Monday, December 12, 2011

Data Center Interconnect: Layer 2 Extension Between Remote Data Centers

This document is intended to help network managers and systems managers understand the various solutions and recommendations that Cisco offers to geographically extend Layer 2 networks over multiple distant data centers. These offerings address the requirements of high performance and fast convergence.
This document also introduces the capabilities of the Cisco® Data Center Interconnect (DCI) solution. Please note that it does not address the requirements for SANs.
Initially, this document describes the types of connectivity (Layer 2, Layer 3, and storage) that can be established between remote data center locations, together with the services that a given enterprise can obtain from a service provider.
The discussion then focuses on LAN extension designs, analyzing some of the most relevant business factors requiring the deployment of a LAN extension, and providing a list of solution requirements.
The document concludes by describing some technical alternatives to provide LAN extension functions, including:

• Point-to-point or point-to-multipoint interconnection, using virtual switching system (VSS), virtual PortChannel (vPC), and optical technologies

• Point-to-point interconnection using Ethernet over Multiprotocol Label Switching (EoMPLS) natively (over an MPLS core) and over a Layer 3 IP core

• Point-to-multipoint interconnections, using virtual private LAN services (VPLS) or advanced VPLS (A-VPLS) natively (over an MPLS core) or over a Layer 3 IP core

For each technical alternative, specific platform support and positioning information is provided.