Features Of Dual Home Network Architecture - Cisco ASR 9000 Series System Configuration Manual

Features of Dual Home Network Architecture

Table 2: Supported Satellite Network Encapsulation
Topology Type
Hub and Spoke
Layer 2 Fabric
Simple Ring
Features of Dual Home Network Architecture
These are some of the enhanced features offered by the dual home network architecture:
• Shared control for chassis functionality — Chassis control functionality which includes software
• Active/Standby determination — Active/Standby determination is controlled by the hosts. They
Cisco ASR 9000 Series Aggregation Services Router nV System Configuration Guide, Release 5.3.x
12
SDAC Discovery Protocol Packets
Untagged LLC SNAP
Single tagged LLC SNAP
Untagged LLC SNAP
upgrade, chassis reload, and environment monitoring is completely shared by all hosts connected to the
Satellite. Both the hosts get equal access to the information, and have full control of any available actions.
As a result, a disruptive change initiated by one host, such as an upgrade is noticed by the other host as
well. This means that here is no segregation of the chassis functionality and provides multiple views to
the same information.
exchange the pertinent information through ORBIT protocol, which includes electing a priority selection
algorithm to use. This algorithm determines the factors that are taken into account when calculating
priority information. The hosts then each send a single numerical priority value to the Satellite. The
Satellite only picks the lowest-host priority value, and forwards data to that host. If the host-priority is
same and a simple ring topology is used, the lower hop count is used. If the hop count is same, the lower
chassis MAC address is used for picking the active host. Independently, the hosts make the same
determination, and the traffic flows bi-directionally between the Active host and the Satellite. The hosts
take a number of parameters into account when calculating the priority value, including the user-configured
priority, the hop-count (path length) from the host to the Satellite, and a tie-break of the chassis MAC
for each host.
Cisco IOS XR Software uses these parameters to calculate the priority, where each item is more important
than any of the subsequent ones. This means that the subsequent parameters are only taken into account,
if the higher-priority items are identical across the two hosts.
◦Connectivity – Indicates whether the Host and Satellite can currently exchange data.
◦PE isolation – Indicates that if the PE is isolated, then it defers to the other host.
◦Minimum Links – Indicates that if the number of active links is less than the configured value in
bundled ICL, then it defers to the other host. For more information, see
Links for Dual Home Topology, on page
◦Configured Priority – This is as early as possible to allow the greatest flexibility for the operator.
Configuring the Satellite Network Virtualization (nV) System
SDAC Control Protocol Packets
Untagged TCP
Single tagged TCP
Untagged TCP
13.
Data Packets
802.1ad + customer payload
802.1ah + customer payload
Note
Supports both 802.1ad and 802.1q as outer
tag. Using 802.1q outer tag is a non-standard
way of 802.1ah Encapsulation.
802.1ah + customer payload
Note
Supports both 802.1ad and 802.1q as outer
tag. Using 802.1q outer tag is a non-standard
way of 802.1ah Encapsulation.
Soft Minimum Active