Cisco Cisco MDS 9000 24-port 4-Gbps Fibre Channel Switching Module White Paper
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Current options for storage protocols that can use an Ethernet transport fabric include Fibre Channel over
Ethernet (FCoE), Internet SCSI (iSCSI) or Network File System (NFS).
Ethernet (FCoE), Internet SCSI (iSCSI) or Network File System (NFS).
FCoE implementations today can interoperate with traditional Fibre Channel (FC) networks, allowing for a
gradual change from separate, dedicated SAN to converged SAN/LAN over time.
gradual change from separate, dedicated SAN to converged SAN/LAN over time.
The benefits of such convergence would potentially include reduced cost of acquisition for network
equipment, less equipment overall from shared redundancy, reduced overall network staffing, and lower
complexity of management.
equipment, less equipment overall from shared redundancy, reduced overall network staffing, and lower
complexity of management.
Barriers to this convergence currently include: organizational issues with change of reporting and
budgeting structures that are likely to be requirements for this convergence, resistance to the technology
change, and some degree of confusion in the market about just what SAN/LAN convergence will look like.
budgeting structures that are likely to be requirements for this convergence, resistance to the technology
change, and some degree of confusion in the market about just what SAN/LAN convergence will look like.
Data centers are becoming increasingly complex as businesses rely more heavily on IT for critical operations,
data growth is tremendous, and budgets are tight. Constant availability is a requirement for most firms, limiting
windows for maintenance and lowering tolerance for outages.
data growth is tremendous, and budgets are tight. Constant availability is a requirement for most firms, limiting
windows for maintenance and lowering tolerance for outages.
For years, data traffic from servers to centralized storage has been carried on specialized FC networks, designed
to provide maximum performance and availability characteristics. Conversely, application networking for user-
to-server and server-to-server traffic has run on Ethernet links. Ubiquitous, fairly easy to manage, and low cost,
Ethernet has become the LAN network standard worldwide, displacing most every alternative. Purchase,
deployment, and management of these two networks have been completely separate, with different teams
concentrating on each and practically no crossover of tools, methodologies, or operations.
to provide maximum performance and availability characteristics. Conversely, application networking for user-
to-server and server-to-server traffic has run on Ethernet links. Ubiquitous, fairly easy to manage, and low cost,
Ethernet has become the LAN network standard worldwide, displacing most every alternative. Purchase,
deployment, and management of these two networks have been completely separate, with different teams
concentrating on each and practically no crossover of tools, methodologies, or operations.
Recent innovations in Ethernet networking present the possibility of network unification through the use of a
single technology for both SAN and LAN. Advances in Ethernet technology and the maturation of protocols such
as iSCSI and FCoE offer deterministic performance, low latency, and constant data availability on Ethernet. An
enhanced lossless version of Ethernet is at the heart of enabling FCoE, which offers current users of FC SANs a
path to move to network convergence while maintaining zoning practices, skill sets, and management tools that
are already familiar. On the server side, the prospect of shared redundant ports for both front-end LAN traffic as
well as back-end SAN networking promises cost savings as well as an increased ability to virtualize server I/O.
The adoption path of FCoE is manifesting in two phases, motivated by the availability of supporting technology
from network, server, and storage vendors; Forrester sees the two phases of adoption emerging along the
following lines:
single technology for both SAN and LAN. Advances in Ethernet technology and the maturation of protocols such
as iSCSI and FCoE offer deterministic performance, low latency, and constant data availability on Ethernet. An
enhanced lossless version of Ethernet is at the heart of enabling FCoE, which offers current users of FC SANs a
path to move to network convergence while maintaining zoning practices, skill sets, and management tools that
are already familiar. On the server side, the prospect of shared redundant ports for both front-end LAN traffic as
well as back-end SAN networking promises cost savings as well as an increased ability to virtualize server I/O.
The adoption path of FCoE is manifesting in two phases, motivated by the availability of supporting technology
from network, server, and storage vendors; Forrester sees the two phases of adoption emerging along the
following lines:
The first phase involves modification of the I/O stream at the server. Storage vendors have been somewhat
slow to adopt FCoE capabilities directly in the array. As an interim step toward full network unification,
common network interfaces for both LAN and SAN traffic from servers have been available in advance of
storage array support. Called converged network adaptors (CNAs), these new interfaces allow servers to
use the same redundant ports for both types of traffic, with load balancing and prioritization as part of the
common network interfaces for both LAN and SAN traffic from servers have been available in advance of
storage array support. Called converged network adaptors (CNAs), these new interfaces allow servers to
use the same redundant ports for both types of traffic, with load balancing and prioritization as part of the