Table of Contents
Advertisement
4 Configuring Ethernet Services
4.2.5 Encapsulation and Mapping Protocol
To ensure that Ethernet frames can be transparently transmitted over the optical transmission
network, the Ethernet frames need to be encapsulated and mapped into VC containers at the
access point. The encapsulation and mapping protocols used by the Ethernet service board
include the high-level data link control (HDLC), link access procedure - SDH (LAPS), and
generic framing procedure (GFP).
4.2.6 Virtual Concatenation
The rate of the Ethernet service does not adapt to the rate of the standard VC container. Hence,
if you directly map the Ethernet service data into a standard VC container, there is a great waste
of the transmission bandwidth. To solve the problem, use the virtual concatenation technology
to concatenate many standard VC containers to a large VC container that adapts to the rate of
the Ethernet service.
4.2.7 Tag Attribute
When data frames are received on or transmitted from a port on an Ethernet board, the processing
mode of the data frames is determined by the tag attributes of the port.
4.2.8 Bridge
A bridge is a functional unit that is used to implement the interconnection between two or more
LANs.
4.2.1 Formats of Ethernet Frames
To implement the VLAN and QinQ functions, the IEEE 802.1q and IEEE 802.1ad protocols
define different formats of the Ethernet frames, which contain different VLAN information.
To implement the VLAN function, the IEEE 802.1q protocol defines the Ethernet frame format
that contains the VLAN information. Compared with the ordinary Ethernet frame, the frame
with the format defined by the IEEE 802.1q protocol is added with a four-byte header.
To implement VLAN mesting (QinQ), the IEEE 802.1ad protocol defines two VLAN tag types.
See
and the services on the supplier service side.
l
l
4-8
Figure
4-7. The VLAN tag types are defined to differentiate the services on the client side
The VLAN tag used on the client side is represented as C-VLAN, of which the frame format
is the same as the frame format defined by the IEEE 802.1q protocol.
The VLAN tag used on the supplier service side is represented as S-VLAN.
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
OptiX OSN 550 Multi-Service CPE Optical Transmission
System
Configuration Guide
Issue 02 (2011-06-30)
- Quick Links:
- Starting or Shutting down the U2000
Hide quick links:
Advertisement
Chapters
Table of Contents
