Allied Telesis Layer 3 Gigabit Ethernet Switch x600-24Ts/XP - Manual (Page 32)

Chapter 1: Overview
32
AT-LBM Module
The AT-LBM (Link Back) Module is installed in the expansion slot of the
x600-48Ts/XP switch. For an illustration, see Figure 8 on page 18. This
module provides a nonblocking switching configuration when there are
connections on the x600-48Ts/XP switch to all 44 copper ports and two
XFP ports.