The MX Enhanced Switch Control Board (SCBE2-MX) serves the carrier Ethernet services router and carrier Ethernet transport markets that require higher-capacity traffic support, demanding greater interface density (slot and capacity scale) as well as improved services. The SCBE2-MX is supported on MX960, MX480, and MX240 routers.
The SCBE2-MX is installed vertically in the MX960 chassis and horizontally in the MX480 and MX240 chassis. The routing engine is installed directly into a slot on the SCBE2-MX (see Figure 1).
SCBE2-MX Weight and Dimensions
Maximum Power Requirements
SCBE2-MX (applies to MX240, MX480, and MX960)
185 W at 55° C
160 W at 40° C
155 W at 25° C
SCBE2-MX Cooling Requirements
For proper cooling, you must install MX-series high-capacity fan trays in the MX chassis. Additionally, for the MX960, you must install a high-capacity filter tray.
Centralized Stratum 3 Clock Module
Provides a central clocking module and a centralized clocking architecture that supports clock cleanup and distribution. The Stratum 3 clock module performs clock monitoring, filtering, and holdover at a centralized chassis location.
External Clocking Interface (
Allows BITS, GPS, or UTI clock source input to the centralized timing circuit. Also allows centralized timing to be output to BITS or GPS.
Cross-Coupling of Clocking Input
You can configure the system such that one SCBE2-MX supports a GPS clocking interface, and the other SCBE2-MX supports a BITS clocking interface. This requires an enhanced midplane:
Improved Fabric Performance
Provides improved fabric performance for high-capacity line cards using the third generation fabric XF2 chip (MPC4E, MPC5E, MPC2/3 NG, and MPC7E).
Software Control Plane Features
Supports Dynamic Multicast Replication (DMR), Graceful Routing Engine Switchover (GRES), Non-Stop Routing (NSR), and Non-Stop Bridging (NSB) to ensure Routing Engine failures do not impact transit traffic while the backup Routing Engine becomes the new master.
Provides up to 480 Gbps (non-redundant fabric configuration); 340 Gbps (redundant fabric configuration)
In-system removable Routing Engine
The in-system Routing Engine can support any new Routing Engine that conforms to the standard modular Routing Engine I/O interface and form factor.
Note: When a Routing Engine is not installed in the SCBE2-MX, you need to cover the empty slot with a blank panel.
The SCBE2-MX and associated Routing Engine assembly are hot-swappable and do not require downtime to replace. The system software provides a mechanism to shut down, or acquiesce the Routing Engine/SCBE2-MX. The system software also provides a method to reset or reboot the Routing Engine/SCBE2-MX. This support is provided via CLI commands, and various hardware support circuits.
Note: The Routing Engine must be brought offline prior to removal to avoid possible corruption of the hard drive.
With three SCBE2-MX’s installed, the MX960 router provides 2 + 1 redundancy. With two SCBE2-MX’s installed, the MX240 router and MX480 router provide 1 + 1 redundancy.
1000Base-T Ethernet Controller
Provides a 1 Gbps Ethernet link between the Routing Engines.
Allows you to upgrade programmable parts and reboot with “hitless” operation if the redundant SCBE2-MX’s are inserted in the system and are operational.
Indicate the status of the SCBE2-MX. See SCBE2-MX LEDs.
Two Ethernet ports, labeled
The RJ-45 external clock interface port, labeled
Three LEDs labeled
Table 1: SCBE2-MX LEDs
Fabric is in active mode.
SCBE2-MX operates in fabric-only mode.
SCBE2-MX operates in fabric or control-board mode.
SCBE2-MX is online.
SCBE2-MX has failed.
SCBE2-MX is offline.
Building-integrated timing supply (BITS) clocking interface is active.
BITS clocking interface has failed.
BITS clocking interface is offline.
Global positioning system (GPS) clocking interface is active.
GPS clocking interface has failed.
GPS clocking interface is offline.
Universal Timing Interface (UTI) clocking interface is active.
UTI clocking interface has failed.
UTI clocking interface is offline.
Port is enabled and link is established.
Port is disabled or no link is established.
SCBE2-MX Fabric Planes and Redundancy
For the MX960:
Each SCBE2-MX provides two switch fabric planes for packet forwarding among the MPCs in the MX960.
The MX960 chassis may contain up to three SCBE2-MX's Therefore, six fabric planes are available.
Three SCBE2-MX’s are required for 2 + 1 redundancy.
In redundant fabric mode, four fabric planes from the first two SCBE2-MX’s will be in Active mode, and two fabric planes from the third SCBE2-MX will be in Spare mode.
In a non-redundant fabric mode, all six fabric planes will be in Active mode to increase fabric bandwidth.
For the MX240 and MX480 routers:
Each SCBE2-MX provides four switch fabric planes for packet forwarding among the MPCs in the MX480 and MX240 chassis.
The MX480 and MX240 routers contain a maximum of two SCBE2-MX’s. Therefore, eight logical planes are available.
Two SCBE2-MX’s are required for 1 + 1 redundancy.
In redundant fabric mode, four fabric planes from the first SCBE2-MX will be in Active mode, and four fabric planes from the second SCBE2-MX will be in Spare mode.
In a non-redundant fabric mode, all eight fabric planes will be in Active mode to provide increased fabric bandwidth.
Each fabric ASIC is configured in virtual plane mode, where two virtual planes exist on one fabric ASIC.
SCBE2-MX Slot Locations in the MX Chassis
For the MX960:
You can install up to three SCBE2-MX’s in the MX960 router chassis.
SCBE2-MX’s are installed vertically into the front of the MX960 chassis in the slots labeled
2. If any slots are empty, you must install a blank panel.
The two SCBE2-MX’s residing in slot 6 and slot 7 of the MX960 chassis provide both control and switch fabric features, while the third SCBE2-MX residing in slot 8 of the chassis (hybrid slot) will only do fabric functions.
For the MX480 and MX240 routers:
You can install either one or two SCBE2-MX’s in the MX480 and MX240 router chassis.
SCBE2-MX’s are installed horizontally into the front of the MX480 and MX240 chassis in the slots labeled 0 and 1. If any slots are empty, you must install a blank panel.
SCBE2-MX Interoperability with Existing Hardware
SCBE2-MX Operating Mode
Enhanced IP/Enhanced Ethernet Mode Only
MPC7 (480 Gbps)
MPC8 (960 Gbps)
MPC9 (1.6 Tbps)
RE-S-1800 (all variants)
RE-S-X6 (all variants)
Upgrading to the SCBE2-MX
Here’s the procedures for upgrading your MX960, MX480, or MX240 router to use the SCBE2-MX: