Quanta Cloud Technology QuantaMesh QNOS5, Configuration Manual

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1.1.39. FIP Snooping
The FCoE Initialization Protocol (FIP) is used to perform the functions of FC_BB_E device discovery,
initialization, and maintenance. FIP uses a separate EtherType from FCoE to distinguish discovery,
initialization, and maintenance traffic from other FCoE traffic. FIP frames are standard Ethernet size (1518
Byte 802.1q frame), whereas FCoE frames are a maximum of 2240 bytes.
FIP snooping is a frame inspection method used by FIP Snooping Bridges to monitor FIP frames and apply
policies based upon the L2 header information in those frames.
FIP snooping allows for:

Auto-configuration of Ethernet ACLs based on information in the Ethernet headers of FIP
frames.

Emulation of FC point-to-point links within the DCB Ethernet network.

Enhanced FCoE security/robustness by preventing FCoE MAC spoofing.

The role of FIP snooping-enabled ports on the switch falls under one of the following types:
o
Perimeter or Edge port (connected directly to a Fibre Channel end node or ENode).
o
Fibre Channel forwarder (FCF) facing port (that receives traffic from FCFs targeted to
the ENodes).
Note: The FIP Snooping Bridge feature supports the configuration of the perimeter port role and FCF-
facing port roles and is intended for use only at the edge of the switched network.
The default port role in an FCoE-enabled VLAN is as a perimeter port. FCF-facing ports are configured by the
user.
1.1.40. ECN Support
Explicit Congestion Notification (ECN) is defined in RFC 3168. Conventional TCP networks signal congestion
by dropping packets. A Random Early Discard scheme provides earlier notification than tail drop by
dropping packets already queued for transmission. ECN marks congested packets that would otherwise
have been dropped and expects an ECN capable receiver to signal congestion back to the transmitter
without the need to retransmit the packet that would have been dropped. For TCP, this means that the TCP
receiver signals a reduced window size to the transmitter but does not request retransmission of the CE
marked packet.
QNOS implements ECN capability as part of the WRED configuration process. It is configured as parameter
in the
random-detect command. Eligible packets are marked by hardware based upon the WRED
configuration. The network operator can configure any CoS queue to operate in ECN marking mode and can
configure different discard thresholds for each color.
1.2. Security Features
1.2.1. Configurable Access and Authentication Profiles