Cisco 10000 - Manual (Page 47)

1-15
Cisco 10000 Series Router Software Configuration Guide
OL-2226-23
Chapter 1 Broadband Aggregation and Leased-Line Overview
New Features, Enhancements, and Changes
Figure 1-19 Single Ingress and Two Egress PE Load Balancing
You can set load balancing to work per-destination or per-packet. For per-destination load balancing, the
packet arrives at the core router 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.
Per-packet load balancing allows data traffic to be evenly distributed in an IP network over multiple equal-cost
connections. Per-packet load balancing uses round-robin techniques to select the output path without basing
the choice on the packet content.
Multiple Ingress and Multiple Egress Provider Edge Applications
Figure 1-20 shows multiple IGP paths from PE to PE for iBGP paths into the PE2 router. The theoretical
load balance is eight IGP paths multiplied by eight iBGP paths for a total of 64 possible unique paths.
The Cisco 10000 series router supports eight unique paths. The
“Single Ingress and Single Egress
Provider Edge Applications” section on page 1-14 describes the path selection for this model.
Figure 1-20 Multiple Ingress and Multiple Egress PE Load Balancing
New Features, Enhancements, and Changes
The following sections describe features that are new, enhanced, or changed for the specified Cisco IOS
software releases:
• New Features in Cisco IOS Release 12.2(33)XNE3, page 1-16
• New Features in Cisco IOS Release 12.2(33)SB3, page 1-16
P1
P2
CE2
158659
Dest prefix
10.1.1.1
PE1
PE3
PE1 CE1
P2
P1
P3
PE1
CE1
158660
Dest prefix
10.1.1.1
20.1.1.1
PE2
PE3
CE2