Technical Product Specification

Intel® Server Boards S4600LH2/T2 TPS
Revision 2.0
72
6.10.2 IPMB Communication Interface
The IPMB communication interface uses the 100 KB/s version of an I
2
C bus as its physical medium. For more
information on I
2
C specifications, see The I
2
C Bus and How to Use It. The IPMB implementation in the BMC is
compliant with the IPMB v1.0, revision 1.0.
The BMC IPMB slave address is 20h.
The BMC both sends and receives IPMB messages over the IPMB interface. Non-IPMB messages received by
means of the IPMB interface are discarded.
Messages sent by the BMC can either be originated by the BMC, such as initialization agent operation, or by
another source. One example is KCS-IPMB bridging.
6.10.3 LAN Interface
The BMC implements both the IPMI 1.5 and IPMI 2.0 messaging models. These provide out-of-band local area
network (LAN) communication between the BMC and the network.
See the Intelligent Platform Management Interface Specification Second Generation v2.0 for details about the
IPMI-over-LAN protocol.
Run-time determination of LAN channel capabilities can be determined by both standard IPMI defined
mechanisms.
6.10.3.1
RMCP/ASF Messaging
The BMC supports RMCP ping discovery in which the BMC responds with a pong message to an RMCP/ASF
ping request. This is implemented per the Intelligent Platform Management Interface Specification Second
Generation v2.0.
6.10.3.2 BMC LAN Channels
The BMC supports three RMII/RGMII ports that can be used for communicating with Ethernet devices. Two
ports are used for communication with the on-board NICs and one is used for communication with an Ethernet
PHY located on an optional RMM4 add-in module.
6.10.3.2.1 Baseboard NICs
The on-board Ethernet controller provides support for a Network Controller Sideband Interface (NC-SI)
manageability interface. This provides a sideband high-speed connection for manageability traffic to the BMC
while still allowing for a simultaneous host access to the OS if desired.
The NC-SI is a DMTF industry standard protocol for the side band management LAN interface. This protocol
provides a fast multi-drop interface for management traffic.
The baseboard NIC(s) are connected to a single BMC RMII/RGMII port that is configured for RMII operation.
The NC-SI protocol is used for this connection and provides a 100 Mbps full-duplex multi-drop interface which
allows multiple NICs to be connected to the BMC. The physical layer is based upon RMII, however RMII is a
point-to-point bus whereas NC-SI allows 1 master and up to 4 slaves. The logical layer (configuration
commands) is incompatible with RMII.
The server board will provide support for a dedicated management channel that can be configured to be
hidden from the host and only used by the BMC. This mode of operation is configured via a BIOS setup option.