Figure 42 shows a network topology that is used as an example in this section. In this example, your company's branch office is connected to its main branch using J-series Services Routers R0 and R1. You transmit data and voice traffic on two low-speed 1-Mbps serial links. To increase bandwidth, you configure MLPPP and join the two serial links se-1/0/0 and se-1/0/1 into a multilink bundle ls-0/0/0.0. Then you configure LFI and CoS on R0 and R1 to enable them to transmit voice packets ahead of data packets.
Figure 42: Configuring MLPPP and LFI on Serial Links
Configuring a multilink bundle on the two serial links increases the bandwidth by 70 percent from approximately 1 Mbps to 1.7 Mbps and prepends each packet with a multilink header as specified in the FRF.12 standard. To increase the bandwidth further, you can add up to 8 serial links to the bundle. In addition to a higher bandwidth, configuring the multilink bundle provides load balancing and redundancy. If one of the serial links fails, traffic continues to be transmitted on the other links without any interruption. In contrast, independent links require routing policies for load balancing and redundancy. Independent links also require IP addresses for each link as opposed to one IP address for the bundle. In the routing table, the multilink bundle is represented as a single interface.
This example uses MLPPP for providing multilink services. For information about configuring MLFR, see Configuring MLFR FRF.15 Bundles and Configuring MLFR FRF.16 Bundles.
You can use the LFI and CoS configurations provided in this example with MLFR FRF.15 and MLFR FRF.16 bundles, too. You can also use the same LFI and CoS configurations for other interfaces, such as on T1 or E1.
To configure MLPPP bundles and LFI on a Services Router, perform the following tasks: