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AND PRODUCT DESCRIPTIONS AT ANY TIME, WITHOUT NOTICE.
T4 - Fourth-Generation Protocol Offload Engine
The T4 is Chelsio’s fourth‐generation TCP offload (TOE) design,
third‐generation iSCSI design, and second‐generation iWARP (RDMA)
implementation. For the server connection, the T4 chip includes a PCI
Express v2.0 ×8 host interface. With support for the 5Gbps Gen2 data
rate, the PCIe interface provides up to 32Gbps of bandwidth to the
server. T4 also adds support for PCIe I/O virtualization. Most of T4
features are enhanced versions of those found in T3. Features that
carry over from T3 include stateless offloads, packet filtering (fire-
wall offload), and traffic shaping (media streaming).
Robust, Proven Solution
Subjected to thousands of hours of compatibility testing, over mul-
tiple years of stress testing by several OEM test suites and produc-
tion deployments in servers, storage systems and cluster computing,
Chelsio’s robust, stable protocol offload technology delivers proven
performance in a wide range of environments. The T420-CX is gen-
erations ahead of competing products.
Physical and Environmental
Dimensions without bracket:
6.6 in. x 2.71 in. or 16.76 cm x 6.88 cm
Operating Temp: 0 to 55ºC or 32 to 131ºF
Operating Humidity: 5 to 95%
Typical power consumption: 12W
Software Drivers
Chelsio offers a full suite of protocol software and drivers with the
T420-CX adapters. See www.chelsio.com/support for latest info. The
software supports operation in both protocol-offload and non-
offload modes.
Chelsio Communications www.chelsio.com sales@chelsio.com +1-408-962-3600
Packet Switching and Routing
T420-CX integrates a high performance packet switch, which allows
switching traffic from any of the input ports to any of the output
ports (wire-to-wire) and from any of the output ports to any of the
input ports (host-to-host).
Ordering info
Model: T420-CX
Physical interface: 10GBASE-CX4
Connector: CX4
Media: CX4 copper*
Accessories
CX4CABLE3M CX4 copper cable, 10GBASE-CX4, 3-meter
CX4CABLE15M CX4 copper cable, 10GBASE-CX4, 15-meter
*Supports active optical cables with distances up to 100 meters.
Complete and Flexible TCP Offload
The T4 has hundreds of programmable registers for protocol confi-
guration, RFCs, and offload control. The T420-CX can offload TCP
processing per connection, per-server, per-interface, and globally
and simultaneously tunnel traffic from non-offloaded connections to
the host processor for the native TCP/IP stack to process. The T420-
CX provides a flexible zero copy capability for regular TCP connec-
tions, requiring no changes to the sender, to deliver line rate per-
formance at minimal CPU utilization.
Specifications
Host Interface
PCI Express Gen2 x8
MSI-X, MSI and support for legacy pin interrupts
High Performance RDMA
Low latency and line rate bandwidth
Enhanced RDMA primitives
iWARP support on Linux OFED
Microsoft Network Direct support
UDP & Multicast Offload
UDP Sockets API
Low user-to-user latency
Multicast replication on ingress or egress
Virtualization
PCI-SIG SR-IOV
128 Virtual and 8 Physical functions
144 port virtual switch
EVB, VEPA, Flex10, VNTag
336 virtual MAC addresses
FCoE
Full HBA FCoE (Initiator or Target)
Open-FCoE Offload (Initiator)
CRC32 offload generation & verification
Ingress & Egress ACL (Access Control List)
iSCSI Acceleration
Full iSCSI initiator and target mode stack
CRC32 offload generation & verification
iSCSI proxy switching based on SCSI CDB
Full HBA offload
TCP/IP Full Offload
Full TCP implementation including IPv4 & IPv6
Microsoft Chimney support
Extensive RFC compliance, fully featured stack
Full TCP Proxy between any set of connections
VLAN support up to 4096 different VLAN IDs
Load balancing and Fail-over capabilities
Stateless Offloads
TCP/UDP checksum offload for IPv4 & IPv6
TSO, LSO, and GSO for IPv4 & IPv6
VLAN filtering, insertion & extraction
Line rate packet filtering and attack protection
Fine granularity time stamping (down to 4ns)
Ethernet Routing (packet header rewrite)
Packet Tracing and Packet Sniffing
Ethernet
IEEE 802.3ae (10 GbE)
IEEE 802.3z (1 GbE) compliant
IEEE 802.IP priority
IEEE 802.IQ VLAN tagging
IEEE 802.1Qbg EVB/VEPA
IEEE 802.1Qbh VNTag
IEEE 802.3x flow control
IEEE 802.3ad load-balancing and failover
Ether II and 802.3 encapsulated frames
Multiple MAC addresses per interface
Jumbo Frames up to 9.6Kbytes