Cisco Systems OL-16447-01 manual UNIs, NNIs, and ENIs, Dual-Purpose Port LEDs, page

Chapter 1 Product Overview

Front Panel

See the “Inserting and Removing the SFP Module Patch Cable” section on page 2-21for more information about using the SFP module patch cable.

You can order the SFP module patch cable (part number CAB-SFP-50CM=).

UNIs, NNIs, and ENIs

The switch supports user-network interfaces (UNIs), network node interfaces (NNIs), and enhanced network interfaces (ENIs). UNIs are typically connected to a host, such as customer premises equipment (CPE) or a home access gateway. NNIs are typically connected to a router or to another switch. ENIs have the same functionality as UNIs, but can be configured to support protocol control packets for Cisco Discovery Protocol (CDP), Spanning-Tree Protocol (STP), Link Layer Discovery Protocol (LLDP), EtherChannel Link Aggregation Control Protocol (LACP), or Port Aggregation Protocol (PAgP). Every port is in an UNI, ENI, or NNI mode at any time, but not all ports have to all be set the same.

By default, the dual-purpose ports on the Cisco ME 3400E-12CS-M and on the

Cisco ME 3400EG-2CS-A are configured as UNIs, and the SFP-only uplink ports are configured as NNIs. You must specifically configure ports to be ENIs; no ports are ENIs by default. By default, the 10/100 ports on the Cisco ME 3400E-24TS-M are UNIs, and the dual-purpose ports are NNIs.

A port can be reconfigured from UNI to NNI or an ENI, and the reverse. When a port is reconfigured as another interface type, it inherits all the characteristics of that interface type. For information on configuring interfaces, see the switch software configuration guide.

LEDs

You can use the switch system and port LEDs to monitor switch activity and performance.

•Switch LED Panels, page 1-8

•Power-Supply Module LEDs, page 1-9

•Ethernet Management Port LED, page 1-10

•Alarm LEDs, page 1-11

•Port LEDs, page 1-11

•Dual-Purpose Port LEDs, page 1-11

Cisco ME 3400E Ethernet Access Switch Hardware Installation Guide

OL-16447-01 1-7