Small wonder that service provisioning is fast becoming one of the hottest topics in optical networking – as evidenced at last week’s Supercomm trade show when four vendors made provisioning announcements: Tenor Networks Inc. http://www.tenornetworks.com, ONI Systems Corp. http://www.oni.com , Dynarc Inc. http://www.dynarc.com, and Alcatel SA http://www.alcatel.com.
A closer analysis of last week’s service provisioning announcements shows that beneath the interoperability demos, cutesy GUIs, and bravura sales pitches there are some razor wire-covered hurdles to surmount before these products deliver the goods.
The main problem is that there's no consensus on just how optical provisioning should be implemented. Right now, most vendors are using proprietary solutions -- including ones based on adaptations of MPLS (multi-protocol label switching)for optical networks. Work is under way to standardize this new version of MPLS, but it's no where near complete.
Experts also warn against making assumptions about touted MPLS support. "There's confusion about what it means to use MPLS," says Jim Lawrence, program director at Stratecast Partners http://www.stratecast.com, a consultancy. There will be key differences, he says, between MPLS that is used to provision IP networks in general and the version of MPLS that's being designed by groups like ODSI to work with special signaling protocols to configure optical connections. "The specs will use the same language, but there will be differences. English is spoken in the U.K. and the U.S., but there are fundamental differences in the way it is spoken" (see Crunch Time for Signaling Standard ).
Some even question how well MPLS will serve as an uber-protocol for provisioning. Vendors developing MPLS are "a bunch of lemmings," according to Stuart Barnes, director of engineering at Lilotron, a U.K. startup developing an all-optical switch. In his view, they are ignoring some harsh realities of carrier networks--such as the fact that incumbents have massive amounts of legacy gear already in place that can't be easily upgraded to support MPLS.
Others point out that there are some parts of carrier networks where MPLS may not be a fit at all. “MPLS will certainly be a big deal in the core. But it won’t be used all the way out to the metro edge of the network. That’s B.S!” exclaims Carl Russo, group vice president of the optical networking group at Cisco. Russo says MPLS will work well on backbone networks because they are built on a mesh topology -- the environment MPLS is designed for. Conversely, he says, MPLS is a poor fit for metro networks “…because they are physically built in rings, and will be for some time to come.”
Here’s the 411 on who announced what last week:
- Tenor Networks Inc. demo'd TEMPo, an element management system for its TN250G Optical Service Switch (see Tenor Builds A Network Toll Booth ). A key feature of TEMPo is a so-called OpticalExpress form, a GUI in which Tenor has cleverly adapted the format of a Federal Express order. Service providers fill out the form's "To" and "From" boxes in order to generate connections over the optical network between specific devices and locations. Other parts of the form are set up to cover scheduling, protection, and SLA options.
Here's how it's done: The TN250G automatically overlays any connection made by the switch (including packet-over-Sonet-based IP, ATM, frame relay, and TDM links over DWDM channels) with multi-protocol label switching (MPLS). Tenor's TEMPo software then uses MPLS facilities to monitor and control the specific functions of each link. The GUI provides the front end. Corba-based APIs (application program interfaces) can be used to funnel information from TEMPo to other OSSs (operations support systems), such as billing and workflow management programs used by carriers.
- ONI Systems Corp. ran a large-scale demo named Operation Interoptical. In it, ONI showed its Online series of DWDM-based optical transport switches working over an on-site network, specially constructed for the show. The demo linked ONI's gear to equipment from Amber Networks http://www.ambernetworks.com, Corvis Corp. http://www.corvis.com, Juniper Networks http://www.juniper.net, and Tellium http://www.tellium.com, as well as to SAN switches from Brocade Communications Systems http://www.brocade.com. Videos and interactive forms were shown to work on a network containing gear from all the participants.
Underlying the demo were ONI's APIs, which use SNMP, Corba, TL1, and other interfaces to take management and provisioning information from third-party equipment and software and incorporate it into ONI's XML-based management system for the Online switches. Underlying optical links are set up by the Online switches.
- Dynarc Inc.
showed its Dynarc 5116 router, which gives carriers the means
to control bandwidth provisioning in optical nets by using a proprietary
transmission scheme. The Dynarc router replaces ATM and Sonet links in
optical nets with a proprietary synchronous time-division multiplexing
protocol called Dynamic synchronous Transfer Mode (DTM). Carriers use
Dynarc's management GUI to set up, assign, and manipulate DTM channels
to meet customer-specified access rates and levels of service. This
approach, Dynarc says, gives carriers the means to fully control optical
bandwidth provisioning right at the router without having to struggle
with costly ATM and Sonet management interfaces.
- Alcatel SA previewed its 770 RCP (Routing Core Platform) terabit router, and told Light Reading that it intends to sell it as part of an integrated solution set that also includes its optical crossconnects and an overarching suite of management and service provisioning software. The software, code-named Optip, will allow long-distance carriers to slice up capacity in the core of the Internet and make money by selling it to smaller service providers, such as CLECs (see Alcatel Boxes Clever ).
All of the vendors say they'll support MPLS-based standards over time from groups such as the IETF, Optical Internetworking Forum (OIF), http://www.oiforum.com), and the Optical Domain Service Interconnect (ODSI) coalition.
And none of them are willing to wait and see what comes of these efforts before heading to market. They have good reason: MPLS-based provisioning standards are far from finished. Initial specs from the OIF and ODSI aren't expected until later this year, with prototypes following in 2001. There are questions about how the groups fashioning the specs will work together.
-- by Mary Jander, senior editor, and Stephen Saunders, US editor, Light Reading http://www.lightreading.com