Multiprotocol label switching makes for mainstream
Published: 09 Feb 2004 15:30 GMT
Who's using it
AT&T, British Telecom, BellSouth, Equant, Level 3, MCI and NTT Communications, among others, have already started using MPLS VPN services. Verizon said during its fourth-quarter conference call that it expects to launch its service in the second quarter of 2004. Sprint, which has traditionally been critical of MPLS, announced its new MPLS VPN service two weeks ago.
While newer carriers such as Equant and Level 3 have essentially built their network backbones using MPLS, many traditional carriers, such as AT&T and MCI, are still moving their disparate voice and data networks onto a fully converged MPLS infrastructure. Verizon -- the largest of the old-school Baby Bells -- said it will begin using a converged voice and data network with an IP/MPLS infrastructure in the fourth quarter of 2004. Even Sprint, which has always maintained that its pure IP backbone is much simpler than MPLS, is considering MPLS for convergence, although the company cautioned that it is still reviewing its options.
"There has been an evolution in MPLS over the past couple of years, and we are looking at it," said Barry Tishgart, director of product management at Sprint. "If we conclude that it provides higher performance at a lower unit cost, we will readily move in that direction. But it hasn't proven that yet."
Analysts said such caution over MPLS is justified, noting that the technology is still a work in progress. Although adoption is rising, there's still much work to be done. There is no such thing as a single MPLS "standard," and many standards defining different aspects of the technology are still evolving.
For example, MPLS works fine within a single carrier's network, but engineers and standards bodies still need to figure out how to interconnect carrier networks using MPLS. The challenge is to connect these networks so that quality end-to-end service can be guaranteed.
"One of the biggest issues for carriers deploying MPLS VPNs is geographic coverage," Burton Group's Lazar said. "No single carrier has a footprint in every corner of the world. It's important for customer traffic to be able to go from one carrier's network to another without too many problems."





