Enterprise and business services clients represent an attractive and stable market for access network providers who can support their mission-critical voice, data, and TDM connectivity requirements. Fixed-line carriers are exploring access network options in order to competitively serve business-services customers while alternative carriers (e.g., CLECs, MSOs) eye the market as an opportunity to create differential advantage with new service bundles.
Voice communications may be carried over VoIP or TDM circuits that connect the PSTN to local PBXs. TDM applications have a variety of stringent ITU-T-defined performance requirements for MTIE, jitter, and wander, as well as other economic considerations. Broadcom-based EPON is the ideal transport network for TDM connectivity based on economics, performance, and application flexibility. High-performance Internet connectivity is also very important of course. Service providers must provide guaranteed service level agreements (SLAs), assuring clients that their traffic will be unaffected by other's and that quality of service metrics are maintained.
Service reliability is by far the most important criteria by which alternative providers are judged. Broadcom provides its system vendors customers with the foundation to achieve carrier-class service, including regression-tested firmware and other elements such as network monitoring functionality that enables carriers to anticipate problems and repair them before they become service affecting.
Subscriber demand for higher-speed access networks is growing and competitive pressures are upping the broadband ante - driving MSOs to develop new solutions that leverage their networks and subscriber base to create profitable and differentiated services. As a leading provider in IEEE 802.3 EPON chips for the deployment of triple-play services in broadband access networks, Broadcom has developed head-end and CPE System on Chip (SoC) products that specifically address MSO Business and Residential requirements.
Any new access platform must be able to support the existing MSO service-delivery architecture, while providing the required combination of cost competitiveness and back-office integration as well as meeting ever-increasing user expectations for throughput, QoS, and advanced video services. IEEE EPON solutions have the following advantages for residential and business/enterprise applications:
- EPON increases the bandwidth per customer by a factor of 10 or more, compared with traditional networks;
- EPON is the most cost-effective way to leverage existing fiber and expand the fiber network to new areas;
- EPON is the world's predominate FTTP technology deployed by incumbents, CLECs, and MSOs;
- EPON is an open IEEE standard (802.3ah), and its organization is open for anyone to join;
- EPON service flows map 1:1 with existing DOCSIS solutions, providing complementary services that can be managed through DOCSIS over EPON solutions.
With millions of triple-play residential and commercial subscribers deployed by more than 35 network operators and dozens of system vendors, Broadcom offers best-of-breed EPON SoC solutions for central office and customer premises equipment. Broadcom combines low-cost EPON connectivity with unique traffic management capabilities that inexpensively shape and manage services at the edge of the operator's network reducing capital and operation expenditures. Through the use of multiple "logical links" (LLIDs) per end-user device, Broadcom's EPON solutions support and manages Service Level Agreements (SLAs) on a per-service, per-customer basis, in much the same way DOCSIS systems operate today.
When evaluating and selecting a new technology it is important to ensure that there is a viable ecosystem of infrastructure, customer premises and test equipment, as well as optical components, to support commercial deployments. As a leading provider in EPON SoCs, Broadcom has developed an extensive community of system vendors, OEMs, ODMs, test equipment manufacturers and partners to ensure interoperability, performance, and secure supply of its advanced EPON solutions to network operators.
Equipment at service provider central offices (or cable MSO head ends) has two main functions: bandwidth distribution and allocation, and network management: control, provisioning, and maintenance. Scalable-performance and high-reliability are fundamental requirements, as are high-density/low-power to support thousands of subscribers.
Designed for access networks serving both business and residential subscribers, Broadcom' OLT chips provide all the built-in functionality and performance required for delivering triple-play services. For example, the Broadcom TK3723's Turbo-EPON® MAC features a configurable Dynamic Bandwidth Algorithm (DBA) that supports hierarchical fairness for guaranteed Service Level Agreement (SLA) contracts. Fully configurable L2/L3/L4 line rate packet processing allows for advanced classification, filtering, and application monitoring.
To meet the needs of subscribers and carrier business models, real-world triple-play networks face the challenge of continuously delivering an endlessly-varying combination of bursty MPEG-compressed video, latency-sensitive VoIP calls, and Internet traffic. High-capacity traffic management and shaping in the central office/head-end are required to satisfy these requirements - yet may add many thousands of dollars in capital expenditures. The TK3723 has more than 2,000 shapers and supports up to 512MB of packet buffering - enabling 2-5 seconds of buffering per IPTV channel, while grooming network traffic to optimize utilization while maintaining guaranteed service levels.
Driven by competitive pressures and market evolution to 3G and 4G, cellular service providers are seeking alternatives for economical and future-proof access network technologies. Much of the demand is driven by the need to provide higher bandwidth transport for mobile Internet connectivity.
A fundamental challenge facing both cellular and access network providers is predicting how and when the cellular market will evolve. Evolutionary requirements include:
- Increase in backhaul bandwidth: Data traffic in mobile networks is increasing dramatically as 3G rolls out and new subscriber services emerge. Some access network providers are splitting their IP and voice backhaul services into a hybrid of TDM and IP. Longer term it is expected that bandwidth and economics will drive these networks to converge to IP only;
- Synchronization clocks: Base stations must have closely-correlated carrier frequencies (and for TDD, phase) to support cell-to-cell handoff and for overall service quality. This requirement is currently satisfied via synchronization with TDM circuit clocks or local GPS receivers, which have high OpEx/CapEx and do not satisfy all cellular needs.
The table below provides a summary of some of the cellular service requirements and considerations:
Multi-dwelling and multi-tenant units present especially challenging requirements for access service providers including: maintenance of secure and stable communications between all subscribers, service isolation to prevent inter-service congestion, and provisioning and enforcement of service level agreements for sensitive traffic such as cellular backhaul (often found on rooftops). Additionally, it is often impractical to replace the building communication infrastructure.
Broadcom's EPON architecture provides the foundation technology required for reliable high-performance deployment to MDU/MTU buildings:
- TurboEPON® solution provides 2 Gbps downstream data rate to support more than 50 to 100 HDTV streams while leaving 1 Gbps for data traffic or enables high split ratios for reduced capital expenditures
- Field-proven hardware-based DBA guarantees SLA service contracts, maintains bandwidth-allocation fairness, and optimizes link utilization;
- ARP snooping, ARP proxy, and Precise ARP support provides faster response and prevents a variety of malicious user attacks;
- Multicast Group (MG) traffic management minimizes channel zap time and enhances image quality by minimizing packet loss, latency, and jitter;
- Comprehensive rule-based packet classification enhances network security, SLA enforcement, and supports billing applications;
- Over twenty VLAN modes allows flexible VLAN configuration, service to VLAN mapping, traffic classification into VLANs, and VLAN tag manipulation for service and management domain transition;
- China Interoperability Mode support (OAM extensions, triple-churning key encryption) is fully compatible with CTC requirements for China EPON deployment;
- IPv4 and IPv6 support provides compatibility with latest next-generation network deployments and service upgrades.
Single-family residence communications have a unifying thread: there is no "one size fits all" system or service model. Requirements vary dramatically between geographies, carriers, and subscribers. Services offerings may range from xDSL-upgrade to full HD-IPTV with bundled voice and high-speed Internet, and everything in between - representing an opportunity for access carriers to segment their markets with distinct value propositions.
