
July 1998 Volume 16.7
Netwatcher (ISSN 0890-5800) is a monthly publication of CIMI Corporation. Subscription information is available here . Copyright © 1998, CIMI Corporation. All rights reserved. No publication or reproduction of this document is permitted without the express written consent of CIMI Corporation.
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Management Briefing |
The proposed acquisition of TCI by AT&T and the merger of Bell Atlantic and GTE are clearly major events in the telecommunications field. One might rightfully wonder if theres a trend underway here, and if so what it might mean.
In past issues, weve looked at the shake-out in the equipment vendor space, a shake-out arising from changes in the nature of enterprise network-building. Its time to do the same for the carrier services space, and to do that we have to look back into the past.
The Carrier Regulatory Trends The carrier service market has been shaped from the first by the regulatory process. Since communications is a "community" function valued because of who can be reached with it, it was critical to insure that competition didnt fragment the user base into small enclaves whose populations would not have been large enough to provide a basis for useful communications. The concept of a regulated national monopoly was an effective solution to the problem, guaranteeing a carrier a market and encouraging investment in equipment. It was, in fact, the model adopted worldwide to promote the growth of telephony.In the early 1970s, it became clear that competition in at least the long-distance area could promote savings for buyers. MCI and Sprint, among others, provided that competition, but these new competitors believed that AT&Ts position as the local exchange carrier with the largest market by far gave them a preferential position in the competition. The result was the voluntary break-up of AT&T in a complex set of steps administered by the Federal judiciary, and often called the "Modified Final Judgement" or MFJ. This created the seven Regional Bell Operating Companies, and opened full competition in the long-distance area, with regulated monopolies still controlling the local access market.
Telecom 96 changed that, providing the RBOCs with the incentive (release from offering long-distance calls in their regions) to open their local market to competition. PUCs in various states moved with varying degrees of aggression to mandate local competition, but none of the RBOCs have yet filed papers with the FCC proving adequate compliance with the 14 competitive requirements of the Act, and so the Acts mandated reforms are not yet effective.
Carriers Respond in the Boardroom What has happened instead is a change in the business makeup of the carrier market, as players position for the enforcement of the Act. Bell Atlantic and Nynex merged, as did SBC and PacBell. SBC bought SNET and is seeking consent to acquire Ameritech, and Bell Atlantic wants GTE. AT&T tried to link up with SBC, and now wants to acquire cable giant TCI.All this maneuvering is aimed at the reality of the 21st-century market, which will pit every carrier against every other one. In such a world, size counts, and so it is likely that there will be continued M&A activity until none of the RBOCs or IXCs that existed at the time of the MFJ will remain "unmarried".
The goad behind this is the principle of one-stop shopping. A carrier with a broad service repertoire is more attractive to buyers because that carrier can serve all the buyers needs. Such a carrier can also avoid competitive pressure by keeping other players out of their key accountssomething that couldnt be done if these accounts needed a service the primary carrier couldnt offer. Broad service offerings alwo provide a better base for discounting, so its clear that bigger is better.
There are also other issues on the table. The RBOCs, at the end of the compliance process, will essentially be full-service carriers in their region, and able to expand into any other region they choose. They need long-distance capability to insure they can capitalize on what the Act lets them doenter the IXC space. The IXCs, on the other hand, have no region where they are incumbent in the local exchange market. Thus, the balance of power is shifted by the Act from the IXC to the RBOCsespecially the big ones.
The first effect of this second issue of service breadth was the validation of what weve called "special service interexchange carriers (SSIXCs), like Quest, Williams, and Level 3. The motivation here, we believe was to offer the RBOCs a long-distance partner who was securely not in the local exchange business, preparing for the possibility that the traditional IXCs would enter the local market to level their playing field with the RBOCs. The SSIXCs have no local infrastructure or marketing, and need LEC channels to connect to their customers and sell their services. So far, lacking enforcement of the Act, these guys have been having a bit of a tough time.
The second effect of this issue was the AT&T/TCI announcement. AT&T needs to establish their own link to their customer base. If the FCC and PUCs had set the wholesale rate of local service low enough, AT&T would probably have passed local access through to the customer at cost in order to encourage users to up their access bandwidth and enable sale of more nodal long-distance services. Since the wholesale margins on local access were limited to about 23%, AT&T needed something more, and TCI provides itmaybe.
Cable access for telephony is a tough call, considering that the cable TV provider is the second-most-unreliable (after the Internet provider) carrier in the buyers experience. It may well be that AT&T hopes to scare the RBOCs into lowering access charges, in which case it might never provide anything over the TCI plant except data services. Only time will tell here.
Speaking of time telling things, were waiting for the dice to stop rolling on the question of what happens to BellSouth and US West in the RBOC space, and MCI/WC and Sprint in the IXC space. None of these firms are viable in stand-alone mode in a fully competitive market, and the number of possible match-ups are shrinking.
Who Might Marry Whom We believe that both BellSouth and US West are courting IXC partnersMCI or Sprint. Such an acquisition, however, would require the RBOC have complied with the Telecom Act, and we also believe the players are holding that compliance off as long as possible. Since Congress reviews the progress of reform next year, we expect compliance in early 1999, and that would time the match-up of both US West and BellSouth. If we had to bet on partners now (which is really risky), wed link Sprint with US West and MCI/WC with BellSouth.The next group of carriers to begin the M&A dance will be the second-tier long-distance players and second-tier national frame relay players. These carriers are also non-viable in a highly competitive market because they cant secure the economy of scale in their infrastructure equal to that of the major players, and profit margins will thin out with increased competition. The hope of all these folks is that an RBOC will buy them, but we believe that the only ones with a shot will be those with facilities. The SSIXCs like Quest may want to be bought at this point, but some others (Williams, for example) may go on a shopping spree themselves to build their mass and hope to compete on a larger scale.
VPN services may be the key to this stage of market activity, because only data VPNs can introduce enough new revenue and profit into the picture to permit wholesale capital infrastructure spending. The players who get a big VPN boost will be able to build up their networks, enabling them to either go it on their own if they like, or strike an attractive deal if theyre so inclined.
ISPs will follow as the last phase of this market. Media hype notwithstanding, the Internet is a revenue pimple in todays market, and nobody smart is going to try to secure it when the bigger sectors are still up for grabs. By about 2001 or 2002, however, the VPN market will have grown enough to encourage more traditional players to buy a larger position in the public IP space. This will send all the merged megaplayers to the ISP supermarket, and the result will be the consolidation of the Internet space with the traditional voice space. This will be done by about 2005.
Do I Need To Do Anything? Users shouldnt worry about service levels or stability of their carriers, unless they have selected somebody really sleazy. All of the major players will either live independently or as a valuable part of a merged unit.The ones to worry about will be the smaller guys, who will be under considerable pressure and may skimp on network cost in order to stay profitable. This would result in lower levels of service or more outages.
Users should be wary of signing long-term deals, though. The best negotiating times will be around the turn of the millenium, so dont get locked into a long contract at that point. Most IXCs today are trying to give buyers "incremental" new deals annually on the condition that they extend their service contract for three years. This is a play to control the customer during the period of greatest competition, so if youre hoping to shop for a deal you should expect to give up a few percent now to keep your options opened.
It also may be useful to watch the technology choices that carriers make. There are rumors (we think unfounded) that AT&T is going to go to a complete IP-based network, for example. If you dont think IP is the right technology for your voice service, you may want to be sure that you arent committed to AT&T (or any player with similar plans) through the period of conversion. At the least, give yourself a "technology change" or "service level experience" clause that lets you bow out of the contract if you dont like how things are going.
One thing to keep in mind about the carrier space is the dependence on regulatory policy that we cited at the opening of this section. Regulations are government, and government is politics. Anything can happen.
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In the Know |
Most carrier relationships today start with an order and not with technology. The administrative infrastructure of the carrier world is not well known among users, even though every phone call and every service order consumes it.
Operations Support Systems, or OSSs, are the support foundation of voice telephony, and also of traditional data services based on leased lines. For some time, carriers have been wrestling with the question of how frame relay services, for example, would interwork with these OSSs. Now that data VPNs are on the horizon, it may well be that work is already obsolete, because VPNs mandate a whole different set of features.
Whats in a "VPNOSS", as we might call these new systems to support data VPNs? Is the VPNOSS a replacement for, an adjunct to, or what, with respect to the current OSSs? Are there key players emerging in the VPNOSS space? These are the issues well consider in this section.
Whats a VPNOSS, Anyway?An OSS provides carriers with order support, trunk and circuit inventory and management, trouble-ticket handling, and billing. However different VPNs may be from traditional services, it is clear that all of these functions wouldnt need to be redone from scratch to form a VPNOSS. In fact, it is certain that carriers would want to reuse large portions of their existing systemsif for no other reason, to protect skills and practices developed through years of use.
VPNOSSs might be expected to interact with OSSs on a sector-dependent basis, as follows:
From this, we can draw a picture of a VPNOSS. It is a new high-level provisioning and order entry system for VPN services that will be available to service order processors in a carrier center. The VPNOSS will facilitate the gathering of service parameters, and will then provide a means of provisioning the requested service onto the network, making necessary changes in resource inventories. Problem analysis and management elements linked to the shared-resource VPN infrastructure will feed the current problem tracking software, and new billable event journaling elements will provide input to a slightly modified billing system.
A logical question to ask here would be how this structure will be formulated into a product. However logical the question may be, its one thats hard to answer at this point. The problem is that the evolution to a VPNOSS will be influenced by a variety of forces, and its not yet clear how those forces will balance over the next five yearsthe critical period for VPNOSS evolution.
Whos Pushing VPNOSSs?It would be surprising if the first factor that determined the direction of VPNOSSs wasnt the direction of VPNs, and happily VPN trends are the primary issue. Today, what buyers would call a "VPN" is most likely to be a frame relay or ATM network and associated access equipment, perhaps with some carrier management thrown in. This early VPN structure has its own "VPNOSS" in the management software of the infrastructure vendor.
Frame relay and ATM network management systems provide basic VPNOSS support in the areas of provisioning and problem management. This limitation of scope is not unreasonable given the fact that these services are sold primarily in the form of PVCs, and are subject to relatively long service contracts. In effect, the users network is one-off provisioned using a standard management console. The service order function consists of recording the requirements, which are passed in memo form to a specialist who then makes the necessary network changes.
In the problem management area, the virtual circuit nature of ATM or frame relay allows reasonable (but not complete) association of network problems to users, and trouble ticket software is generally offered for problem management.
Billing is handled by creating a recurring monthly contract charge for the service based on the individual pricing of the service elements. Because this is a contract charge, there is no need to meter usage or record special service events.
What this has done is effectively build a completely parallel VPNOSS, one that has no real integration with the standard OSS structure of the carrier. As we noted in the opening comments of this section, this has already resulted in some carrier pressure to create more efficient linkages between the management platforms of frame/cell networks and the OSSs. Thus, the carriers are pushing for some improvement.
The equipment vendors are also pushing, but for more infrastructure in the form of a network to provide for IP VPNs. These VPNs would be offering a connectionless service rather than virtual circuits, and would involve more OSI layers. Both these factors could be expected to make provisioning the service more complex, both in terms of taking the orders and in terms of managing the resources that individual VPNs can consume.
In truth, an IP VPN changes the picture of VPN provisioning fairly radically. Radical change, however, is not the friend of a vendor market segment like network management thats been a loss leader for a decade or more. Thus, current equipment vendors have tended to attack the problem of supporting IP VPNs using their basic network management offering. Both Cisco and Ascend have recently announced new management features targeting the VPN market, and both have made these features extensions of their management architecture. While both vendors would certainly like the market to view their new offerings as completely new, they are in fact largely based on previous management product elements.
There are other potential players interested in the VPNOSS space. Network management vendors like Micromuse who focus on the fault/alarm correlation and management process may find the fault interpretation aspects of VPN requirements a launch point for their products into the VPNOSS space. Multivendor provisioning vendors like Syndesis could jump off from the VPN requirement to support services across a variety of vendors equipment.
What were saying is that the shape of a VPNOSS will probably depend on what market forces gain ascendancy over the next year or so. If VPNs develop relatively slowly, we would expect the infrastructure vendors to retain more control over the evolution. If the opportunity develops quickly, the pressure to have a good solution in the VPNOSS space would tend to empower newer players.
Now, What a VPNOSS Might Look LikeAs we would see it, the core of a VPNOSS would be the same no matter what kind of player ends up controlling evolution. Virtual network services need to be made concrete in order to be ordered and provisioned, so we would expect that all VPNOSSs would be built around a visualizer element that would create an icon or icons that could be said to represent a given VPN. The customer service rep at the carrier and the buyers representative would collaborate to create this VPN image, using interactive tools.
Once the image has been created, a VPNOSS would have to forward the image to a provisioning process to determine if the network infrastructure could support the resources required for the VPN. If the resources were not available, the VPN buyer would have to be contacted (assuming that this wasnt done in real time) and some resolution to the problems discussed. If the resources were available, the networks resource inventory would have to be reduced by the requirements for the VPN (even if it were to be made effective later, to be sure that resources were available at the time the VPN was turned on).
The provisioning process is the first place we might see some differences in structure based on the direction the VPNOSS vendor happened to take. An infrastructure vendor might elect to use a link to their own management system to provide the resource inventory and the provisioning interface combined. Thus, to these vendors the VPNOSS is an overlay to their normal management system. Most of the features of provisioning would reside in that management system.
This overlay approach also demands an accommodation to the multi-vendor nature of networks, so equipment players in the VPNOSS space are likely to have an interface to other vendors management platforms as well. This would make the VPNOSS a shell around whatever EMSs were in the network.
Vendors who are not players in the equipment space would probably not elect to cede as much functionality to the management system, since these vendors would have to rely on management features of various players. Instead, they would be likely to create sophisticated network map and inventory systems to serve as the basis for the provisioning process, and create specialized software to thread routes for VPNs based on service requirements. This would make them less dependent on the features of equipment EMSs, but since it is not possible to provision frame/cell products based on standard MIBs, some specialized code would be required for each vendor.
The same network image that guides provisioning would have to be used in problem analysis, for two purposes.
First, the resource commitment of the infrastructure to support this particular VPN would have to be recorded with the image so a problem in the network could be correlated to the VPNs it impacts. The way this would work would vary depending on what kind of VPN was involved (virtual circuit or connectionless) and what strategy was used to actually commit resources to it.
Second, the VPN image would form the repository for status data on the VPN, and this would be the basis for a customer display of the VPNa network icon in the customers management system. Problem tracking would have to work off this image, at least where problem tracking was customer-specific. We would assume that the trouble-tracking system would start with "real" hardware problems and generate VPN-specific trouble entries based on the image of the VPN. Customer complaints would have to follow the opposite routestart with a VPN trouble ticket and correlate that and other reports with the network to deduce where the real fault could be found, then generate a hardware ticket on it.
The billing aspect of the VPNOSS may be the most difficult. VPN images could be used to drive a software process to poll nodes and read relevant statistics, but this would impose an operating load on the network. We expect that the VPN players will eventually recognize the virtue of a Bellcore concept called "originating node journaling", where the access device linking the buyer with the VPN at each site is responsible for collecting the data needed to journal the events for billing.
This could have interesting impacts on the role of Class 5 switches. If a large portion of the line population in a given CO were to be VPN-equipped, adding data VPN capability to Class 5s through the use of an xDSL data card that pulled the data off onto a parallel LAN would be practical. In this situation, the data card would feed its data around the Class 5 itself, but journaling events could be funneled through the Class 5 into the billing system.
The originating-node concept plays well with VPNOSS promoters from all camps, because there are really no incumbent VPN edge players. Buyers dont associate VPN access with routers or FRADs in any determined sense, so incumbent equipment vendors dont have a lock on the space. With new vendors as valid as old, the software companies targeting the VPNOSS space have plenty of partnership opportunities.
There may be some special handling required on the billing side itself, depending on just what factors are used to develop the charges for VPNs. Time billing can be accommodated easily, and message unit billing practices might be adaptable to usage pricing as well, even that based in part on QoS. Nevertheless, it is clear that a more flexible system of "call detail recording" would be helpful, and that would involve making billing systems understand all of the new options.
When Will We See Them?The opening gambits in the VPNOSS wars are already underway, with Cisco and Ascend posturing the most impressively. Lucent and Nortel both appear to face some architecture changes if they are to fully realize the VPNOSS potential. While both companies certainly have the resources to make the changes theyd need, the time component of the picture isnt as favorable for them.
None of the software players, including those weve mentioned, has been able to gather the right combination of partners and press attention so far. In truth, its not clear whether any software firm is really going to try to field a full VPNOSS, or just court partnerships with an infrastructure vendor.
By about 2001, we expect VPN activity to be impressive enough to create major problems for service providers who dont have a proper foundation for the operations support process. That, ultimately, will set the forward limit on how far the market can stumble along without a good solution.
Theres always a chance for a surprise in this space. US West, at least, has taken the step of going to a software provider (Syndesis) for a "topology mapper" element that would create for the carrier the central model of provisioning we talked about earlier. With the carriers big wallets opening, a lot of action could take place in a hurry, even from players who have little or no established position in the market. Remember, Cascade jumped into frame relay prominence on the strength of the potential RBOC frame relay market alone, without any real wins to back them up. That shows that even a new player can become a giant when the market conditions are primewhich they may be.
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Strategies |
In a marketplace thats used to electrical multiplexing in forms ranging from TDM to ATM, optical networking seems like a real stretch. To make matters worse, the marketplace is full of hype (no surprise there, right?) about the possible scope of the optical opportunity.
Weve had optical networking for a decade or more. The new wave of optical interest, if theres any substance to it at all, has to present not just optical fiber utilization but some way of substituting optical processes for electrical processes within the infrastructure. If that happens, then the equipment balance can shift, and vendor opportunity with it.
Dense Wavelength Division Multiplexing is a topic weve explored in a "definition" sense in a prior issue. What were going to examine here is how the market for DWDM could develop, and where that might impact the rest of the network product and service market.
The Value of Traditional DWDM What DWDM does, for those who missed our last piece, is provide a means of multiplexing multiple optical carriers onto a single fiber by separating each in wavelength (lambda, as it is called). "Normal" WDM would provide a dozen or so lambda carriers per fiber, while DWDM could provide hundreds.Each lambda in a DWDM system can look to an electrical layer (SONET, for example) like a virtual fiber. This means that the capacity of the fiber is multiplied considerablyhundreds of times if there are hundreds of lambdas. It also means that there are now two ways of multiplexing traffic up to higher densityusing the SONET hierarchy or using DWDM. Each of these DWDM facts has its applications.
Higher capacity through DWDM can reduce the unit cost of transport in networks. The cost of a long-haul connection is in part the cost of laying the glass along the path. The more traffic the glass can be made to carry, the lower the unit cost of bandwidth to each user. This isnt saying that doubling the lambda count halves network cost; equipment, craft costs, and profits all figure into the total cost of service. Estimates of how much bandwidth cost makes up of total cost vary depending on application and the orientation of the estimator, and range from about 15% to about 45%. All that range is probably valid in some applications.
Some may think that the cost-reducing benefits of DWDM would be enough to justify it, but thats not the case. Carriers cant necessarily sell all the capacity that DWDM could create, and theres no incentive to invest in new technology to lower margins and profits. There are certainly carriers and situations where DWDM capacity augmentation makes senseon an undersea cable, for examplebut the "more-bits" argument isnt compelling market-wide at this point.
What may be compelling is the multiplexing issue. Today, most multiplexing in transport networks is done through SONET, a complex synchronized set of standards that provide for the creation of successively faster optical trunks by the combination of lower-speed ones. An OC-3 is roughly three DS3s, and four OC-3s make an OC-12then so forth up to OC-192 or better.
The problem with the SONET approach is in how it handles high-speed data traffic. A single 155 Mbps (OC-3-level) data trunk could be combined with three "telephony" OC-3s to create an OC-12. As the data needs expand, however, the introduction of a single data trunk is enough to move a SONET network up to the next OC-levelwhich doubles the capacity. All of the SONET add-drop multiplexers in each fiber nexus have to pass this mega-pipe through, since none can handle its data payloads directly. This adds cost and complexity to all the components of the network.
What DWDM does is let these fast data channels travel on their own lambdas, bypassing the SONET hierarchy of add-drop multiplexers. The introduction of a fast data trunk along a fiber route now has no impact on the SONET electronics already in placeit goes over another lambda with its own electronics to support it.
The reason this is important is the growth of data traffic. If we measure network traffic at the point of origination and convert everything to digital form, voice or circuit-mode traffic still makes up over 80% of the traffic in the network. Most of this, however, is local calling that never touches a backbone. On long-haul backbones, voice is only about 55% of traffic today, and that number is shrinking. The introduction of this kind of data volume in standard SONET terms would result in all manner of new high-level SONET ADMs, possibly displacing some of the current gear. With DWDM, the new data stuff goes onto its own lambdas and the other traffic and equipment is untouched. The most efficient way to add high-speed data traffic to a fiber network is DWDM.
DWDM In Non-Traditional Applications Most of the talk about DWDM has been focused on what might be called the transport space, or the use of DWDM on long-haul fiber. While the bit-savings benefit of DWDM is greatest where the cost of the fiber path end to end is highest, the multiplexing value of DWDM is also at least interesting even in shorter-haul applicationslike the outside plant network.Linking customers to a serving office is the mission of the outside plant. The makeup of this part of the local exchange network varies with the density of business users and the age of the infrastructure, but it is common to have a combination of fiber loops to business, fiber feeds to remote concentrators, and copper loop.
Introduction of high-speed access connections to anyone in this structure can mean impacting a lot of equipment in place, and that raises the costs. In addition, if the equipment in place is an incumbent LECs outside plant hardware and the serving carrier is a competitive player, any strategy that would impact the hardware may be flatly rejected, no matter what the service revenue stream might look like.
DWDM would allow new local access service to be provisioned over a lambda that didnt impact the incumbent equipment, customers, or services in any way. At the very least, this could drop the incremental cost of the new access connection considerably because it wouldnt require displacing capital equipment already installed. At most, it might enable a competitor to offer service where none could be provided otherwise.
Transparent LAN service is a good example. TLAN requires 10 Mbps connection in most cases, which is far above the level that would normally be supported on any outside plant multiplexing equipment. If a fiber strand ran right by the proposed TLAN site, it couldnt be used in traditional networking because the new service wouldnt be compatible with the electrical hardware associated with the service on that strand. With a lambda, that old service and the new TLAN are "ships passing in the night" and would have no effect on each other.
As great as this sounds, its not quite that easy. Most of the older optical gear isnt compatible with DWDM lambda divisionthe old stuff slops over all the lambdas and generally messes things up. Thus, it may be necessary to replace older optical gear to make fiber DWDM-compatible in the first place. If that first cost cant be justified, it may be hard to bootstrap DWDM in. This is particularly true in outside plant applications, because the financial benefits of DWDM are more limited in these applications owing to lower traffic density.
The Key to Multiplexed DWDM If multiplexing benefits are the primary drivers to DWDM both in transport and access applications, then it should be clear that transit switching at fiber nexus points is the key to multiplexing. Paths created over multiple fiber spans using DWDM have to be cross-connected between the fibers at the meet points. If this is done at the SONET/electrical level, the cost of the transit equipment is high enough to limit the value of DWDM overall. This, we believe, is why most DWDM value calculations show the threshold traffic level for economical operation to be OC-48.There are two ways of providing lower-cost cross-connect at the Lambda level, but both depend on the proposition that the entire DWDM payload is transiting the fiber nexus, meaning that nothing is being inserted there or removed for downstream delivery.
The first strategy is to devise a simple optical-electronic-optical connecting device that extracts the lambda from the fiber to an electronic format more readily handled, provides any necessary digital re-shaping, and then converts the result back to lambda form. This mechanism would also allow "lambda-hopping", or the conversion of lambda values incoming to outgoing to avoid collision of two payloads that want the same wavelength.
The second approach is to perform the cross-connect in the optical domain. This concept, an aspect of what is called "photonic switching", would eliminate the need to convert to the electrical domain completely. Some research centers believe commercial photonic coupling of this type will be available within three to five years, and it may even be possible to perform a lambda change with the conversion to help manage wavelengths more efficiently.
A similar problem exists for add-drop functions in DWDM. Today, the practice is to terminate all of the lambdas each time an insertion, drop, or cross-connect is required. This increases the ratio of equipment cost to fiber cost dramatically in applications where many such points can be expected, which would be the case for local access applications like transparent LAN.
Photonic processing of various types is clearly a key to the widespread deployment of DWDM, because this type of handling would reduce the equipment cost in a DWDM network. Without it, the tendency will be to focus DWDM on long-haul transport applications where the ratio of fiber cost to equipment cost is high anyway.
DWDM and Higher Layers Obviously, the introduction of DWDM as a formal multiplexing strategy would impact other technologies with similar missions. SONET, with a point-to-point electro-optical interface and an overlay multi-path network architecture, would certainly be impacted quickly. If DWDM were to be made cost-effective at OC-3 levels, for example, it would be doubtful whether SONET would be useful at all.The relationship of DWDM to higher-level protocols like ATM is harder to foresee. It is very unlikely that users will be provided with their own lambdas for network-building any time in the next two decades, in our view. The ratio of user capacity consumed to transport capacity deployed determines the value of multiplexing, at least in part. If users continue to operate at sub-DS3 rates for a decade or more (which we think is likely), there will be a need to concentrate multiple user flows to reach the threshold of DWDM economics. ATM could provide that concentration, creating an ATM electrical layer between telephone switch and IP service functions and the DWDM transport network. This would clearly squeeze SONET out, a point weve made in past articles.
Its pretty clear that this is at least part of Ciscos and Ascends vision of optical networking. What is not completely clear is exactly how it will all come about. The service provider industry is moving away from a regulated monopoly status to a competitive market. In such a market, investment must be linked to improved profits, and carriers have a long depreciation cycle on existing network technology. The best hope to introduce something new on a large scale is to link it to a new revenue source. Weve heard dozens of candidate sources in the past, including multimedia, but none have proved valuable enough to bring about major network change.
It is the revenue source, not the technology, that will catalyze DWDM.
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Down the Line |
In our next issue, were going to review the recent activity in the "SS7" space. Cisco has acquired Summa Four, a small switch vendor with a strong SS7 focus. Ascend now proposes to acquire Stratus, a major player in SS7 nodes and processors. Whats happening here? We will also be sending out our vendor questions on advanced ATM carrier switch products early in September, with an eye on publishing the first analysis in early December. Vendors note: We will be publishing reports in roughly the order we receive responses.
CIMI Corporations market report "IP VPNs and MPLS: Twin Keys to 21st-Century Public IP Success" will be available on August 19th. Interested parties should contact us for an executive summary and order form. Please note that this is a controlled distribution report, and you must qualify to receive it. Do not send money unless you have been advised that your order is approved.
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