyond 100G in light of the current 100G standards, taking into account likely evolution paths of interface technologies over the next 10 years.

Abstract: Ethernet, a 10 Mbit/sec CSMA/CD network, is one of the most successful LAN technologies. Considerable confusion exists as to the actual capacity of an Ethernet, especially since some theoretical studies have examined operating regimes that are not characteristic of actual networks. Based on measurements of an actual implementation, we show that for a wide class of applications, Ethernet is capable of carrying its nominal bandwidth of useful traffic, and allocates the bandwidth fairly. We discuss how implementations can achieve this performance, describe some problems that have arisen in existing implementations, and suggest ways to avoid future problems.

Abstract: Modern interconnects like Myrinet and Gigabit Ethernet offer Gb/s speeds which has put the onus of reducing the communication latency on messaging software. This has led to the development of OS bypass protocols which removed the kernel from the critical path and hence reduced the end-to-end latency. With the advent of programmable NICs, many aspects of protocol processing can be offloaded from user space to the NIC leaving the host processor to dedicate more cycles to the application. Many host-offload messaging systems exist for Myrinet; however, nothing similar exits for Gigabit Ethernet. In this paper we propose Ethernet Message Passing (EMP), a completely new zero-copy, OS-bypass messaging layer for Gigabit Ethernet on Alteon NICs where the entire protocol processing is done at the NIC. This messaging system delivers very good performance (latency of 23 us, and throughput of 880 Mb/s). To the best of our knowledge, this is the first NIC-level implementation of a zero-copy message passing layer for Gigabit Ethernet.

Abstract: Simplicity, cost effectiveness, scalability, and the economies of scale make Ethernet a popular choice for local area networks, as well as for storage area networks and increasingly metropolitan-area networks. These applications of Ethernet elevate it from a LAN technology to a ubiquitous networking technology, thus prompting a rethinking of some of its architectural features. One weakness of existing Ethernet architecture is its use of single spanning tree, which, while useful at avoiding routing loops, leads to low link utilization and long failure recovery time. To apply Ethernet to cluster networks and MANs, these problems need to be addressed. We propose a multi-spanning-tree Ethernet architecture, called Viking, that improves both aggregate throughput and fault tolerance by exploiting standard virtual LAN technology in a novel way. By supporting multiple spanning trees through VLAN, Viking makes the most of the inherent redundancies in most mesh-like networks and delivers a multi-fold throughput gain over single-spanning-tree Ethernet with the same physical network topology. It also provides much faster failure recovery, reducing the down-time to a sub-second range from that of multiple seconds in single-spanning-tree Ethernet architecture. Finally, based only on standard mechanisms, Viking is readily implementable on commodity Ethernet switches without any firmware modifications.