Black Box LR1102A-T1/E1, LR1112A-T1/E1 Virtual LAN Tagging, Managing Traffic with Vlan Tagging

23

VIRTUAL LAN TAGGING

23.1 Managing Traffic with VLAN Tagging

Figure 41 Aggregation Using VLAN Tagging

Baltimore

Aggregation /IP

Services Router

To Internet

POP

Router T1

Local

Loop

Reston VA

DC	CT3
	NxT1

LR1104A

LR1114A

The illustration above shows two customers connected to an aggregation/IP services router using a Black Box LR1104A. All packets coming into the Black Box LR1104A 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 Black Box LR1104A to the VLAN-enabled POP router. The tags are removed in the reverse direction. Black Box’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 a Black Box product can be accomplished remotely (for example, at DC) after the T1 cable has been connected. Thus, deploying a technician to reconfigure the unit is not necessary.

By connecting the Black Box LR1104A using a VLAN switch, additional LR1104As and POP routers can be easily added. If additional LR1104As 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 LR1104A, in conjunction with Black Box’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 Black Box LR1104A proxies for the CPE routers after learning their IP addresses via link control protocol or inverse ARP. Routing between customer VLANs, firewall functions, and traffic management can be provided by the POP router sub-interfaces so there is only one location to monitor customer traffic.