Amer Networks E5Web GUI - Manual (Page 289)

Figure 4.8. Virtual Routing
When the administrator configures this in cOS Core, interface If1 is made a member of routing
table pbr1 but not pbr2. In other words, If1 is explicitly associated with pbr1. Conversely, interface
If2 is made a member of pbr2 but not pbr1. It is this interface membership which determines
which routing table is used and this keeps the two sets of traffic totally separated.
Tip: Creating dedicated routing tables is best
In this example, the main routing table could have been used as one of the two routing
tables. However, it is usually better and clearer to instead create new, dedicated routing
tables with appropriate names for each separated portion of data traffic.
Reusing Private IP Addresses
An advantage of using separate routing tables on different interfaces is that internal, private IP
address ranges can be reused on different virtual systems. For example, Department A and
Department B could both use the internal network 192.168.0.0/24.
Since route lookup is done in completely separate routing tables, there are no conflicts.
VPN Tunnels are Interfaces
VPN tunnels are also considered to be interfaces in cOS Core and can therefore also be
associated with their own routing tables just as physical interfaces can.
This means that VPN tunnels can be logically separated from each other within cOS Core.
Using Loopback Interfaces
In this simple example, loopback interfaces were not used since there is no requirement for
Chapter 4: Routing
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