Zyxel IES-1248 EE [259/544] Ip bridge overview

Zyxel IES-1248 EE [259/544] Ip bridge overview
IES-1248-51/51A/53 User’s Guide
259
CHAPTER 39
IP Bridge
This chapter explains how to set up the IP bridge function in the IES-1248.
39.1 IP Bridge Overview
The IP bridge function is designed for large-scale, flat, access networks, and it is ideal when
the network is based on Ethernet. When the IP bridge is enabled, the IES-1248 forwards
frames based on the destination IP address, instead of the destination MAC address, and it
replaces the source MAC address with its own MAC address.
Figure 131 IP Bridge: Traditional vs. IP-aware DSLAM
The IP-aware IES-1248 does not modify the IP packet header, but it uses the destination IP
address to modify the layer-2 header, in particular the source MAC address, destination MAC
address, and VLAN tag. As a result, the IES-1248 prevents the MAC addresses and VLAN ID
downstream of the IES-1248 (in other words, the subscribers’ MAC addresses and VLAN ID)
from propagating into the network upstream of the IES-1248, and vice versa.
Traditional
Forward by
destination MAC
IP Aware
Forward by
destination IP

Содержание

Скачать