26 CHAPTER 1: GETTING STARTED
The Switch 5500 family supports the following services:
■Internet broadband access
■MAN (metropolitan area network), enterprise/campus networking
■Multicast service, multicast routing, and audio and video multicast service.
XRN Overview With the XRN (eXpandable Resilient Networking) feature, you can connect several
devices into a combined device and manage them as a single unit. The combined
device is called the Fabric, while the member devices are units. With XRN you can:
■Manage multiple devices in centralized manner, with low management cost.
■Extend the number of ports and switching capacity just by adding devices. You can
decide which equipment to purchase as needed, and better protect your existing
investment while upgrading the network.
■Provide backup between multiple devices to improve reliability and to eliminate
single points of failure.
Major Technologies XRN includes three technologies: distributed device management (DDM), distributed
link aggregation (DLA), and distributed resilient route (DRR).
■DDM: Users can treat the Fabric as a single device. They can manage the Fabric
through any port or IP address connected into the Fabric, and from any unit in the
fabric.
■DRR: The multiple units of a Fabric route and forward packets as a single unit, and
provide uniform VLAN interfaces, routing table and L3 forwarding table, so the
Fabric is regarded as a single Layer 3 switch. Failure of one of the units will not
affect routing protocol and data forwarding.
■DLA: Users can aggregate multiple ports of several different units in a Fabric into a
group, for centralized management within the Fabric. Trans-unit link aggregation
can bring convenient aggregation setting and effectively reduce single points of
failure.
The Switch 5500-SI supports basic XRN, that is DDM and DLA; the Switch 5500-EI
supports enhanced XRN, including DDM, DRR, and DLA.
Typical Networking
Topology
Typical XRN networking topology is as shown in Figure1. Switches of the same type
(that is, units) form a Fabric. As a core switch, the Fabric can be downlinked to
workgroup switches through several aggregation links, and uplinked to the server
group also through several aggregation links.
5500G-EI
PWR 48-Port AC-input,
DC-input
48 —44 10/100/1000
Mbps plus 4
10/100/1000 or SFP
1
5500G-EI
24-Port SFP AC-input,
DC-input
24 —20 10/100/1000
Mbps plus 4
10/100/1000 or SFP
1
Tabl e 3 Models in the Switch 5500 family (continued)
Model
Power
supply unit
(PSU)
Number of
service
ports
Number of 100
Mbps ports
Number of 1000
Mbps uplink
ports
Console
port