Troubleshooting guide

8-10
Cisco Broadband Local Integrated Services Solution Troubleshooting Guide
OL-5169-01
Chapter 8 Troubleshooting the Cisco Catalyst 6509
Troubleshooting Serial Lines
Gigabit/Fast Ethernet (GE/FE)
As bandwidth demands increase in the Internet, service providers must cost effectively scale their
networks and maintain network simplicity. Ethernet interfaces on the Cisc0 12000 Series help meet this
critical requirement. The Cisco 12000 Series offers both Fast and Gigabit Ethernet line cards in a variety
of port densities, including a high-density, 10-Port Gigabit Ethernet line card compatible with
10G-enabled Cisco 12400 Internet Routers.
Packet Over SONET/Synchronous Digital Hierarchy (POS/SDH)
POS enables Internet routers to send native IP packets directly over SONET/SDH frames. POS provides
lower packet overhead and lower cost per Mbit than any other data transport method. These efficiencies,
along with the increasing evolution of the optical network, enable POS to efficiently support increases
in IP traffic over existing and new fiber networks.
POS is a SONET/SDH compliant interface that supports SONET/SDH level alarm processing,
performance monitoring, synchronization, and protection switching (through APS/MSP). This support
enables Cisco 12000 Series Internet Routers to seamlessly interoperate with existing infrastructures
and/or migrate to packet-based optical networks, thus eliminating the need for expensive "forklift"
upgrades to existing equipment as demand for services escalates. In addition to backbone applications,
POS is often used for customer access and intra-pop connectivity. As the inventor of POS, Cisco offers
a range of Cisco 12000 Series POS line cards that can be interconnected over SONET/SDH
infrastructures, dark fiber connections or DWDM gear.
Dynamic Packet Transport (DPT)
DPT is a resilient packet ring (RPR) technology designed to deliver scalable Internet service, reliable
IP-aware optical transport, and simplified network operations. Principally for metropolitan area
applications, DPT-based solutions allow Service Providers to cost effectively scale and distribute their
Internet and IP services across a reliable optical packet ring infrastructure. DPT is based on Spatial
Reuse Protocol (SRP), a Cisco-developed MAC-layer protocol for ring-based packet internetworking.
Cisco has submitted SRP to the IEEE 802.17 Resilient Packet Ring (RPR) Working Group for
consideration as a standard.
DPT technology enables a set of carrier-class IP solutions, which leverage existing and emerging
technologies. These solutions include ISP internetworking, Regional Metro IP internetworking, and
Metro Internet Access.
Troubleshooting Serial Lines
This section describes methods for detecting and correcting data errors on the Cisco 10000’s serial
interfaces.
Optical Signal Input/Output Problems
Signal input and output problems can occur at any point in the network and can be caused by mechanical
defects in cables or fiber, poor connections, or loss of signal caused by other equipment failures.
Refer to your site log and other facility records to isolate signal connections for your facility.