Administrator Guide

Ensure Robustness in a Converged
Ethernet Network
Fibre Channel networks used for SAN traffic employ switches that operate as trusted devices. To
communicate with other end devices attached to the Fibre Channel network, end devices log into the switch
to which they are attached.
Because Fibre Channel links are point-to-point, a Fibre Channel switch controls all storage traffic that an end
device sends and receives over the network. As a result, the switch can enforce zoning configurations, ensure
that end devices use their assigned addresses, and secure the network from unauthorized access and denial-
of-service (DoS) attacks.
To ensure similar Fibre Channel robustness and security with FCoE in an Ethernet cloud network, FIP
establishes virtual point-to-point links between FCoE end-devices (server ENodes and target storage devices)
and FCoE forwarders (FCFs) over transit FCoE-enabled bridges.
Ethernet bridges commonly provide ACLs that can emulate a point-to-point link by providing the traffic
enforcement required to create a Fibre Channel-level of robustness. You can configure ACLs to emulate
point-to-point links, providing control over the traffic received or transmitted into the switch. To
automatically generate ACLs, use FIP snooping. In addition, FIP serves as a Layer 2 protocol to:
• Operate between FCoE end-devices and FCFs over intermediate Ethernet bridges to prevent
unauthorized access to the network and achieve the required security.
• Allow transit Ethernet bridges to efficiently monitor FIP frames passing between FCoE end-devices and
an FCF. To dynamically configure ACLs on the bridge to only permit traffic authorized by the FCF, use
the FIP snooping data.
FIP enables FCoE devices to discover one another, initialize and maintain virtual links over an Ethernet
network, and access storage devices in a storage area network (SAN). FIP satisfies the Fibre Channel
requirement for point-to-point connections by creating a unique virtual link for each connection between an
FCoE end-device and an FCF via a transit switch.
FIP provides functionality for discovering and logging into an FCF. After discovering and logging in, FIP allows
FCoE traffic to be sent and received between FCoE end-devices (ENodes) and the FCF. FIP uses its own
EtherType and frame format. The following illustration shows the communication that occurs between an
ENode server and an FCoE switch (FCF).
The following table lists the FIP functions.
Table 16. FIP Functions
FIP Function Description
FIP VLAN discovery FCoE devices (ENodes) discover the FCoE VLANs on
which to transmit and receive FIP and FCoE traffic.
FIP discovery FCoE end-devices and FCFs are automatically
discovered.
FCoE Transit 338