Chapter 20. Edge Virtual Bridging - Lenovo Flex System Fabric CN4093 Application Manual

Chapter 20. Edge Virtual Bridging

© Copyright Lenovo 2015
The 802.1Qbg/Edge Virtual Bridging (EVB) is an emerging IEEE standard for
allowing networks to become virtual machine (VM)‐aware. EVB bridges the gap
between physical and virtual network resources. The IEEE 802.1Qbg simplifies
network management by providing a standards‐based protocol that defines how
virtual Ethernet bridges exchange configuration information. In EVB
environments, virtual NIC (vNIC) configuration information is available to EVB
devices. This information is generally not available to an 802.1Q bridge.
Lenovo N/OS EVB features are compliant with the IEEE 802.1Qbg Authors Group
Draft 0.2. For a list of documents on this feature, see:
http://www.ieee802.org/1/pages/802.1bg.html.
Lenovo N/OS implementation of EVB supports the following protocols:
 Virtual Ethernet Bridging (VEB) and Virtual Ethernet Port Aggregator (VEPA):
VEB and VEPA are mechanisms for switching between VMs on the same
hypervisor. VEB enables switching with the server, either in the software
(vSwitch), or in the hardware (using single root I/O virtualization capable NICs).
VEPA requires the edge switch to support "Reflective Relay"— an operation
where the switch forwards a frame back to the port on which it arrived if the
destination MAC address is on the same port.
 Edge Control Protocol (ECP): ECP is a transport protocol that operates between
two peers over an IEEE 802 LAN. ECP provides reliable, in‐order delivery of
ULP (Upper Layer Protocol) PDUs (Protocol Data Units).
 Virtual Station Interface (VSI) Discovery and Configuration Protocol (VDP):
VDP allows hypervisors to advertise VSIs to the physical network. This protocol
also allows centralized configuration of network policies that will persist with
the VM, independent of its location.
EVB Type‐Length‐Value (TLV): EVB TLV is a component of Link Layer

Discovery protocol (LLDP)‐based TLV used to discover and configure VEPA,
ECP, and VDP.
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