* How MPLS applies to data centers
Architects of next-generation data centers need to think seriously about how Multi-protocol Label Switching fits into their plans. That may seem counterintuitive: MPLS is a WAN technology, which doesn’t directly apply to data centers. But MPLS-based services can deliver significant value for certain types of data center architectures.
There are four key ways in which MPLS-based WAN services can affect data center architectures:
First, MPLS can provide load balancing across multiple data centers. One of the benefits of MPLS is cost-effective, highly reliable, any-to-any connectivity. Older technologies such as ATM and frame relay are priced by the (virtual) circuit, which encourages designing WANs with the fewest possible circuits. Such designs are typically hub-and-spoke, with remote sites connecting to central sites (typically data centers). This works well in a scenario in which a cluster of regional sites is served by dedicated data centers. But as enterprises consolidate data centers, there’s an increasing chance that remote sites will need to access more than one data center. MPLS-based services provide a cost-effective way for remote sites to connect to multiple data centers – and if the data centers contain redundant applications or data, to load-balance between them.
Second, there’s the emergence of next-generation computing technologies such as grid computing, peer-to-peer and Web services. As noted, MPLS-based services excel at providing high-performance any-to-any connectivity. Web services and peer-to-peer networking generate any-to-any traffic patterns; grid computing does the same. Moreover, grid, Web services, and peer-to-peer applications often require QoS capabilities. Organizations seeking to deploy these technologies across a WAN should definitely look into MPLS.
Companies moving to IP PBXs may also find MPLS-based services worthwhile. MPLS’s QoS capabilities are tailor-made for voice – and it’s generally a good idea to locate PBXs in highly available, fully redundant environments such as data centers.
Finally, one of the major challenges of older WAN architectures is how to provide cost-effective redundant connectivity to backup sites. WAN services that charge by the circuit create scenarios in which enterprises must choose between high reliability and essentially paying for a duplicate backup WAN. Capabilities such as switched virtual circuits can mitigate the cost, but increase operational complexity. Enterprises need to configure SVCs to switch automatically to the back-up sites in event of a failure, and test their configurations regularly. Again, MPLS’s any-to-any capability can help.
MPLS-based services aren’t for everyone, but data center managers engaged in consolidation, looking to load-balance across multiple data centers, or with requirements for VoIP or high availability should definitely consider them.
