Combined Broadband And Leased-Line Applications; Load Balancing Architecture Models; Ip And Mpls Applications - Cisco 10000-2P2-2DC Software Configuration Manual

Chapter 1 Broadband Aggregation and Leased-Line Overview

Combined Broadband and Leased-Line Applications

The demarcation between leased-line and broadband applications has become less clear over the past few
years. DSL circuits are competing in the traditional leased-line space, with many service providers
offering Internet and VPN services over these lower-cost alternatives to dedicated TDM. The role of the
leased-line aggregator has expanded to include the termination of many traditional broadband interfaces
and encapsulations. Combining leased-line and business-class DSL access is one option that many
providers are introducing to reduce costs and consolidate the number of edge products.
Figure 1-16
Figure 1-16
Broadband
protocols
Ethernet
Lease- line
protocols

Load Balancing Architecture Models

This section describes how the Cisco 10000 series router load balances traffic in various network
topologies. The scenarios apply to a Cisco 10000 series router with a PRE2.

IP and MPLS Applications

Figure 1-17
MPLS VPN routes. There are multiple outgoing paths from the R1 router to the R2 router. Load
balancing is achieved by populating multiple paths in the PXF. On a Cisco 10000 series router, load
balancing is supported on a maximum of eight unique paths.
Figure 1-17
You can set load balancing to work per-destination or per-packet. For per-destination load balancing, the
packet arrives at R1 and the hash value is computed based on the source IP address, destination IP
address, and router ID. The PXF has a proprietary algorithm to select a path based on the number of total
paths available.
OL-2226-23
shows an example of combined broadband and leased-line architecture.
Combined Broadband and Leased-Line Architecture
Cisco 10000
series
shows a simple network topology that uses IP or basic MPLS forwarding. It does not include
IP and MPLS Load Balancing
P1
R1
P2
VPN
Internet
access
R2
Cisco 10000 Series Router Software Configuration Guide
Load Balancing Architecture Models
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