Houston Metro Ethernet Fiber

Layer 2 Communications offers Metro Ethernet Fiber solutions to address a wide range of Layer 2 networking needs, including point-to-point, point-to-multipoint, and any-to-any WAN connectivity.

Metro Ethernet Fiber from Layer 2 Communications provides clients with an additional option for transport that is less expensive and faster than the legacy network protocols.  Metro Ethernet Fiber is rapidly becoming the transport architecture of choice because of it is a superior platform for the convergence of Internet, data, voice, and video.  Metro Ethernet Fiber is ideal for backhaul of mobile voice, data, and multimedia traffic.  Layer 2 Communications deploys a core MPLS network that is redundant and carrier-grade, and also developed a “last-mile” tool kit that utilizes Ethernet over copper, Ethernet over NxT1 and NxDS3, and Ethernet over wireless technologies.  Layer 2 Communications Metro Ethernet Fiber product has the power to span metropolitan and regional footprints with highly scalable solutions, removing the bottleneck between the LAN and the WAN.

• Redundant MPLS routing over a self-healing DWDM fiber backbone
• Improved scalability from 1 Mbps to 10 Gbps for improved
• efficiencies
• More cost-effective and flexible WAN solutions than from older technologies
• Higher security control than public Internet solutions
• Flexible interfaces including 10/100Mbps FastE, 1000 Mbps GigE and 10 Gbps Ethernet
• Operations, administration, management and provisioning efficiencies
• Lower capital and operational expenditures compared to other data services
• Native Ethernet solutions for uncomplicated IP support and trouble-free network convergence
• Custom network configurations
• 24x7x365 world-class Network Operations Center (NOC)
• Superior customer support

Metro Ethernet Fiber’s success in the LAN environment has fueled the growing demand for a solution that can replace costly private line circuits and their associated equipment costs. Metro Ethernet Fiber’s simplicity coupled with bandwidth scalability, bandwidth granularity, and fast provisioning is driving rapid adoption of Metro Ethernet Fiber for business in the metro environment.

Unlike many Metro Ethernet Fiber carrier service providers that limit their offerings to central business districts and a select number of high-rise office buildings, Layer 2 Communications Metro Ethernet Fiber is available across a vast metropolitan area. In the Houston metro area alone, Layer 2 Communications has over 4,500 miles of existing Metro Ethernet Fiber enabled optical fiber cable and that network grows daily. From north of The Woodlands to Galveston Bay, and from east of Katy to beyond Baytown, Layer 2 Communications has the Houston metropolitan area covered. With so much fiber already in place, Layer 2 Communications can offer your business the scalable and cost-effective Point-to-Point and Point-to-Multipoint Metro Ethernet Fiber solutions that will put your business ahead of the competition.

Technology Overview of Metro Ethernet Fiber
Metro Ethernet Fiber has evolved to meet the increasing demands of packet-switched networks. With proven low implementation cost, its known reliability, and relative simplicity of installation and maintenance, its popularity has grown to the point that today nearly all traffic on the Internet originates or ends with a Metro Ethernet Fiber connection. Further, as the demand for ever-faster network speeds has grown, Metro Ethernet Fiber has been adapted to handle these higher. The One Gigabit Metro Ethernet Fiber standard is already being deployed in large numbers in both corporate and public data networks, and has begun to move Metro Ethernet Fiber from the realm of the local area network out to encompass the metro area network.

Meanwhile, an even faster Metro Ethernet Fiber standard is nearing completion. This latest standard is being driven not only by the increase in normal data traffic but also by the proliferation of new, bandwidth-intensive applications. The draft standard for 10 Gigabit Metro Ethernet Fiber is significantly different in some respects from earlier Metro Ethernet Fiber standards, primarily in that it will only function over optical fiber, and only operate in full-duplex mode, meaning that collision detection protocols are unnecessary. Metro Ethernet Fiber can now step up to 10 gigabits per second, however, it remains Metro Ethernet Fiber, including the packet format, and the current capabilities are easily transferable to the new draft standard.

In addition, 10 Gigabit Metro Ethernet Fiber does not obsolete current investments in network infrastructure. The task force heading the standards effort has taken steps to ensure that 10 Gigabit Metro Ethernet Fiber is interoperable with other networking technologies such as SONET.

Metro Ethernet Fiber’s expansion for use in metro area networks can now be expanded onto wide area networks in concert with both SONET and also end-to-end Metro Ethernet Fiber. With the current balance of network traffic today heavily favoring packet-switched data over voice, it is expected that the new 10 Gigabit Metro Ethernet Fiber standard will help to create a convergence between networks designed primarily for voice, and the new data centric networks.

Metro Ethernet Fiber in the Marketplace
The accelerating growth of worldwide network traffic is having service providers look to ever higher-speed network technologies in order to solve the bandwidth demand crunch. Administrators typically use Metro Ethernet Fiber as their backbone technology. Metro Ethernet Fiber meets several key criteria for efficient and effective high-speed networks:

• Easy, straightforward migration to higher performance levels without disruption,
• Lower cost of ownership vs. alternative technologies – (acquisition and support costs)
• Familiar management tools and common skills base
• Ability to support new applications and data types
• Flexibility in network design
• Multiple vendor sourcing and proven interoperability

Applications of Metro Ethernet Fiber
Users agree that Metro Ethernet Fiber is inexpensive, well understood, widely deployed and backwards compatible from Gigabit switched down to 10 Megabit shared. Packets can leave a server on a short-haul optic Gigabit Metro Ethernet Fiber port, move cross-country via a DWDM (dense wave division multiplexing) network, and find its way down to a PC all without any re-framing or protocol conversion. With 10 Gigabit backbones companies will have the capability to begin providing Gigabit Metro Ethernet Fiber service to workstations and, eventually, to the desktop in order to support applications such as streaming video, medical imaging, centralized applications, and high-end graphics. Metro Ethernet Fiber will also provide lower network latency due to the speed of the link and over-provisioning bandwidth to compensate for the nature of data in enterprise applications.

Metro Ethernet Fiber in Network Attached Storage and or Storage Area Network
Metro Ethernet Fiber will provide infrastructure for both network-attached storage (NAS) and storage area networks (SAN). Prior to the introduction of Metro Ethernet Fiber, some observers maintained that Metro Ethernet Fiber lacked sufficient horsepower to get the job done. Metro Ethernet Fiber, they said, just doesn’t have what it takes to move “dump truck loads worth of data.” Metro Ethernet Fiber offers equivalent data carrying capacity at similar latencies to many other storage networking technologies including 1 or 2 Gigabit Fiber Channel, Ultra160 or 320 SCSI, ATM OC-3, OC-12 & OC-192. There are numerous applications for Gigabit Metro Ethernet Fiber in storage networks today, which will seamlessly extend to Metro Ethernet Fiber as it becomes available. These include:

• Business continuance/disaster recovery
• Remote backup
• Storage on demand
• Streaming media

At the End of the Day
As the Internet transforms longstanding business models and global economies, Metro Ethernet Fiber has withstood the test of time to become the most widely adopted networking technology in the world. Much of the world’s data transfer begins and ends with a Metro Ethernet Fiber connection. Metro Ethernet Fiber favaorable interest is caused by robust end user demand for E-Commerce and the demand for low cost IP services. Clients are looking for higher capacity solutions that simplify and reduce the total cost of network connectivity, thus permitting profitable service differentiation, while maintaining very high levels of reliability. Metro Ethernet Fiber is no longer designed only for the LAN. Metro Ethernet Fiber is the natural evolution of the well-established IEEE 802.3 standard in speed and distance. It extends Metro Ethernet Fiber’s proven value set and economics to metropolitan and wide area networks by providing:

•Potentially lowest total cost of ownership
•Straight forward migration to higher performance levels
•Proven installed base interoperability (Plug and Play)
•Familiar network management feature set

Enabling Profitable Metro Ethernet Fiber Services: The Next Step in Metro Networking

Many service providers are turning to Metro Ethernet Fiber to meet the growing demand for high bandwidth access to virtual private network and Internet services and to take advantage of the growth opportunities the Metropolitan (Metro) Ethernet Fiber market presents. They require a network architecture that can offer resiliency, scalability, service delivery, performance and long-term investment protection. This compares the existing bridging model used to enable many of today’s Metro Ethernet Fiber services with multiprotocol label switching (MPLS), the leading candidate for large-scale Metro Ethernet Fiber network deployment, to help service providers make the appropriate technology choice for their next generation Metro Ethernet Fiber network.

1 Today’s Metro Ethernet Fiber Networks
The Metropolitan (Metro) Ethernet Fiber market presents a significant growth opportunity for service providers. Service providers around the world are looking to Metro Ethernet Fiber to meet the growing demand for high bandwidth, granular access to virtual private network (VPN) services and Internet services. The future growth outlook of Metro Ethernet Fiber services has prompted service providers to evaluate and invest in new network infrastructure. This is true for incumbent service providers as well as competitive operators. With continuous technology advances and ongoing standards development, Metro Ethernet Fiber technology is now being deployed in Metro areas. Although Metro Ethernet Fiber services from early adopters have succeeded in gaining some market penetration, the use of bridging technology has significantly limited the size of the addressable market. For Metro Ethernet Fiber services to gain full market acceptance, service providers need to take the next step by building a robust and reliable service-oriented infrastructure based on scalable technologies. As service providers launch new Metro Ethernet Fiber service suites or expand existing Metro Ethernet Fiber services, they require scalable solutions capable of delivering service level agreement (SLA)-based services across a city or around the world, built with network elements engineered to carrier standards that include sophisticated service-oriented diagnostic and troubleshooting tools. Service providers must be cognizant of key adoption issues such as positioning Metro Ethernet Fiber services into the existing service mix, the impact Metro Ethernet Fiber services will have on current revenue streams, the market perception of Metro Ethernet Fiber not being ready for mission critical business applications and Metro Ethernet Fiber’s glaring omission of absolute quality of service (QoS) mechanisms. This compares the existing bridging model used to enable many of today’s Metro Ethernet Fiber services with multiprotocol label switching (MPLS), the leading candidate for large scale Metro Ethernet Fiber network deployment. The intent is to discuss these technology choices to help service providers make the appropriate technology choice for their next generation Metro Ethernet Fiber network.

2 Metro Ethernet Fiber Service Creation
Compelling revenue opportunities in the Metro Ethernet Fiber services market have led service providers to look for innovative ways to meet the double-digit growth in demand for Metro Ethernet Fiber services. These plans are being considered in conjunction with the ongoing work of convergence to a single network technology and architecture. Since their inception in the mid 1990s, Metro Ethernet Fiber services have matured into data connectivity services with applications limited to transport, local area network (LAN) interconnect and, more recently, Internet access. As service providers work hard to avoid being trapped with yet another commodity connectivity business, they are keenly interested in deploying value-added Metro Ethernet Fiber services to ensure long term profitability of their Metro Ethernet Fiber network investments. These value-added services include VPNs, video and storage applications. These new services will require a network architecture that has the advanced traffic management and diagnostic capabilities to enable differentiated services and enforce demanding SLAs. The technology choices a service provider makes today must ensure end-to-end service delivery for current and future services. The delivery of value-added services encompasses such network attributes as resiliency, scalability, service delivery and multiservice convergence. MPLS offers the differentiated service capabilities to provide value-added services.
“MPLS will be the clear winner for VPN creation and consolidation of networking infrastructure.” AT&T “MPLS and Metro Ethernet Fiber will become more strongly linked in the strategic plans of carrier data network providers.” PROBE, SEPTEMBER 2003 “Adoption issues that may slow rollouts of Metro Ethernet Fiber services include the limited scalability and lack of QoS mechanisms of legacy Metro Ethernet Fiber platforms,…” PROBE, SEPTEMBER 2003

2.1 Service Resiliency
Network resiliency is a critical factor in delivering reliable services. Today, Metro Ethernet Fiber is primarily used for basic best-effort Internet access. As service providers expand their range of higher value Metro Ethernet Fiber connectivity services for business customers, including SLAs, network availability becomes a significant contributor to revenue and profit. Service guarantees in the form of SLAs require a resilient network that instantaneously detects facility or node failures and restores network operation immediately to meet the terms of the SLA. High availability is difficult to achieve within a Metro Ethernet Fiber network using traditional bridging. Bridging uses spanning tree protocol (STP), defined under IEEE 802.1d, to prevent loops and recover from link and port failures. However, the slow convergence time of STP makes bridging inadequate to support guaranteed services. Depending on the network topology, STP could take from 30 seconds to a few minutes to recover from a failure. Although protocol extensions, such as rapid spanning tree protocol (RSTP), defined under IEEE 802.1w, and multiple spanning tree protocol (MSTP), defined under IEEE 802.1s, have significantly improved convergence times, more complex meshed topologies will result in failover times in the order of a few seconds. Clearly spanning tree performance issues limit the array of resilient services that can be offered, impacting the potential profit for service providers. This coupled with the complexity of configuring and managing STP per customer, makes spanning tree an unworkable solution in the Metro core. In contrast to traditional bridging, an MPLS-based infrastructure can deliver the required availability to ensure guaranteed services. Through mechanisms such as dedicated backup label switched paths (LSPs) and fast reroute, the Metro Ethernet Fiber network can provide the sub-50-millisecond failover times needed to maintain end user transparency, even when thousands of services are simultaneously affected by a failure. Between the service provider’s edge switch and the customer’s switch or router, STP can be supported, ensuring seamless connectivity for the customer and full compatibility with their existing network. Service providers rely on resilient networks to meet stringent SLA obligations and reduce customer churn. MPLS-enabled Metro Ethernet Fiber networks are designed to meet recovery requirements for guaranteed services up to 100 times faster than bridged networks.
“MPLS also allows service providers to leverage the resiliency and traffic engineering characteristics of MPLS, which some believe is a shortcoming of the spanning tree protocols.” RHK, MAY 2003

2.2 Service Scalability
To minimize capital expenditures and drive down operational costs, service providers require network architectures that enable services to scale effectively as the customer base grows. Scalable services require the separation of traffic from different users and no limits on the number or location of customers connected to the network. Bridging technology imposes a number of restrictions on the delivery of Metro Ethernet Fiber services. The use of virtual local area network (VLAN) tagging to separate and forward traffic, as defined under IEEE 802.1q, has an upper limit of 4,094 tags. With stacked VLANs, service providers can allocate one tag per customer and support up to 4,094 customers connected to the network while maintaining service transparency and separation. Stacked VLAN implementations are still proprietary and there are no interoperability standards that define how stacked VLANs should be implemented. The use of stacked VLANs increases capital costs by forcing service providers out of a vendor-competitive environment into a single vendor solution. Furthermore, the use of stacked VLANs needs to be consistent across the entire Metro, with unique tags for each customer. This forces service providers to manage the VLAN tags and reserve tag values at every network element in the network to prevent potential conflict and incorrect forwarding of customer packets. VLAN tag consistency makes it practically impossible to scale a bridged network across the wide area for inter-Metro services. A bridged network simply cannot scale to meet today’s service requirements. Conversely, an MPLS-based Metro Ethernet Fiber network has excellent scalability and interoperability attributes. With standards-based MPLS encapsulation and label switching, VLAN tags have only local significance. By mapping VLAN tags to LSPs, traffic can be efficiently separated and transparently carried over the network. MPLS can support tens of thousands of customers with no management overhead of VLAN tags. With MPLS, there is no geographical limitation in extending point-to-point or multipoint services across the wide area, since either MPLS or IP tunneling can be used. This allows service providers to expand their service reach to meet the needs of all customers, regardless of topology. The IETF has spent three years defining standards that enable MPLS to effectively deliver scalable Metro Ethernet Fiber services, with a high degree of interoperability. The MPLS model for Metro Ethernet Fiber services is based on well established and widely adopted drafts such as draft-Martini encapsulations for point to- point services (now known as draft-ietf-pwe3-ethernet Fiber-encap) and draft-lasserre-vkompella (now known as draft-l2vpn-vplsldp) for multipoint services. Both these drafts have achieved IETF working group status and are expected to become full requests for comment (RFC) in 2004. The crucial need for MPLS has been recognized by ITU, which has been working on it since 1999 and is currently making rapid progress. Several rounds of interoperability testing for Metro Ethernet Fiber services based on these drafts have been carried out between leading vendors since early 2003 with excellent results. Many leading service providers have now completed trials based on implementation of these draft standards, with some commercial services already available (e.g., Masergy’s in CONTROL VPLS). Service providers must have scalable services to minimize capital and operational costs. MPLS removes the 4,095 customer limit imposed by bridging with intelligent tunneling and switching technologies and flexible frame encapsulation. The MPLS approach puts no limit on the location of customers to allow for seamless integration of intra-Metro and inter Metro services. MPLS vendor interoperability has been widely demonstrated in both lab evaluations and commercial service provider networks worldwide.

2.3 Service Delivery
To expand the addressable market and increase profits, service providers are looking to move up the value chain through lucrative value-added services. For this service migration to take place, service providers require a network infrastructure with the advanced traffic management capabilities required to enforce the QoS parameters of customer SLAs. To support value-added services with guarantees on throughput and delay, advanced QoS mechanisms are needed. A Metro Ethernet Fiber network implemented using bridging is connectionless and does not offer any capability to reserve bandwidth for guaranteed services or to avoid congestion. Bridging offers only relative priority queuing, as defined under IEEE 802.1p. An MPLS-based infrastructure, however, has the traffic engineering features to support enhanced services such as mission critical business applications. Service providers can increase profitability with an assortment of higher margin differentiated services. MPLS has the inherent ability to set up pre-defined paths based on the service definition, apply application-aware policy to traffic flows and enforce SLAs. MPLS can also optimize network usage through load sharing by switching paths around bottlenecks to less congested links. This functionality cannot be implemented in a bridged Metro Ethernet Fiber network. The absence of hard QoS guarantees with bridging limits the scope and flexibility of available services. The robust QoS mechanisms of MPLS allow service providers to enforce the profitable SLA-based services they are keen to offer. The traffic management capabilities of MPLS minimize capital expenses by making efficient use of network resources and help to avoid unnecessary additional investments.
“MPLS will play a key role in both the aggregation of different traffic types using Metro Ethernet Fiber transport as well as in providing a mechanism for traffic prioritization and quality of service (QoS) guarantees.” PROBE, SEPTEMBER 2003 “MPLS technology ensures flexibility, scalability at an affordable price.” TELEFONICA DE ESPANA, BUSINESS-DRIVEN MPLS NETWORKS CONFERENCE, NICE, APRIL 2, 2003

2.4 Multiservice Convergence
As operational and capital savings continue to drive convergence across all network segments, it is imperative that service providers view Metro Ethernet Fiber deployments in conjunction with other infrastructure strategies. The emergence of IP/MPLS as the preferred choice for convergence has led service providers to invest in wide area network (WAN) backbone build outs. With IP/MPLS as the technology in the network core, there are many advantages to be gained by viewing the Metro Ethernet Fiber access network as part of the end-to-end network. MPLS facilitates the service goal of providing seamless connectivity and service assurance end-to-end. For service providers with, or moving to, an IP/MPLS core, the only requirement is the extension of MPLS from the backbone into the Metro. Today’s enterprise customers require flexible Metro Ethernet Fiber services that can easily span across the Metro or between Metros. With an MPLS-based model, services can easily scale geographically across Metro, national and international boundaries. In this way, MPLS promotes customer retention by giving the service provider the ability to adapt to changing enterprise topologies and the opportunity to expand into new service segments. MPLS also has the ability to interwork other Layer 2 protocols such as frame relay, onto an IP/MPLS backbone. With MPLS as the underlying access protocol, service providers have the option, depending on customer demand, to maintain existing frame relay services, interwork Metro Ethernet Fiber interfaces with frame relay interfaces or deliver Metro Ethernet Fiber interfaces to the customer. As customers migrate from frame relay to Metro Ethernet Fiber, service interworking gives service providers new revenue opportunities. It minimizes capital costs by allowing the continued use of deployed equipment and it leverages the existing infrastructure to improve margins for new services. Interworking is also a valuable tool to minimize potential revenue cannibalization concerns as Metro Ethernet Fiber services are added to the service portfolio. Another MPLS benefit is the full suite of diagnostic tools used to troubleshoot network faults. Without root-cause functionality, the human resource costs associated with troubleshooting network faults can be significant. The IETF has defined the operations, administration and maintenance (OAM) requirements for multi-vendor MPLS networks under draft-ietf-mplsoam- requirements. The ITU has also been working on MPLS OAM in Y.1711 as a further recognition of the need for MPLS in transport networks. The ability to rapidly diagnose outages in a multi-vendor environment represents considerable operational savings and helps promote customer loyalty. The use of MPLS as the Metro networking technology gives service providers the ability to deliver a seamless end-to-end service independent of geography, create flexible migration paths, manage current revenue streams, and provide extensive OAM diagnostic capabilities resulting in new revenue opportunities and substantial operational and capital savings.

3 Metro Ethernet Fiber Design Recommendations
To ensure long term profitability, service providers are poised to maximize revenue from the addressable market with value added Metro Ethernet Fiber services. These new services require a network architecture that can offer resiliency, scalability, service delivery and performance as well as long term investment protection. For many service providers, the technology choice must allow for the future integration and interworking of Metro Ethernet Fiber services with legacy services. Regardless of the size of the network, provisioning, operational complexity and capability must be considered. “Using MPLS also enables an enterprise to deploy Metro Ethernet Fiber at some locations, maintain FR and ATM at other locations and still have a VPN whereby all locations appear to be on the same LAN.” RHK, MAY 2003 Although native Metro Ethernet Fiber and bridging appear to provide a simple “plug-and-play” Metro Ethernet Fiber solution, on closer examination it is clear that the lack of carrier-grade levels of resiliency, scaling and OAM tools places severe constraints on both the size of the service footprint and the efficiency of network and service operations. MPLS is the superior networking technology to support the rigorous demands of next generation Metro Ethernet Fiber services. An MPLS-based Metro Ethernet Fiber network addresses all the service provider’s needs in the areas of resiliency, scalability, interoperability and service delivery. MPLS has the advanced traffic management and diagnostic capabilities to enable enhanced services and enforce demanding service level agreements.
“MPLS is to be treated as the target. It will give us the ability to provide all the things at Layer 3 or at Layer 2, and do it all on a common infrastructure.” VERIZON