Redundant Ethernet signals from each blade server are routed through the enclosure backplane to
separate switches within the enclosure. However, specific switch port to server mapping varies depending
on which type of server blade is installed.
Supported technologies
Layer 2 switching
The switch uses Gigabit Layer 2 switching technology. Layer 2 refers to the Data Link layer of the OSI
model, which is concerned with moving data packets across a network by enforcing CSMA/CD. This
layer performs:
•
Ethernet packet framing
•
MAC addressing
•
Physical medium transmission error detection
•
Medium allocation (collision avoidance)
•
Contention resolution (collision handling)
Layer 2 switching technology allows the switch to look into data packets and redirect them based on the
destination MAC address. This reduces traffic congestion on the network because packets, instead of
being transmitted to all ports, are transmitted to the destination port only.
Layer 3 switching
In addition to Layer 2 features, the switch also supports Layer 3 switching. Layer 3 switching features
include:
•
IP forwarding
•
Static routing
•
Dynamic routing based on RIP V1/V2 or OSPF protocols
•
High availability VRRP
Layer 3 switching provides more power, flexibility, and security capabilities to network administrators.
Network traffic is managed much more efficiently and broadcast traffic between servers remains within
the enclosure. Security features provide added protection for switch configuration data, while packet
filtering helps secure and segment sensitive traffic or network access.
IEEE 802.1 Q-based VLAN
The switch provides support for a total of 1000 IEEE 802.1Q VLANs for server grouping and isolation. A
VLAN is a network segment configured according to a logical scheme rather than a physical layout.
VLANs are used to combine any collection of LAN segments into an autonomous user group that appears
as a single LAN.
VLANs also logically segment the physical network into different broadcast domains so that packets are
forwarded only between ports within the VLAN. This technology enhances performance by conserving
bandwidth and improves security by limiting traffic to specific domains.
Introduction 10