Chapter 39: Vlan Tagging - Avaya 1000 Series Configuration Manual

Chapter 39: VLAN Tagging

Figure 43: Aggregation Using VLAN Tagging
The illustration above shows two customers connected to an aggregation/IP services router using a
SR3120. All packets coming into the SR3120 on the single T1 bundle are tagged with VLAN ID 5. All
packets coming across the 4 T1 bundle from DC are tagged with a VLAN tag of 10.
In this example, the VLAN tags are only relevant from the SR3120 to the VLAN-enabled POP router. The
tags are removed in the reverse direction. Avaya's IP multiplexing technology enables both remote
customers to operate as if they are directly connected to the POP router residing on a tagged VLAN. In
this scenario, the provider can offer HDLC, PPP, MLPPP, frame relay, and MFR connections. (The sample
configurations in this document assume Baltimore uses frame relay and DC uses MLPPP.) Upgrading
customer service by adding T1s to an Avaya product can be accomplished remotely (for example, at DC)
after the T1 cable is connected. Thus, deploying a technician to reconfigure the unit is not necessary.
By connecting the SR3120 using a VLAN switch, additional SR3120s and POP routers can be easily
added. If additional SR3120s are desired, the appropriate uplink from the VLAN switch is Gigabit Ethernet.
Redundancy for the POP routers can be provided using either the second fast Ethernet port on the
SR3120, in conjunction with Avaya's failover feature, or using HSRP/VRRP between the two routers. In
the latter case, a VLAN switch is required.
Special configuration is not required at the CPE for this application. At the POP, traffic from each bundle
or frame relay PVC is tagged and forwarded to a VLAN trunk port on the Ethernet interface. In the other
direction, the SR3120 proxies for the CPE routers after learning their IP addresses through link control
protocol or inverse ARP. Routing between customer VLANs, firewall functions, and traffic management
can be provided by the POP router subinterfaces so there is only one location to monitor customer traffic.
Network administrators have the option of not adding tagged VLAN interfaces to the VLAN management
group. This option allows network administrators to control access to the network by end users, who have
access through the tagged interface by default.
Avaya Secure Router 1000 Series Configuration Guide December 2010 251