User guide

EDA System Design
96 1/1551-HSC 901 35/3 Uen C 2005-12-02
These requirements are the main input when dimensioning the aggregation
network (the number of switches and the bandwidth required to connect
them).
10.3 EDA Scenario Examples
The following examples of EDA scenarios are divided primarily according to
the method used for service selection:
1. No service selection.
2. Using a BRAS.
3. Using a VLAN per service or super VLAN.
4. Using IP sub-netting combined with Forced Forwarding.
5. LAN-to-LAN transparency
10.3.1 No Service Selection
In some access scenarios it may not be required or relevant to use any
form of service selection. The Access Domain merely provides unrestricted
Ethernet access to one or more Edge Nodes (IP Routers and/or Voice
Gateways). There is no authentication or authorization of subscribers. An
example network is depicted in Figure 60 on page 97.
This scenario provides layer-2 visibility. This implies that peer-to-peer
connections between EDA subscribers within the same IP subnet are
possible. The advantages of such connections are a better usage of
network resources and lower delay.
The drawbacks are potential security risks caused by the accessibility on
layer 2.
While layer-2 visibility between subscribers is an implicit feature of this
scenario, it is possible to protect the Access Domain equipment by using
one or both of the following security mechanisms:
1. Traffic filtering in the IP DSLAM. Relevant options are:
a IP/MAC address filtering
b Broadcast filtering