User`s manual

Chapter 1 Overview
7
 Bridge and Spanning Tree Protocol (STP)
When the MUXpro is equipped with 6 LAN ports (4 ports with Ethernet switch and
2 transparent ports), the total number of virtually concatenated groups supported
by the MUXpro is 6.
1.2.3 Handling the Ethernet Traffic
The Ethernet traffic is encapsulated for transmission via SDH network using one of
the following link-layer protocols:
 Generic Framing Procedure (GFP) in accordance with ITU-T Rec. G.7041,
framed mode, including support for GFP multiplexing
 Link Access Procedure for SDH (LAPS) protocols – per ITU-T Rec. X.85/X.86
draft recommendations.
The six traffic groups from the Ethernet switch are mapped into SDH containers
using virtually concatenated groups. Mapping is flexible, and enables using any
combination of virtually concatenated groups.
Unlike the traffic from the Ethernet switch, which can be switched along with
predefined VLAN groups to various virtually concatenated VCs, the Ethernet traffic
from the two transparent ports are always connected to a fixed group (port 5 to
group 5, etc.).
The fraction of network-linked bandwidth allocated to each virtually concatenated
group can be configured. Besides, LCAS can be used on any virtually
concatenated group with more than one VC to increase or decrease the capability
in accordance with the diverse application requirements, and remove component
VCs that failed.
1.2.4 E1 Ports
The E1 ports of the MUXpro have selectable balanced or unbalanced copper
interfaces per ITU-T Rec. G.703, with support for short-haul applications. The
ports support unframed E1 streams in compliance with ITU-T Rec. G.703. Each
E1 port provides two indications: loss of signal (LOS) and AIS.
The E1 multiplex structure is VC-12, TU-12, TUG-2, TUG-3, or AU-4 where each
E1 port can be placed in any VC-12 inside the STM-1 bandwidth.