Common use of Points of Presence Clause in Contracts

Points of Presence. needs. The DWDM network is used to provide native wavelength services to customers and is used to provide transport to the CenturyLink IP/MPLS and ATM networks. The SONET-over-DWDM network also provides trunking for the CenturyLink ATM network as well as the CenturyLink voice network and SONET-based private line services. The CenturyLink OC-192 SONET backbone network is designed with four- fiber Bi-directional Line Switched Ring (BLSR) architecture to provide excellent survivability and increase the transport network availability, specified on Bellcore GR-1230-CORE: SONET BLSR Equipment Generic Requirement. The four-fiber BLSR architecture provides excellent survivability (99.999%) against multiple concurrent faults since it supports both ring and span switching. Four-fiber BLSR span switching provides flexibility when performing routine maintenance activities. Though a multi- node BLSR system is more complex to design and maintain than a Unidirectional Path Switched Ring (UPSR) system, it has the advantage of maximizing bandwidth utilization and has a higher capacity. CenturyLink has concentrated Layer 2/3 core nodes in TeraPOPs across the country. All IP, ATM, and Frame Relay core switching is concentrated into these TeraPOPs. IP, ATM, and Frame Relay access equipment is located in these TeraPOPs and in other access POPs around the country. Concentrating core switching into TeraPOPs and using consistent platforms throughout helps us deliver a network that optimizes both cost and performance. The network is economical to deploy, manage and upgrade. Concentrated switching points also reduce the number of hops, which reduces latency in the network. The CenturyLink IP backbone currently operates at OC-192 (10 Gbps) speeds using point-to-point links between the IP Core routers. IP services are provided on industry leading equipment from Cisco Systems and Juniper Networks. The CenturyLink ATM and Frame Relay Network employs Lucent GX-550 and CBX-500 switches. The CenturyLink voice network consists of Nortel DMS 250 switches for domestic circuit switched traffic, DMS 300 switches for international circuit switched traffic and Sonus GSX switches for domestic packetized voice traffic. CenturyLink’s IP platform employs multiple complementary levels of protection to prevent node and switch failures. Protection begins at the switching component level with state-of-the art, low power technology. At the system level, protection options include full control and switching redundancy, power supply redundancy, interface redundancy and automatic path rerouting. All CenturyLink network routes have diverse, redundant fiber paths available for immediate restoration in the event of an outage. Nationwide IP/MPLS Network The IP network is given lambdas at each IP POP. These lambdas are then connected through the network to provide direct TeraPOP to TeraPOP connectivity. Note that this design eliminates the underlying SONET infrastructure inherent in earlier architectures. The router interfaces utilize POS (Packet over SONET) for the OSI Layer 1 protocol, but the SONET is strictly to provide line coding and timing functionality on point-to-point links. Without SONET protection in the network, the intelligence moved out of the transport network and into the IP network. This means the IP network was now responsible for its own recovery in case of a fiber cut or other failure. It Comply (Yes/No) Explanation/Description (2. Points of Presence) now relied on Layer 3 restoration instead of Layer 2. Using point-to-point wavelengths significantly simplified the transport network, while decreasing the cost and provisioning complexity of the transport part of the IP network. SONET equipment was not required on the ends to provide the ADM and APS functions. This reduced the overall cost per mile of lambda-based OC- 192s to less than half that required for IP over SONET. Using MPLS Fast Reroute, recovery times for network failure have actually been significantly improved over that provided by SONET Automatic Protection Switching. CenturyLink IQ Internet Port sets a new standard for Internet connectivity, with one of the most advanced networks available, best-in-class SLAs and some of the highest customer access speeds in the industry today. CenturyLink was the first NSP to offer an off-net SLA guaranteeing 95 ms between the top five networks. CenturyLink IQ Internet Port customers can utilize their connections to use e-mail, file transfers, and e-commerce applications to expand their reach and collapse physical boundaries. Mileage identifying the distance from the Internet POPs in Virginia to VITA locations is located in Attachment 6 to the proposal as an Excel file.